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Review on Nanofluids: Preparation, Properties, Stability, and

Thermal Performance Augmentation in Heat Transfer Applications
Md Atiqur Rahman, S. M. Mozammil Hasnain,* Shatrudhan Pandey,* Anipa Tapalova,*
Nurgali Akylbekov, and Rustem Zairov

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ABSTRACT: Nanoparticles play a crucial role in enhancing the

thermal and rheological properties of nanofluids, making them a
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valuable option for increasing the efficiency of heat exchangers.

This research explores how nanoparticle characteristics, such as
concentration, size, and shape, impact the properties of nanofluids.
Nanofluids’ thermophysical properties and flow characteristics are
essential in determining heat transfer efficiency and pressure loss.
Nanoparticles with high thermal conductivity, such as metallic
oxides like MgO, TiO2, and ZnO, can significantly improve the
heat transfer efficiency by around 30% compared to the base fluid.
The stability of nanofluids plays a crucial role in their usability.
Various methods, such as adding surfactants, using ultrasonic mixing, and controlling pH, have been employed to enhance the
stability of nanofluids. The desired thermophysical properties can be achieved by utilizing nanofluids to enhance the system’s heat
transfer efficiency. Modifying the size and shape of nanoparticles also considerably improves thermal conductivity, affecting
nanofluid viscosity and density. Equations for determining heat transfer rate and pressure drop in a double-pipe heat exchanger are
discussed in this review, emphasizing the significance of nanofluid thermal conductivity in influencing heat transfer efficiency and
nanofluid viscosity in impacting pressure loss. This Review identifies a trend indicating that increasing nanoparticle volume
concentration can enhance heat transfer efficiency to a certain extent. However, surpassing the optimal concentration can reduce
Brownian motions due to higher viscosity and density. This Review offers a viable solution for enhancing the thermal performance of
heat transfer equipment and serves as a fundamental resource for applying nanofluids in heat transfer applications.

1. INTRODUCTION Industries like chemicals, food, oil, and gas utilize double-
The revolutionary impact of nanotechnology, with its pipe HX for various purposes like pasteurization, sterilization,
distinctiveness compared to conventional scales, has garnered reheating, preheating, digester heating, and effluent heating.
significant attention. This exponential growth has been fueled These heat exchangers are also common in renewable energy
by its diverse applications across various sectors, such as systems like solar energy, waste heat recovery, geothermal,
medicine, agriculture, engineering, and industry.1−5 As a combustion, latent heat energy storage, and air conditioning.
scientific discipline, nanotechnology delves into the properties The advantage of double-pipe HX lies in their modest design
of materials at the nanoscale. and ease of maintenance. They are typically compact in size
Nanotechnology facilitates the manipulation of materials at and can be easily installed in various locations. Additionally,
the nanolevel, where particles are one billionth of a meter or double-pipe HX are cost-effective and have a high thermal
10−9 meters. For instance, materials like alumina and titanium efficiency, making them an attractive option for many
oxide, with relatively high thermal conductivity, can be industrial applications. One of the key benefits of double-
engineered into small nanosized particles. These nanosized pipe heat exchangers is their versatility. They can be used for
particles are integrated into base fluids for heat transfer, both liquid-to-liquid and gas-to-liquid HX processes, making
forming a stable colloidal solution. When added to base fluids
with low thermal conductivity, they can enhance the fluids’ Received: April 5, 2024
heat transfer characteristics. This innovative concoction, Revised: June 19, 2024
known as nanofluid, represents one of the recent advancements Accepted: June 25, 2024
in nanotechnology. Notably, nanofluid introduces new heat Published: July 15, 2024
transfer characteristics, contributing to energy conservation
akin to downsizing heat transfer equipment.6
© 2024 The Authors. Published by
American Chemical Society https://doi.org/10.1021/acsomega.4c03279
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them appropriate for various applications. Also, double-pipe knowledge in the field. This review primarily focuses on
HX can handle various temperatures and Δp conditions, improving hm, Nu, HT rates, TPF, and other related
making them suitable for use in demanding industrial enhancements that can be impacted by using nanofluid. By
environments. suggesting new avenues for exploration, this review aims to
Thermal energy management relies heavily on the use of promote further research that can significantly contribute to
HX. In reply to the energy crunch, there is a growing demand the field of HT augmentation. Ultimately, this research may
for efficient HX to support the growth of energy-saving serve as a valuable resource for researchers seeking to
technologies in various industries. Researchers are concentrat- understand and enhance HT using nanofluids.
ing on enhancing equipment design and the thermal Below are essential points elucidated in this review article.
characteristics of working fluids to attain optimal energy Categorization of nanofluids.
efficiency. This focus on energy optimization is crucial as • Recent advancements in engineering thermal application
conventional fuel sources have limitations. Improving the owing to innovative HT mediums (nanofluid).
performance of HX can lead to significant energy savings. • Several significant parameters need to be considered
Numerous forms of HX, like plate-type HX, double-pipe HX, while selecting and preparing nanofluids.
HP, and mini-channel/heat sinks, offer compactness, effective- • Impact of integrating passive methods on HT and Δp
ness, flexibility, and high thermal performance. Plate-type HX efficiency of heat transfer applications.
was initially designed to meet the needs of dairy industries and
• Elaboration of significant factors that play a vital part in
has since found numerous applications in engineering sectors,
enhancing heat transfer characteristics of nanofluid.
including heat recovery, HVAC, cooling, power generation,
and refrigeration. Double-pipe HX is commonly used in power • Different models are used for calculating the thermody-
plants for electricity generation, with heaters and economizers namic properties of nanofluid.
being key components.7 The simplicity, ease of cleaning, and
low cost of double-pipe HX have made them popular in 2. NANOFLUIDS: FUNDAMENTALS, SYNTHESIS,
various applications.8 Portable devices like laptops and mobile STABILITY, AND PROPERTIES
phones require efficient cooling solutions, which has led to the Nanoparticles within nanofluids are minute solid particles
development of mini/micro channels and HP. While improved dispersed throughout the base fluid, exhibiting a specific
HT in HX leads to greater efficiency, it also increases pumping motion. They function as heat carriers, directly conveying
power requirements, necessitating a balance between enhanced energy.10 Additionally, they can be likened to “stirrers,″
HT and associated Δp.9 The primary issue concerning generating microconvection currents that augment the effective
nanoliquids is the substance used for the solid particles. A thermal conductivity of the base fluid. This enhancement
wide range of metals, metal oxides, and carbon-based materials primarily stems from the heightened motion of molecules,
are accessible, all of which are suitable options for improving consequently increasing their collision frequency and facilitat-
HT and have good mechanical properties. The main emphasis ing greater heat transfer through conduction. In contrast to
is finding the most effective material with minimal drawbacks microsized particles, nearly 20% of the total atoms within a
compared to other options while still performing well in all key nanoparticle (with sizes <20 nm) reside on the surface,
areas. It may seem logical to prioritize materials with high enabling efficient absorption and heat transfer. Conversely,
thermal conductivity, like silver or copper, to set a standard for microsized particles predominantly harbor their atoms beneath
other nanoliquid materials. However, this is not always the the surface, limiting their involvement in heat transfer
case. In addition to thermal properties, the long-term stability processes.
of the nanoliquid is crucial. As an outcome, extensive research Several hypotheses encompassing the principles of heat
has been shown to address stability issues, including various conduction in nanofluids offer insights that could aid in
chemical and physical treatments to maintain stability. understanding and verifying mechanisms for enhancing
The most recent research reviews the capabilities of thermal conductivity. These include nanoparticle Brownian
nanoliquid employed in HX with extended surfaces. Since motion, nanoparticle aggregation, the formation of a liquid
these techniques are rarely used together, limited information nanolayer surrounding nanoparticles, ballistic transport and
is available on this dual approach. The novelty of this research nonlocal effects, thermophoresis, and near-field radiation (see
lies in the lack of comprehensive evidence or reviews Figure 1). Although all these mechanisms have the potential to
discussing the use of nanofluid with extended surfaces. This explain the increase in thermal conductivity, there is a
paper delves deeper into this concept by examining the considerable likelihood that they may not apply uniformly
effectiveness and characteristics of various kinds of fins and across all nanofluid systems. This is primarily due to the
nanofluid particles found in existing literature, consolidating diverse behavior exhibited by a wide range of nanomaterials
this information into a single paper. This review aims to be a when interacting with different base fluids.11
cutting-edge assessment of the combined use of nanofluid and 2.1. Selection of Nanoparticles Based on the Base
extended surfaces in enhancing heat transfer, highlighting key Fluid. The primary determinant of nanofluid thermal
differences in studies, applications, and working conditions. conductivity lies in the foundational fluid, which constitutes
This comprehensive understanding of the impact of key the predominant portion of its composition. While nano-
parameters is crucial for improving heat transfer. In contrast to particles contribute to improving thermal conductivity, the
other reviews focused on specific applications, this review foundational fluid exerts the greatest influence. Thus, selecting
explores a variety of applications for both methods, such as the foundational fluid is equally crucial to choosing nano-
solar collectors, car radiators, and nuclear fuel rods, to particles. A diverse array of foundational fluids suitable for
emphasize the effects of critical parameters like particle deployment includes water, ethylene glycol, natural and
concentration and flow patterns on thermal performance. synthetic oils, ionic liquids, and refrigerants. Nanofluids
Therefore, it is essential to conduct this review to advance formulated with foundational fluids possessing high thermal
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acknowledge that the use of nanoparticle-infused fluids can

alter the liquid’s physical properties, increasing density and
viscosity in an unfavorable manner.21 This can lead to the
formation of nanoparticle clusters that may block flow
channels during turbulent movements. Additionally, due to
the potential instability of nanoparticle-infused fluids, using
high concentrations of the main liquids is not advisible.
Therefore, maintaining stability and nanoparticle concentra-
tion in these fluids is crucial and is an area of ongoing research
to develop reliable products for industrial use.
Different types of nanofluids are categorized into three key
categories based on the materials present. The first category,
Group A, consists of mononanofluids containing only one type
of nanoparticle, such as metals like Al, metal oxides like Al2O3,
or carbon-based nanoparticles like GNPs. A few of them are
Figure 1. HT mechanisms of nanofluids. Reproduced with the shown in Table 1.
permission of Bhanvase and Barai.10 Copyright 2021 Elsevier Inc.
Table 1. kp of Group A Nanoparticles and Base Fluids
conductivity exhibit superior thermal conductivity compared to
those formulated with lower thermal conductivity. Despite material thermal conductivity (W/mK) ref
ethylene glycol’s thermal conductivity being three times silver 424 22
inferior to water’s, it demonstrates a greater enhancement in aluminum 273 22
thermal conductivity. An endeavor to elucidate this phenom- iron 80 22
enon relates to the dispersibility of nanoparticles in different copper 398 22
foundational fluids illustrated in Figure 2; nanofluids steel 46 23
Al2O3 40 24
TiO2 8.37 25
CuO 77 26
ZnO 29 27
SiO2 1.2 28
diamond 3300 29
graphite 2000 30
CNT 2000 31
water 0.608 32
ethylene glycol 0.257 22
40:60% EG/W 0.404 33

The second category, Group B, includes nanofluids

combining two or more different solid nanoparticles.34,35
Lastly, Group C comprises hybrid nanofluids comprising
polymeric, metallic, or nonmetallic materials with significant
differences in solids or phase change materials.36,37 Various
Figure 2. Thermal conductivity of CuO nanofluid (5 wt %) as a efficient techniques must be employed for their preparation to
function of temperature using water, ethanol, and ethylene glycol as ensure the stability of nanofluids and minimize sedimentation
base fluids. Reproduced with the permission of Dehkordi and and changes in chemical composition. These techniques may
Abdollahi.12 Copyright 2018 Elsevier Ltd. involve adjusting the pH of the suspension, using surfactants as
dispersants, or employing ultrasonic vibration.38 The main
containing identical nanoparticles display varying rates of objective of implementing these methods is to modify the
thermal conductivity ratio augmentation with temperature surface physiognomies of nanoparticles, enhance their
elevation owing to differences in foundational fluids.12 dispersibility within the base fluid, and avert particle
Nanoparticle-infused fluids are seen as an innovative agglomeration.39 Equations 1−4 describe the governing
solution for enhancing HT in various engineering settings, equations linking nanofluids’ hydraulic and thermophysical
offering a versatile and effective approach. Due to their small properties and base fluids based on nanoparticle vf. Equations 5
size, they can be utilized in microscale devices, showing to (9) are essential HT equations used for data analysis to
promise in industries such as automotive,13,14 HVAC, and study the THP. A few of Group C are shown in Table 2.
electronics.15 This technology could be used as a unique form knanoparticle + 2k base fluid + 2 (knanoparticle k base fluid)
of coolant for cars, leading to better thermal performance and knano = k base fluid
knanoparticle + 2k base fluid (k nanoparticle k base fluid)
benefits like improved fuel efficiency, reduced pollution, and
(1)
enhanced engine performance.16 They could also improve 40
coolants in small-scale environments with limited cooling
space.17 Recently, adding nanoparticles to PCM has reduced = (1 + )
nanofluid base fluid (2)
melting time, resulting in nanoparticle-enhanced PCM for
better thermal energy storage.18−20 However, it is essential to 41

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Table 2. Few Group C Nanofluids

investigators nanoparticles base liquid
Suresh et al.44 Al2O3−Cu H2O
Esfe et al.45 MWCNT−ZnO oil
Esfe et al.46 Cu−TiO2 H2O/EG
Abbasi et al.47 Al2O3/MWCNT H2O
Afrand48 fMWCNT−MgO EG
Gürbüz et al.49 CuO−Al2O3 H2O
Ahammed50 Al2O3−graphene H2O
Chen et al.51 Fe2O3/MWCNT H2O
Esfe et al.52 Ag−MgO H2O Figure 3. Single-step method. Reprinted with the permission of Kong
Chopkar et al.53 Al2Cu/Ag2Al H2O/EG et al.76 Copyright 2017 from from the Royal Society of Chemistry.
Martin et al.54 Fe−CuO H2O
Minea55 SiO2/TiO2/Al2O3 H2O approach simplifies the conversion of nanoparticles into liquid
Asadi and Asadi56 MWCNT−ZnO oil form without requiring multiple preparatory steps.77 High-
Gürbüz et al.57 ZnO−Al2O3 ammonia/water lighted as a benefit, the single-step method eradicates the need
Nine et al.58 Cu−CuO2 H2O for drying, storing, transporting, dispersing, and oxidizing,
Jana et al.59 CNT−Au H2O resulting in enhanced stability while reducing particle
Baghbanzadeh et al.60 silicon−MWCNT H2O aggregation.
Paul et al.61 Al−Zn EG A more commonly utilized method for producing nanofluids
Munkhbayar et al.62 Ag−MWCNT H2O is the two-step approach (Figure 4), which is deemed simpler
Batmunkh et al.63 Ag−TiO2 H2O
Arani and Pourmoghadam64 Al2O3/MWCNT EG
Farajzadeh et al.65 Al2O3/TiO2 H2O
Esfe et al.66 MgO−SWCNT EG
Giwa et al.67 γ-Al2O3/MWCNT H2O
Giwa et al.68 MgO−ZnO H2O

2
nanofluid = (1 + 2.5 + 6.25 ) base fluid (3)
42

[(1 ) base fluid

·Cpbase fluid + nanofluid
·Cpnanofluid ]
Cpnanofluid =
nanofluid (4)
43
Figure 4. Two-step process.

UDh and more cost-efficient. This technique is preferred for creating

Reh = nanofluids composed of oxides.78 The process entails
(5)
converting nanoparticles into a powdered form using chemical,
Cp physical, or biological methods and then dispersing the powder
Pr = in a base liquid. Uniform and stable nanofluids are typically
k (6)
achieved through ultrasonic agitation, ball milling, and
hDh magnetic stirring.79 Due to the straightforward and economical
Nu = nature of producing nanopowders, this method is potentially
k (7)
suitable for commercial industrial applications. However, the
L V2 two-step process often leads to poor dispersion of the
P=f nanoparticles. Thus, researchers have introduced additional
D 2 (8)
steps to enhance dispersion quality and minimize aggrega-
1/3 tion.75 These supplementary measures may involve the use of
Nu ijjj f yzzz surfactants80,81 surface modification or functionalization,82,83
PEC = j z
Nusmooth jj fsmooth zz pH adjustment,84 and others. Many experiments have utilized
k { (9)
this approach due to its potential in commercial and industrial
2.2. Nanofluid Preparation. The perfect colloidal settings.85−89 Challenges, however, are present with the two-
suspension containing nanoparticles requires even distribution step approach, such as swift settlement, additional stages, and
and excellent stability. However, because of these particles’ elevated surface energy.90 The difference in the above to
high surface area and energy, they tend to clump together and nanofluid preparation has been depicted in Figure 5.
settle in the liquid, impacting the HT properties of the fluid.69 The assessment of colloidal suspensions involves a range of
Therefore, achieving a stable suspension of nanofluids is characterization examinations, including Scanning Electron
crucial. The stability of these fluids is subjective to the Microscopy, Transmission Electron Microscopy, Differential
preparation process, whether it be a one-step approach70,71 or Scanning Calorimetry, and other analyses aimed at studying
a two-step process.72−74 the configuration, composition, and attributes of the nano-
In Figure 3, the single-step process involves the thermal particles.87 In addressing the issue of nanoparticles’ instability,
breakdown of nanoparticles under reduced pressure.75,76 This stability assessments are crucial, as clustering could potentially
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Figure 5. Advatages and disadvantage of (a) one-step and (b) two-step nanofluid preparation. Reprinted with the permission of Ho et al.88
Copyright 2023 Elsevier Inc.

disrupt thermal mechanisms. To avert nanofluid agglomeration determines the stability of a nanofluid.96−98 Enhancing the
and guarantee peak efficiency, multiple stability tests must be repulsive forces between particles is essential for maintaining
conducted. stability.
2.3. Nanofluid Stability. Particles at the nanoscale in 2.4. Stability Enhancement Methods. 2.4.1. Surfactant
liquids experience intricate stress conditions and have a high Addition. A nanofluid liquid typically involves a pair of
level of surface activity, making them susceptible to self- elements. These consist of nanoparticles and basic fluid. The
polymerization when in basic liquids. Once aggregated stability of nanofluid depends on the kind of nanoparticles and
particles reach a certain size, these nanoparticles settle, leading the base fluid. Nanoparticles may be hydrophobic or
to an uneven dispersion of particles. This instability at a larger hydrophilic, while base liquids might be polar or nonpolar.
scale affects the flow behavior and HT properties of the liquid- Different types of surfactants are shown in Figure 6.
containing nanoparticles. Over time, the polymerized particles
settle out of the liquid. Techniques such as using the
appropriate electrolyte as a dispersant, adding surfactants,
and applying ultrasonic vibrations during dispersion help
address nanofluids’ suspension stability issues. In sedimenta-
tion testing, the suspension’s stability is assessed by capturing
sedimentation images in a tube using a camera. Although the
settling process is visible, ultrasonic vibrations can disrupt the
nanoparticle interactions. Dispersants create a repulsive force
between particles, reducing their tendency to clump together
and settle as particle swarms.73 Stability issues stemming from
interactions between particles and with the liquid are a
significant concern for nanofluids; other factors, such as
temperature and magnetic fields, can also impact nanofluids’ Figure 6. Types of surfactants.
stability.91
The intensity of the magnetic field is significant for
nanofluids. Hong et al.92 studied how the strength and Particles, generally hydrophilic like oxide particles, are easily
duration of magnetic fields affect nanofluids’ kp. When mixed into polar fluids like water, and hydrophobic particles
magnetic nanoparticles (Fe2O3) are subjected to a magnetic like CNT can be mingled into nonpolar base liquids such as
field, they create networks and align along the field’s direction, oils without needing a third element. Nonetheless, surfactants
increasing physical interaction and higher kp. They observed a must be included to anchor the nanoparticle if hydrophobic
35% boost in thermal conductivity without a magnetic field. particles are blended into polar base fluids.
However, lengthy exposure to the magnetic field triggered the Surfactants are generally of four types: anionic, nonionic,
accumulation of large particle clusters over time, reducing kp. cationic, and amphipathic. Amphipathic substances have
The magnetic field weakens the opposing force between positive and negative hydrophilic groups, which can create
suspended particles, causing them to clump together. Chang et positive/negative elements according to the pH of the fluid.
al.93 inspected the impact of magnetic fields on the stability of They possess germ-repelling qualities, resilience to water
CuO nanofluids and found that stability deteriorated more hardness, and little toxicity.91
quickly with a magnetic field present. This led to particle The creation of bubbles is a drawback of surfactants,
aggregation and the formation of larger particles. impacting the heat characteristics of the liquid. Introducing
Similarly, Zhang et al.94 looked at how particle ϕ affects the surfactant into the nanofluid may enhance its stability, but the
stability of SiO2 (water-based) nanofluids. They noted that adverse impact on the surfactant is magnified in high-
higher ϕ led to poor initial stability, resulting in agglomeration temperature scenarios (Table 3).
and decreased efficiency in heat transfer.95 The balance Zeta potential measures the repulsion between nano-
between van der Waals forces causing agglomeration and the particles, which is represented in millivolts. The particle’s
electrical double-layer repulsion force separating particles charge determines whether the zeta potential is positive or
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Table 3. Effect of Different Surfactants on Stability

researchers nanofluid surfactant zeta potential value (mV)
Chakraborty et al.99 Cu−Zn−Al/water none 38.6
Wang et al.100 Al2O3/water SDBS −40.1
Sandhu et al.101 Al2O3/water−EG none 57
Ahammed et al.102 graphene/water SDBS −63.7
Srinivas et al.103 CNT/water none 20.5
Hwang et al.104 carbon black/water SDS −26.9
Mostafizur et al.105 SiO2/methanol none −40
Ghadimi et al.106 TiO2/water none −33.3
Gupta and Sharma107 Cu−CNT/water none −46.6
Xian et al.108 TiO2/water−EG SDBS −60
Li et al.109 Cu−water CTAB 28.1
SDBS −43.8
TX-10 −8.3
Khairul et al.110 CuO/water none 28
SDBS −85.1
Cacua et al.111 Al2O3−water none 30
SDBS 20
CTAB 32
Choudhury et al.112 Al2O3−water none 14
SDS −30
Song et al.113 stainless steel−water SDBS −70
CTAB 60.1
Chakraborty et al.114 Cu−Zn−Al−water SDS −50.6
Tween 20 24.3
Ghadimi et al.106 TiO2−water None −33.3
SDS −55
Jiang et al.115 CNT/water None −30
SDS −40
Yılmaz Aydın et al.116 Dolomite−water SDBS 30
Triton X-100 26

negative. Nanofluids with a high zeta potential are considered the surfactants in nanofluids or that the size of nanoparticles
to be electrically stable. Precipitation occurs rapidly at zeta could decrease with increased sonication time. A few proposed
potentials between 15 and 30 mV, stability is achieved at 30 guidelines include utilizing a cooling bath, operating in pulse
mV, and excellent stability is observed at 45 mV. Kim et al.117 mode, and employing cylindrical-shaped flat-bottom beakers.
created a nanofluid with gold/water without surfactants and Nanofluid with gold/water was created by Chen and Wen119
assessed its stability through zeta potential measurements. The by varying the sonication periods from 10 to 60 min, and a
zeta potential for nanofluids with nanoparticle ϕ of 0.018 vol% reduction in agglomerated particles was noted as the sonication
showed −32.1 mV, and 0.0025 vol% showed −38.5 mV. time increased. However, no change in particle size was
Mondragon et al.118 investigated the consequence of ϕ of silica observed after 45 min. Mahbubul et al.120 applied ultra-
nanoparticles. Results indicate a −16 mV with a nanoparticle sonication for various durations (30, 60, 90, 120, 150, and 180
concentration of 2 wt % and -48.63 mV with a mass min) to TiO2/water nanofluids and determined that the
concentration of 20 wt %. Nanofluids with a concentration optimal sonication time for maximum stability is 150 min.
of 20 wt % showed stability for at least 48 h. Exceeding 150 min of sonication led to nanoparticles
2.4.2. Ultrasonication. The ultrasonic mixing technique reagglomerating. Azmi et al.121 agitated a TiO2/water-ethylene
utilizing ultrasonic waves in a nanofluid improves its stability glycol (60:40) nanofluid on a magnetic stirrer for 30 min tailed
by overcoming the force of gravity acting on the nanoparticles. by 2 h in an ultrasonic bath. They confirmed the stability of the
To extend the enduring lifespan of nanofluids, ultrasonication nanofluid for over 7 months through stability analysis using
has garnered widespread adoption and is recognized as a FESEM and TEM. Mahbubul et al.122 dispersed 0.5 vol.% of
pivotal stage in nanofluid production via the two-step method. Al2O3 nanoparticles in water using ultrasonication for varying
Nevertheless, there remains a lack of standardized protocols for durations from 0 to 5 h and examined the nanoparticle
nanofluid preparation, particularly regarding the optimal distribution through electron microscopy. The scholars
duration for achieving homogeneity, the requisite power observed that longer ultrasonication times were necessary to
amplitude of the sonicator, and the appropriate types or attain improved stability and decreased viscosity. TEM analysis
durations of pulse modes to be employed. Researchers have indicated superior particle dispersal after 2 h of ultrasonication.
encountered conflicting findings regarding the impact of Additionally, an external force like ultracentrifugation is
ultrasonication duration on the colloidal dispersion of employed for the separation and purification of nanoparticles,
nanoparticles. While some argue that longer ultrasonication relying on particle deposition induced by the centrifugal force
durations are advantageous for achieving proper nanoparticle from the rotation of the ultracentrifuge.123 Figure 7 represents
dispersion, others suggest that prolonged sonication may harm microstructure after 1 h of ultrasonication with different vol%.
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adding a surfactant, another method to enhance the stability of

nanofluids involves pH control. Adjusting the pH of the
nanofluid can result in a stable suspension by manipulating
strong repulsive forces.
Adjusting the pH of a nanofluid can be achieved by adding
an appropriate nonreactive acidic or alkaline solution.124
Changes in flow patterns occur with fluctuations in nanofluid
pH. However, pH alterations in nanofluids have other effects as
well. Recent studies have indicated that pH variation is crucial
for improving nanofluid stability, kp, and μ.
Azizian et al.124 studied how pH affects TiO2/water
nanofluid stability and kp, noting particle aggregation as a
key factor in thermal enhancement. Zhang et al.125 suggested
adding NaOH or HNO3 to control the pH of TiO2/water
nanofluids.
Wang et al.126 explored the impact of pH on Al2O3/water
and Cu/water nanofluids, determining pH levels of 8 and 9.5
Figure 7. TEM images showing the microstructure of 1 h as optimal for each respectively. At these ideal pH levels, kp
ultrasonicated Al2O3−water nanofluids of (a) 0.01, (b) 0.1, (c) 0.5, improvements of up to 15% for Al2O3/water and 18% for Cu/
and (d) 1 vol.% concentrations. Reprinted with the permission of water nanofluids were achieved at a 0.8% weight fraction. Zhu
Mahbubul et al.123 Copyright 2015 Elsevier B.V. et al.127 investigated pH’s impact on Al2O3/H2O nanofluid
behavior, noting a 10.1% increase in effective kp at a pH of 8
2.4.3. pH Control. Nanoparticles tend to aggregate more with a 0.15 wt % particle concentration. Said et al.128 applied
readily because of their elevated surface energy, posing pH-treated Al2O3/water nanofluids to a solar collector,
challenges for achieving uniform dispersion within fluids. observing improved energy and exergy efficiency.
Hence, mitigating nanoparticle aggregation in the liquid has Various techniques for preparing stable nanofluids have been
emerged as a crucial concern for facilitating stable nanofluid compared, showing that the effectiveness of these methods
formation, which is essential for efficient HT. In addition to may vary based on the nanoparticle type, base fluid type,

Table 4. A Few kp Mathematical Equations of Nanofluids

author mathematical equation conclusions

Maxwell129 (k p + 2k f + 2 (k p kf ) spherical nanoparticles of various vf
knf = (k p + 2k f 2 (k p
k
kf ) f

Hamilton and k p + (n 1)k f + (n 1) (k p k f ) cylindrical and spherical nanoparticles

Crosser130 knf = k p + (n 1)k f (k p k f )

Bruggeman131 (3 1)
kp
+ [3(1 ) 1] +
effective knf of mixed bodies from isotropic substances
k nf kf
kf
= 4

Patel et al.132 ÅÄÅ ÑÉÑ

ÅÅ 2kBTdp ÑÑ microconvection model for kf of nanofluids
keff
=1+
kpdf
ÅÅ1 + c 2Ñ
Ñ
kf )Å
kfdp(1 ÅÅÇ f f dp
Ñ ÑÑÖ
Rea et al.133 knf = kf (1 + 4.5503 ) model obtained using experimental data
134 ÅÄÅ k p df Ñ
É
Ñ
= ÅÅÅÅ1 + k (1 )d ÑÑÑÑ
Eastman et al. keff a generic model
kf ÅÅÇ f pÑÑÖ
Evans et al.135 keff kp a model established on particle kf
kf
=1+ p 3k
f

Singh et al.136 knf = kf (1 + 4 ) modified Hamilton−Crosser model

Khanafer and i 47 y based on experimental works
+ 2.4375 jjj d (nm) zzz
k nf kp
Vafai137 kf
= 1 + 1.0112
k p {
0.0248 p ( )
0.613

Lu and Lin138 keff

=1+a +b 2 composites with oriented spheroidal particle
kf p p

Wang et al.139 k 3fq(p) / p0 based on the size of the nanoparticle, vf, shape, nanolayer, and interaction
kf
=1+ 1 fq(p) / p0 between nanoparticles
Sundar et al.29 knf = kbf (1 + 10.5 )0.1051s effective for the Fe2O3 nanoparticle within a specified temperature range and
vf range
Wang et al.140 (3 1)
kp
+ [3(1 ) 1] +
a hypothetical model for estimating the efficient coefficient of flow of a
B
keff kf solution containing nanoparticles
kf
= 4

Afrand et al.141 k nf 0.323 a model developed by curve fitting of data and based on a magnetic nanofluid
k bf
= 0.7575 + 0.3 T 0.245

Khndher et al.142 k nf 0.0074 0.036 based on temperature or particle vf

k bf
= 1.268 ( 80T ) ( 100 )
Zaraki et al.143 k nf a low vf nanoparticle model was constructed using experimental data (φ <
k bf
= 1 + Nc 5%)

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Table 5. Nanoparticle vf Impact on HT Features

articles vf findings
Reza et al.157 0% ≤ ϕ ≤ 20% introducing more nanoparticles in the flow lowers the shear stress and enhances the HT rate
Fares et al.158 0% ≤ ϕ ≤ 8% raising the vf of nanoparticles increments the average Nu, especially for high Ra values
103 ≤ Ra ≤ 106
Parvin et al.159 0% ≤ ϕ ≤ 15% increasing the nanoparticle vf accelerates heat transmission
Gr = 104
Pr = 6.2
Mebarek-Oudina160 0% ≤ ϕ ≤ 10% incrementing the vf of nanoparticles in various base fluids improves the hm and yields a strong HT
Ra = 104
Zaim et al.161 0% ≤ ϕ ≤ 4% HT performance is at its highest for important nanoparticle vf; when conduction drives the flow, the effect of
103 ≤ Ra ≤ 106 nanoparticles is more prominent
Chamkha et al.162 0% ≤ ϕ ≤ 10% although HT is boosted when increasing the nanoparticle vf, the ratio of entropy to Nu appears to increase as well
Ganesh et al.163 0% ≤ ϕ ≤ 8% the strength of the Nu number and HT is related to the nanoparticle vf
Raza et al.164 1% ≤ ϕ ≤ 10% altering the solid concentration of nanoparticles can adjust the nanofluid temperature
Dogonchi et al.165 0% ≤ ϕ ≤ 4% improving the Nu number requires a high kp that can be obtained by enhancing the nanoparticle vf
Chamkha et al.166 0% ≤ ϕ ≤ 5% enhancement of HT is achieved by the incorporation of nanoparticles, resulting in an increased average Nu
Ra = 105
Mebarek-Oudina et 0% ≤ ϕ ≤ 5% the growth of the HT rate is led by the dispersion of nanoparticles, especially those with high thermal conductivity
al.167 Ra = 104

nanoparticle concentrations, and sonication duration.144 ature swing, parallel plate, and optical techniques, can assess
Increasing sonication time or power reduces cluster size and nanofluid kp. Multiple factors affect kp, including nanoparticle
increases particle suspension stability. ϕ, nanolayer presence, nanoparticle size, temperature, and type
Nevertheless, very high and prolonged sonication power of base fluid. Several theoretical models have been devised to
may not show the same results. Ultrasonic devices can elevate predict the kp of nanofluids, some of which are listed in Table
nanofluid temperature, but ambient temperature also plays a 4. These models are constructed based on classical theories like
role, resulting in diverse nanofluid products based on location Maxwell129 and Hamilton-Crosser models,130 considering the
and weather conditions. Therefore, determining the optimal conductive properties of spherical and nonspherical particles
sonication period and power level that enhances nanofluid within the mixtures. Experimental models like the Rea133
stability is crucial. Surface modification methods are complex model and Afrand141 correlation have also been designed to
and expensive, so they are not ideal for industrial use. estimate the kp ratios of specific nanofluids under varying
Establishing stable nanofluids through pH management is conditions. Overall, the effectiveness of these models in
simpler and more cost-effective. predicting kp relies on factors like particle ϕ, temperature, and
In nanofluids, extremely low or high pH levels can originate base fluid properties. Further research and experimentation are
either acidity or alkalinity, damaging HT equipment and needed to enhance our understanding of the thermal behavior
restricting practical applications.145 Surfactants connect nano- of nanofluids and optimize their applications in HT systems. kp
particles with base fluids, enhancing nanoparticle dispersion by can be altered by changing factors like size/shape and type of
reducing base fluid surface tension. The presence of surfactants the nanoparticles/basefluid.
in nanofluids at elevated temperatures can lead to foaming and 2.5.2. Nanoparticle ϕ Effect on kp of Nanofluids. The
blockages in pipes. Over time, using nanofluids containing thermal efficiency of thermal systems can be enriched by
surfactant at extremely high temperatures leads to malfunctions incorporating nanoparticles of an optimal size. However,
in thermal devices. particle agglomeration can begin as the ϕ of particles increases,
2.5. Characteristics Concerning the Transfer of Heat leading to a decrease in kp. Higher vf and larger particle size
in Nanofluids. Recently, there has been a growing trend can contribute to agglomeration and sedimentation, increasing
toward using novel types of working fluids that incorporate μ intensifying HT surface fouling. This fouling phenomenon
particles of nanoscale materials dispersed within the base liquid and increased μ can lead to higher Δp and greater pumping
(such as water, deionized water, ethylene glycol, etc.) for HT power demand, ultimately reducing the overall THP compared
purposes. This is because these nanofluids have a significant to conventional fluids.147−149 To achieve high HT with
impact on the thermal characteristics of the base fluid. minimal Δp, it is crucial to determine the ideal vf of
Different nanomaterials influence the base fluids’ thermal nanoparticles with high kp. Maintaining maximum HT
properties in varying ways. Factors like nanoparticle size, efficiency and minimizing pumping power demand is essential
shape, and ϕ are vital factors that can significantly alter the for designing energy-efficient thermal systems.
thermal properties.146 In an experimental study by Goodarzi et al.,150 the thermal
2.5.1. Thermal Conductivity. The key factor for efficient efficiency and Δp in a double pipe HX were analyzed using
HT systems is nanofluids’ kp, which surpasses traditional fluids. nitrogen-doped graphene (NDG) nanofluids at different ϕ of
Nanoparticles in nanofluids exhibit greater kp due to their nanosheets (0.01−0.06%). The outcome exhibited that adding
Brownian motion, where collisions with fluid molecules nanosheets with water improved the HT rate of the nanofluid,
enhance thermal properties. Nanoparticle size and forming a achieving a 15.86% augmentation at a 0.06% ϕ of nanoparticles
nanolayer near solid particles influence this phenomenon. The in NDG nanofluid. The researchers established that higher Re
base fluid’s thermal properties affect the nanofluid’s kp. Various and particle percentages could increase the f, leading to
methods, including hot wire, transient plane welding, temper- elevated Δp and demand for pumping power. Akhavan-
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Figure 8. Different nanoparticle shapes generally added to the base fluid. Reprinted with the permission of Mahian et al.170 Copyright 2014 Elsevier
B.V.

Figure 9. TEM image showing the morphology of TiO2 nanoparticles of different shapes: (a) spherical, (b) elliptical, (c) cubed, (d) sheet.
Reprinted with the permission of Cui et al.171 Copyright 2021 Elsevier B.V.

Figure 10. Variations in (a) kp and (b) μ of the SiO2−water nanofluids as a function of temperature and particle size. Reprinted with the
permission of Zhang et al.169 Copyright 2021 American Chemical Society.

Behabadi et al.151 studied the HT and Δp in an HX using copper surfaces coated with a low mass ϕ, with an increase in
nanofluid (MWCNTs-water) of various particle ϕ (0.05− ϕ leading to a surge in surface roughness. In another study by
0.2%). They noted that the hm of the nanofluid surpassed that Garbadeen et al.,156 the free convection using nanofluids
of the base fluid and rose with higher particle ϕ. (water-MWCNT) in a square duct with differentially heated
Ezekwem and Dare152 created SiC/DW and SiC/EG side walls was experimentally investigated, showing a
nanofluids with vf ranging between 0.5 to 5 vol %. The kp of significant improvement in HT with an optimal nanoparticle
the nanofluids was assessed, showing enhanced kp with vf of 0.1 vol %. A few of the research on ϕ effect on HT can be
increased nanoparticle ϕ. Further, Suresh et al.153 concluded
accessed in Table 5.
from their study that nanoparticle ϕ of hybrid nanofluids
2.5.3. Effect of Nanoparticle Size and Shape on the
(Al2O3−Cu/water) directly impacts kp.
In a study by Akhavan-Zanjani et al.,154 it was found that Thermal Conductivity of Nanofluids. The size of nano-
even small amounts of graphene at a concentration of 0.02 vol particles impacts the viscosity, thermal conductivity, and
% could boost water’s kp by more than 10%. Kiyomura et al.155 density of nanofluids. Reducing nanoparticle size improves
examined the performance of boiling HT on surfaces coated the thermophysical properties of nanofluids.168,169 Further-
with Fe2O3 nanoparticles in Fe2O3 nanofluid (water-based) at more, the primary factors that influence the thermophysical
high ϕ (0.29 g/L) and low ϕ (0.029 g/L). The research properties of nanofluids encompass nanoparticle morphology
indicated that the maximum kp values were observed on and concentration.
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Table 6. A Few μ Models of Nanofluids

authors mathematical equation conclusions
Einstein180 eff
= (1 + 2.5 ) 0.05 particles shaped like spheres with a volume concentration of 2% or below
Brinkman181 eff
= eff extension of Einstein model
f (1 )2.5

Bruijn182 eff
= 1 + 2.5 + 4.698 2 spherical particles
f

Batchelor183 = (1 + 2.5 + 6.5 2) model developed keeping in mind the interaction taking place between particles
eff 0
184
Wang et al. eff
= 1 + 7.3 + 123 2 a generic model
f

Dávalos-Orozco et al.185 = (1 + 2.5 + 6.17 2) nanoparticles volume concentration involved

eff f
186 2
Nguyen et al. = (1 0.025 + 0.015 ) statistical technique called curve fitting to analyze experimental data
nf 0
187
Abedian et al. =
bf model for suspended particles
nf (1 2.5 )
188
Heyhat et al. model for a specific range of temperatures, sizes of particles, and ϕ
nf =
5.989
0 (T )exp 0.278 ( )
Esfe et al.189 nf
= 1 = (0.1008 × 0.69574
× dp0.44708 ) developed considering the particle diameter of the Fe−water nanofluid
bf

Hamid et al.190 0.2321 a chosen nanoparticle concentration and temperature range model
r
=
nf

bf
= 1.42(1 + R ) 0.1063
( 80T )
Zaraki et al.143 nf
= 1 + Nv × a diluted nanofluid model was formulated, using Nv to represent the parameter of
bf viscosity

They can be synthesized in various sizes ranging from 5 to Sundar et al.173 revealed that a 2.0% vf at a temperature of 60
100 nm. The shapes of nanoparticles commonly employed in °C resulted in a rise 2.96 times higher than the original fluid.
base fluids (as depicted in Figure 8) were demonstrated to Furthermore, the μ enhancement can alter based on base fluid
directly influence solely the viscosity and thermal conductivity types. The μ boost declined as ethylene glycol percentage in
of the resultant nanomaterials.170 the mixture increased.174 Naik and Sundar175 studied the
Cui et al.171 conducted an experimental investigation into temperature effect on the kp of CuO nanofluid utilizing a
the thermal conductivity of nanofluids featuring various mixture of water and propylene glycol (30:70%) as the base
nanoparticle configurations, as depicted in Figure 9. The liquid. They found that as the temperature rose from 298.15 to
findings indicated that the relative thermal conductivity (RTC) 338.15 K, so did the kp from 10.9% to 43.37% for a vf of 1.2%.
of TiO2/water nanofluids containing clubbed and sheet-shaped Buonomo et al.176 studied the effects of temperature rise of
nanoparticles surpassed that of other shapes. Specifically, TiO2 nanofluid (Al2O3-water) on the kp at different levels of particle
nanofluids containing sheet nanoparticles exhibited the highest ϕ. They found that the enhancement in kp of the nanofluid
RTC at 60 °C and a nanoparticle concentration of 4%. became more pronounced as the temperature rose. Their
Further, the effect of particle size by Zhang et al.169 who results indicate that for particle ϕ of 0.5% at 25 °C, the
examined how particle size influences the thermal transfer increase in kp ranged from around 0.57% to approximately 8%
efficiency of SiO2−water nanofluids. They meticulously crafted at 65 °C. Additionally, with vf of 4%, the rise in kp was from
suspensions with commendable stability and dispersion and 7.6% to 14.4%, with a temperature rising between 25 to 65 °C.
assessed their kp through the transient hot wire technique. The 2.6. Effect of μ. The role of μ in nanofluids is comparable
findings unveiled that the kp of SiO2−water nanofluids with to that of kp in HT applications. When nanoparticles are
particle sizes measuring 15, 30, and 80 nm surpassed those of introduced, the μ of the base liquid undergoes changes. The
water by 7.80%, 4.90%, and 3.80%, respectively. Moreover, it greater μ of nanofluids causes a surge in the Δp during
was noted that smaller nanoparticle sizes in the nanofluid pumping. Several factors affect the μ of nanofluids, such as
resulted in elevated dynamic viscosity values compared to the temperature, particle ϕ, size and shape of nanoparticles, shear
base fluid, as depicted in Figure 10. stress, presence of surfactants, type of base liquid, tendency for
2.5.4. Temperature Effect on the kp of Nanofluids. nanoparticle agglomeration, and the specific type of nano-
Research has indicated that temperature impacts kp, which particles used.177 μ tends to decline with rising temperature
rises as temperature increases. The overall μ of nanofluids due to changes in intermolecular forces. Adding surfactants can
comprises two components: static and dynamic. The Einstein increase the μ of nanofluids.178 Common techniques for
model and the influence of nanolayer formation combine to measuring nanofluid μ include vibrating, rotating, capillary,
create the static element of the nanofluid μ. The μ impact orifice-type, and bubble viscometers.179 Various models for
caused by the nanolayer surrounding a nanoparticle is predicting nanofluid viscosity can be found in Table 6.
heightened due to its 1 nm thickness. In contrast, the dynamic 2.6.1. Nanoparticle Size Affecting μ of Nanofluids. The
aspect is attributed to the μ influence due to Brownian motion impact of nanoparticle size in nanofluids on μ has produced
associated with nanoparticles.172 A decrease in μ at elevated varying results in various studies. Some research shows that
temperatures is a result of the expanding intermolecular nanofluid μ increases as particle size grows,191,192 whereas
distance within the base fluid at elevated temperatures. As other studies suggest that viscosity rises as nanoparticle size
nanoparticles heat up, their bond with the surrounding fluid decreases.193,194 He et al.195 inspected how μ of nanofluids
weakens. The rise of μ in nanofluids rises more quickly with (TiO 2 −water) of varying particle sizes and ϕ. They
increasing temperatures than in the base fluid. This determined that as particle size and ϕ increased, the relative
phenomenon is more pronounced at larger ϕ. A study by μ of nanofluids also increased. Nguyen et al.196 utilized
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nanoparticles (Al2O3) of 36 and 47 nm when creating a water- HX. One such application is solar collectors, and in recent
based Al2O3 nanofluid. The result indicates that particle size years numerous nanofluids have been employed to enhance
had a profound impact at higher Vf concentrations (>4%), with THP in solar energy technologies to achieve this. The
nanofluid μ being higher using smaller nanoparticles than enhancement in HT and reduction in f should be considered.
larger ones. This conclusion indicated that the μ of the The ratio of the enhancement rate indicating the surge in
nanofluid with 47 nm particle size at higher ϕ was greater than HT to f is known as THP. Equations 10 and 11 present the
that of the nanofluid with 36 nm particles. They found that μ primary criteria for evaluating the THP of the thermal
increased as particle size rose at higher ϕ. Anoop et al.197 system.206−214 Models above a THP of 1 are considered
prepared a nanofluid (Al2O3−water) using nanoparticles of 45 advantageous, whereas models below this threshold are
and 150 nm in an experimental study. The results of μ deemed unfavorable. The flow and thermal characteristics of
measurements revealed that the nanofluid with 45 nm particles nanofluids play a crucial role in evaluating and enhancing their
had higher μ than the one with 150 nm particles. In summary, performance. Thermal properties, including kp, μ, and ρ are
they suggested that smaller nanoparticles led to a greater influenced by multiple constraints such as Re, f, and pump
increase in μ. Based on these studies, it can be determined that efficiency.215 The factors impacting THP are illustrated in
nanofluid μ is heavily influenced by particle size. Figure 11.
2.7. Heat Capacity. The Cn capacity is a critical factor for
nanofluid that impacts its HT rate, as it is closely connected to
energy storage, transfer, and the Pr. Both the base fluid and
particles of a nanofluid play a role in determining its Cn
capacity. Generally, the nanofluid’s Cn capacity decreases as the
nanoparticle concentration increases. Kumerasan and Velraj198
experimented with MWCNT/EG−water nanofluid and
observed that adding CNT to the base liquid surges the Cn
capacity. However, they found that the Cn capacity decreased
as the ϕ of nanoparticles increased. Yarmand et al.199 studied
the Cn capacity of carbon−graphene/EG nanofluid, revealing
that the Cn capacity increased with higher temperatures and ϕ
of the nanoparticle. According to a study by Shin et al.,200 the
addition of carbon nanotubes at a mass fraction of 1% surges
the Cn capacity of the eutectic salt Li 2CO3/K2CO3 by 19%.
Research shows that both nanoparticle ϕ and temperature
significantly affect Cn capacity.
A key drawback of thermal energy storage systems is the low
Cn of the working fluid in use. It is essential for the fluid
employed as a refrigerant to have a high Cn capacity,201
especially for smaller-size HXs.202 Therefore, enhancing the Cn
of nanofluids is a persistent issue. One method to achieve this Figure 11. Factor effecting THP.
is by using nanoencapsulated phase change materials
(NEPCMs) in the formulation of nanofluids. NEPCMs are a
type of nanofluid where the nanoparticles consist of a core and Numerous research has delved into the effects of factors like
a shell, with the core made of PCM capable of undergoing a μ, Re, Δp, mf, and flow pattern on the thermal performance of
phase change (solid−liquid) and absorbing or releasing energy nanofluids. μ plays a crucial role in determining the hm of
based on latent heat (energy stored) during phase change. In nanofluids. The properties of the fluid change significantly with
another study, Ghalambaz et al.203 found that nanoencapsu- increasing μ. Typically, the μ of a nanofluid is much higher
lated phase change material (NEPCM) particles enhanced HT than the base fluids, resulting in higher υ and pumping power
performance in a cavity by increasing the Cn capacity. This was at consistent Re. It is important to consider pumping power
attributed to the higher latent heat storage at the core with when comparing the practical efficiency of fluids. This is
PCM. Other researchers have also incorporated NEPCM because the practical efficiency declines as the solid content in
particles in different systems, including eccentric annuli, mini- the fluid rises. Asirvatham et al.216 examined the HT
channel heat sinks, double pipe HX, and inclined porous performance of HX with nanofluids as working fluid under
cavities.201,202,204,205 countercurrent with various flow conditions from laminar to
2.8. THP of the Thermal System with Nanofluids. The turbulent. Their outcome exhibited a rise in hm by up to 28.7%
significance of the THP of a system is on the rise. As a result, and 69.3% upon adding silver nanoparticles by 0.3% and 0.9%,
alternative approaches to enhance THP in such fluid dynamics respectively. However, some research suggests that HT
are being sought. These approaches involve strategies about efficiency of nanofluids may decline with the addition of
the spatial configuration of pipes, commonly called passive nanoparticles, regardless of ϕ of the nanoparticle.
techniques for enhancing HT and enhancements in fluid (Num/Nuf )
characteristics. =
Using pipe bundles for fluid flow is common in industrial (fm /f )1/3 (10)
t
processes such as cooling/heating. The utilization of nanofluid
2/3
is also growing steadily to boost HT in thermal systems. (Num /Nuf ) hm /hf ji zyz
1/3
ij yz
j mz
× jjjj × jjjj z
f f
Substituting conventional working fluids with nanofluids is an = = × zz zz
(fm /f )1/3 ( Pm/ Pf )1/3 j zz j zz
efficient method for heightening the THP of various types of t
m k m{ k f{ (11)

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Table 7. Properties of Nanofluids with Water as a Base Liquid at 298 K

Al2O3 + H2O CuO + H2O TiO2 + water
properties base fluid (H2O) 0.4 0.8 1 0.4 0.8 1 0.4 0.8 1
ρ 998.2 1010 1021 1027 1020 1042 1053 1011 1024 1030
Cn 4182 4128 4075 4050 4089 3999 3956 4123 4065 4037
Kp 0.6 0.606 0.61 0.617 0.606 0.61 0.616 0.605 0.611 0.614
μ 0.001 0.00098 0.00021 0.001 0.0009 0.001 0.001 0.0002 0.0002 0.0002

In a study by Mikkola et al.,217 the effect of particle trapezoidal-corrugated channels, along with a straight channel.
characteristics on nanofluid kp was examined. Various water Their findings indicated enhanced performance in nanofluids
polystyrene, SiO2, and Al2O3 nanofluids were investigated with compared to base fluids, with HT and Δp increasing with SiO2
vf ranging from 0.1 to 1.8 vol %. Heating experiments were Vf. The use of a corrugated channel improved HT rates, Δp,
conducted in a tube HX with Re ranging from 1000 to 11,000. and thermal performance significantly compared to straight
The findings indicated that higher nanoparticle vf led to channels.
decreased thermal conductivity. Aliabadi et al.,218219 produced Qi and colleagues225 studied HT and f characteristics of
a nanofluid (Cu−water) with a weight fraction ranging from nanofluids in circular and elliptical tubes (horizontal),
0.1 to 0.4%, used in plate-fin HX and compared it with HX examining mass concentration effects. They discovered that
with VGs. They noticed that the combination of VG and TiO2−water nanofluid with 0.5 mf increased Nu compared to
nanofluids showed a TEF of 1.67. Their findings indicated that water in both tube geometries.
lower nanofluid ϕ led to superior results. Further exper- Ajeel et al.226 delved into the effects of Vf of nanofluid and
imentation on corrugated MHS (water-cooled) with different HX geometric parameters on the TPF of curved-corrugated
configurations of the fin(plate/plate-pin) employing Al2O3 − channels with CuO/MgO-water (nanofluid) as the working
water nanofluid with various weight fractions (0.1−0.3%) with fluid. They found that increasing Vf, BR, and decreasing PR
Re between 100−900. Upon comparing different fin designs, a improved the THP, with optimal results observed at specific
peak THP of 1.84 at 0.3 wt % was noted for sinusoidal plate- PR. The THP of a radiator using hybrid nanofluids was
pin finned slotted MHS. investigated by Sahoo and team,227 highlighting the significant
Sarafraz et al.220 explored the THP of a rectangular impact of particle shape on the system’s performance, with the
microchannel with Ga−CuO nanofluid. They examined the radiator system’s performance index declining with higher
consequences of ϕ and nanofluid flow mf on the system’s hm, coolant flow rates and Vf of hybrid nanofluids.
Δp, and THP. They disclosed that Re substantially influenced Recent research has focused on the impact of magnetic fields
the THP and the nanofluid ϕ; additionally, they attained the on the THP of magnetic nanofluids. Fan et al.228 studied the
highest THP in the laminar regime due to minimal Δp. kçay et THP of Fe3O4-water-arabic gum nanofluids used in a novel HX
al.221 found that while there is no improvement in THP at low system with a corrugated tube and perforated turbulator. They
frequency and intensity, a specific frequency exists that found that high nanoparticle mf, magnetic flux density, bilateral
maximizes THP. By optimizing THP at high intensity and a staggered magnetic fields, and perforated turbulators can
specific frequency (Wo = 10), pulsating flow greatly enhanced significantly enhance THP. Mei et al.229 investigated the effects
HT, despite increasing f. The researchers noted that as the of paralleled magnetic fields on Fe3O4−water nanofluids in a
frequency exceeds the critical value (Wo = 15), the circular tube, noting that the Nu correlated with nanoparticle
enhancement in THP diminishes due to reduced HT efficiency mf and had an inverse relationship with magnetic induction
and higher f losses. intensity. At the same time, the f increased with both
Sarafraz et al.222 also explored the THP of Ga−Al2O3 nanoparticle m f and magnetic field strength. A few
nanofluid used in solar receiver-made copper rectangular thermophysical properties are represented in Table 7.
microchannel. By varying the mf of aluminum oxide in gallium
to 5, 10, and 15 wt %, they observed that lower energy, f, and 3. APPLICATIONS
pumping power are required despite the small Re, leading to Since the inception of nanofluids in 1995, scholars from
enhanced THP in the laminar regime. The study indicated that various disciplines and countries have rigorously investigated
higher concentrations of Al2O3 increased the hm and Δp their characteristics and possible uses. This collaborative
compared to pure Ga. At the same time, they were using 15 wt endeavor has not only propelled the field of nanofluids
% Al2O3 resulted in decreased THP due to heightened μ and forward but has also yielded remarkable results. These novel
aggregation of Al2O3 nanoparticles in Ga. cooling technologies, unlike conventional coolants, demon-
The type of thermal device used is a crucial factor impacting strate intriguing heat transfer characteristics, with a specific
the THP of nanofluid systems. emphasis on convective heat transfer and thermal conductivity.
In their study, Bahiraei et al.223 examined how a green Figure 12 shows a few fascinating uses of nanofluids.
graphene nanoplatelet nanofluid performed thermally and 3.1. HX. HX are devices that transfer heat between fluids of
hydraulically within a rotating twisted tape tube. They explored different types, with a current emphasis on using nanofluids in
the influence of rotational speed, y, and nanoparticle mf on the various HX. One such HX is HP, an effective tool for moving
system and found that nanoplatelets had little effect on substantial amounts of heat through phase change or vapor
convective HT at higher rotational speeds. Increasing the diffusion. HP is considered one of the most effective passive
rotational speed and mf improved the hm and pumping power, HT technologies on the market and boasts high kt. The steam
while increasing the y had the opposite effect. condenses due to wall temperature difference, releasing latent
Ajeel et al.224 examined the THP of silica nanofluid in heat and enabling the fluid to revert to the evaporator area
corrugated channels, such as semicircle-corrugated and through gravity (thermosiphons) or a capillary wick structure.
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W. Results indicate that DI-Al2O3 is more stable for prolonged

use at a higher heat load of 60W. Khanlari233 examined Al2O3−
SiO2/deionized water hybrid nanofluid and how it affects the
U tubular HX with different flow orientations. He found that
the hybrid nanofluid provided significant enhancements in U.
Variyenli et al.234 prepared nanofluid using fly ash particles
as the working fluid in plate HX, achieving a maximum
enhancement in hm with a nanoparticle weight concentration of
2 wt %. Said et al.235 used CuO/water as the HT fluid in an
Figure 12. Few applications of nanofluids. STHX, demonstrating an increase in the HT and hm. In a plate
HX study, Khanlari et al.236 found that kaolin/deionized water
nanofluid outperformed TiO2/deionized water nanofluid in
The performance of HP is affected by various factors, including
thermal resistance. Vapor bubbles between liquid and solid terms of thermal performance. They observed significant
phases cause thermal resistance in the HP. The large size of enhancements in HT rate with both nanofluids.
bubble cores hinders heat transfer between solid surfaces and A few applications of nanofluids in dual-tube HX are
liquid. Nanoparticles in the working fluid interact with vapor illustrated in Table 8. The initial temperature (Tin) of
bubbles, resulting in smaller nucleation and improved HT nanofluids significantly impacts their HT properties. Zheng
between solid surfaces and liquid in the HP, reducing thermal et al.237 observed that nanofluids containing 0.25 vol % and 0.5
resistance. Aydin et al.230 discovered that utilizing nanofluid vol % Al2O3 in water had 8.27% and 4.84% higher Nu when the
(bauxite-water) decreased the f of HP by 24.3% and inlet temperature was 40 °C compared to 50 °C. For
augmented thermal efficiency by nearly 20.9% when equated nanofluids with 0.15 vol % Al2O3 in water, Nu was 17.7%
with working fluid without nanoparticles. and 10.2% higher at 65 and 55 °C than at 45 °C. In the case of
Jose and Hotta231 numerical transient investigation of 0.05% Al2O3 in water nanofluids, there were increases of 18.2%
wickless heat pipes. A thermosyphon’s thermal behavior was and 13.6% in Nu. The impact of inlet temperature on the kp
examined using CuO and Al2O3 with ϕ of 1 and 5 wt % with and μ of Al2O3 in water nanofluids was similar to that of the mf.
DI water as the base fluid. The findings reveal that a 5% The rise in μ had a more detrimental effect on HT than the
concentration of CuO nanoparticles yields a maximum increase in kt in the study by Zheng et al.,237 However, Raei et
reduction in thermal resistance of 4.31% at 50 W. In contrast, al.238 found that the surge in μ had a lesser adverse impact on
the same concentration of alumina nanoparticles results in a HT than the rise in thermal conductivity. Additionally, the
more significant reduction of 6.66% under the same heat load, particle sizes of Al2O3 nanoparticles used by Zheng et al.237
with the highest convective heat transfer coefficient for the and Raei et al.238 were 50 and 20 nm, respectively. Smaller
heat pipe’s evaporator (437.91 W/m2K) achieved using Al2O3 nanoparticles were more susceptible to temperature changes,
nanofluid with a 1% nanoparticle concentration at 50 W. with increased Brownian motion at higher temperatures.
Further, Naruka et al.232 studied the performance of Al2O3-DI Combining Al2O3 nanofluids with TiO2 nanoparticles at a
water in HP for a prolonged time of 6−12 months with vf of 1:1 mass ratio resulted in Al2O3+TiO2 in water nanofluids
0.1−0.8 vol % of NP tested under varying heat loads of 10−60 (Singh and Sarkar).239 When the inlet temperature was 50 °C,

Table 8. Thermal Performance in a Plate HX with Nanofluids as the Working Fluid

MHTE
authors nanofluids (%) remarks
Zheng et al.242 Al2O3−water 19.8 0.05 wt% Fe3O4−water showed the optimal HT performance; empirical formulas of four nanofluids were
summarized
SiC−water 17.2
CuO−water 13.8
Fe3O4−water 21.9
Kumar et al.243 TiO2−water 9.09 MWCNT nanofluid showed the optimal HT performance; the optimum spacing of plate HX was 5 mm
Al2O3−water 16.81
ZnO−water 19.28
CeO2−water 23.41
Cu + Al2O3−water 37.11
water 45.45
GnP−water 52.86
MWCNT−water
Wang et al.244 GnP−EGW 4 The correlations of hm and f of the nanofluids in MPHE were summarized
Tiwari et al.245 CeO2−water 35.9 0.75 vol% CeO2−water nanofluids had an optimal performance index up to 16%
Al2O3−water 26.3
TiO2−water 24.1
SiO2−water 13.9
Bhattad and Al2O3−water 17.1 performance of hybrid nanofluids was higher than that of single-nanoparticle nanofluids
Sarkar246
Al2O3 + MWCNTs 25.36
(4:1)−water the increase in Δp was negligible

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the Nu of Al2O3+TiO2 in water nanofluids was 38.5% higher the potential of nanofluids in reducing environmental harm
than at 70 °C.239 This observed difference was attributed to and promoting sustainability.249−251
changes in the fluid’s ρ, μ, and thermal diffusivity with
temperature. Investigation of TiO2 nanofluids revealed that the 5. CONCLUSIONS AND RECOMMENDATIONS FOR
hm of 0.2% TiO2 in water was highest at 15 °C.240 The hm of FUTURE WORK
TiO2 nanofluids decreased as temperature increased. Fur- This study discusses the latest advancements in the develop-
thermore, CNT nanofluids exhibited higher Nu at 70 °C ment, stability, heat properties, and effectiveness of nanofluids
compared to 50 °C due to improved thermal properties and in thermal systems. Upon reviewing the literature, several key
enhanced Brownian motion and thermal diffusion abilities at findings were made regarding the recent progress of nanofluid
higher temperatures. In another study, the hm of 0.3 wt % MgO technology.
in ethylene glycol (EG) nanofluids was 9% higher at 60 °C Researchers have noted that incorporating nanoparticles into
than at 25 °C.230 Arya et al.241 noted changes in thermal base fluids can enhance thermal characteristics such as hm, kp,
conductivity, Cp, and μ of MgO in EG nanofluids between 25 μ, and ρ, impacting parameters like f, Re, Nu, and pump
and 100 °C. Thermal conductivity increased with temperature efficiency. Nanofluids are utilized in different applications
while viscosity decreased, explaining the improved HT based on their properties, and optimal conditions of temper-
performance at higher temperatures. A higher inlet temper- ature, φ, and particle size exist for improved THP. Using
ature enhanced the HT performance of fluids containing MgO nanofluids with greater heat capacity than the base fluid
and CNTs, while TiO2 nanofluids performed better at lower enhances thermal system efficiency. Thus, nanoparticles that
inlet temperatures. Further research is needed to investigate enhance heat capacity and kp of the base fluid should be
the impact of thermal conductivity and viscosity on fluid utilized for enhanced HT.
behavior. Stability is a crucial factor for nanofluids, with pH variation
playing a significant role in enhancing the stability and kp of
4. ENVIRONMENTAL IMPACT OF NANOFLUIDS nanofluids. Higher pumping power is required to counteract
Microscopic liquid suspensions containing tiny particles in the the effects of nanoparticle size and shape on Δp, stability
main fluid are known as nanofluids. Consequently, the overall analysis, rheological properties, and HT augmentation.
environmental influence of nanofluids is a blend of the Thermohydraulic properties play a crucial role in assessing
environmental impression of the main fluid and the nano- and augmenting the performance of nanofluids, with factors
particles. H2O is widely favored as the main fluid due to its like solid particle φ, Re, Δp, mf, regime, magnetic field, f, and
nontoxic, nonflammable, safe, and easy-to-use properties. The type of thermal device affecting the improvement of THP.
nature of the nanoparticles, their physical, chemical, toxic, and Additionally, thermodynamic performance is vital in design-
ecological effects, plays a crucial role in determining the ing HT systems, with entropy generation and exergy efficiency
environmental footprint of nanofluids. Additionally, the vf being essential factors reliant on the type of nanoparticle,
nanoparticles influences the environmental consequence of thermal application, type of flow regime, and φ. Increasing
nanofluids.247 Effective management of the environmental thermal efficiency reduces pressure, lowers system energy
effects of nanofluids relies heavily on the optimal design of the consumption, and minimizes exergy destruction. Analysis of
nanofluid. Utilizing natural substances like silica, alumina, and entropy generation is necessary to determine beneficial models
iron oxides outcomes in considerably lower environmental for thermal systems.
influences compared to the synthetic manufacturing of such Replacing conventional working fluids with nanofluids offers
particles. This approach helps minimize energy and material advantages in HT performance, though it may lead to
requirements for production. Furthermore, employing natural increased Δp, pumping power, and consequently high energy
nanoparticles, typically nontoxic variants, can further mitigate consumption, incurring additional costs. Limited studies exist
potential toxicity concerns during the application and disposal on the thermo-economic performance of nanofluids, neces-
of nanofluids. Similarly, reducing the concentration of sitating further research to analyze and optimize the cost
nanoparticles can mitigate potential environmental harm. performance of nanofluids for enhanced thermal applications.
The manner in which nanofluids are prepared significantly The enhanced kt and reduced viscosity of nanofluids make
influences their environmental impact. For instance, Barberio them promising for high-temperature applications, allowing for
and colleagues248 assessed the environmental impact of HT area expansion and potential size and weight reduction in
alumina nanofluids created using either a one-step or two- thermal systems. Nanofluids could have diverse applications in
step method. Their findings, based on a combined life cycle space exploration, aircraft engineering, and defense technology
assessment and risk assessment, indicated that the one-step industries.
method had nearly three times the environmental impact The form of additives profoundly influences the properties
compared to the two-step approach. The use of nanofluids to of nanofluids. Investigating innovative approaches to synthesiz-
improve HT processes offers environmental advantages by ing nanofluids for precise control over microscopic structures
enhancing energy efficiency, thereby reducing energy con- opens up intriguing avenues for research.
sumption, heat losses, and heat dissipation. Nanofluids The stability of suspensions holds paramount importance in
contribute to environmental and economic savings by lowering both theoretical investigations and practical implementations.
greenhouse gas emissions. Nanofluids can increase CO2 This encompasses enduring stability throughout extended
absorption, which helps reduce the environmental impact of durations and thermal cycles, necessitating heightened
carbon emissions that contribute to climate change and air scrutiny.
pollution. Various studies have demonstrated the positive The thermal performance of nanofluids at elevated temper-
environmental impact of nanofluids, such as reducing CO2 atures remains relatively uncharted territory, presenting
emissions from solar water heaters by using CeO2/water promising prospects for applications in high-temperature
nanofluids or copper nanoparticles. These examples highlight settings such as solar energy absorption and storage. However,
32341 https://doi.org/10.1021/acsomega.4c03279
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ACS Omega http://pubs.acs.org/journal/acsodf Review

the rise in temperatures could trigger surfactant deterioration MNCNT Multiwalled CNT
and heightened foam generation, demanding thorough STHX Shell and tube heat exchanger
consideration. TPF Thermal performance factor
Nanofluid research can be enriched and broadened by THP Thermal hydraulic performance
delving into innovative nanomaterials. U Overall heat transfer coefficient
FED Flow energy dissipation
■ AUTHOR INFORMATION
Corresponding Authors
HX
CNT
Heat exchanger
Carbon nanotube
S. M. Mozammil Hasnain − Faculty of Engineering and Cn Specific heat
Applied Science, Usha Martin University, Ranchi 835103, DBP Deflector baffle plate
India; Present Address: Marwadi University Research Nu Nusselt number
Centre, Department of Mechanical Engineering, Faculty PR Pitch ratio
of Engineering & Technology, Marwadi University, DPHE Double pipe HX
Rajkot, 360003, Gujrat, India; orcid.org/0000-0002- Pr Prandtl number
9340-1836; Email: smmh429@gmail.com PI Perforation index
Shatrudhan Pandey − Department of Production and DR Depth of wing cut ratios
Industrial Engineering, Birla Institute of Technology, Mesra, TT Typical twisted tape
Ranchi 835215, India; orcid.org/0000-0002-1400-8703; VG Vortex generator
Email: er.shatrudhanp@gmail.com HP Heat pipes
Anipa Tapalova − Department of Biology, Geography and nm Nanometer
Chemistry, Korkyt Ata Kyzylorda University, Kyzylorda
120014, Kazakhstan; Email: anipa52@mail.ru
Authors
■
ρ
GREEK LETTERS
Density (kg m−3)
Md Atiqur Rahman − Department of Mechanical Engineering, μ Coefficient of dynamic viscosity (kg·m−1 s−1)
Birla Institute of Technology, Mesra, Ranchi 835215, India; β Perforation ratio
Department of Mechanical Engineering, Vignan’s Foundation ϕ Concentration
for Science, Technology and Research (Deemed to be α Inclination angle
University), Vadlamudi, Guntur, Andhra Pradesh 522213, v Average velocity (m s−1)
India vf Volume fraction
Nurgali Akylbekov − Laboratory of Engineering Profile mf Mass fraction
“Physical and Chemical Methods of Analysis”, Korkyt Ata
Kyzylorda University, Kyzylorda 120014, Kazakhstan
Rustem Zairov − Aleksander Butlerov Institute of Chemistry,
Kazan Federal University, Kazan 420008, Russian
■ REFERENCES
(1) Mitchell, M. J.; Billingsley, M. M.; Haley, R. M.; Wechsler, M. E.;
Federation; A. E. Arbuzov Institute of Organic and Physical Peppas, N. A.; Langer, R. Engineering precision nanoparticles for drug
Chemistry, Kazan Scientific Center, Russian Academy of delivery. Nat. Rev. Drug Discovery 2021, 20 (2), 101−124.
Sciences, 420088 Kazan, Russian Federation; orcid.org/ (2) Lin, W. Introduction: Nanoparticles in Medicine. Chem. Rev.
2015, 115 (19), 10407−10409.
0000-0002-1699-6741
(3) Bannow, J.; Benjamins, J.; Wohlert, J.; Löbmann, K.; Svagan, A.
Complete contact information is available at: Solid nano foams based on cellulose nanofibers and indomethacin -
https://pubs.acs.org/10.1021/acsomega.4c03279 the effect of processing parameters and drug content on material
structure. Int. J. Pharm. 2017, 526 (1−2), 291−299.
Notes (4) Alemi, F. M.; Dehghani, S. A. M.; Rashidi, A.; Hosseinpour, N.;
The authors declare no competing financial interest. Mohammadi, S. Potential Application of Fe2O3 and Functionalized
SiO2 Nanoparticles for Inhibiting Asphaltene Precipitation in Live Oil

■ ACKNOWLEDGMENTS
This research was funded by a grant from the Ministry of
at Reservoir Conditions. Energy Fuels 2021, 35 (7), 5908−5924. 2021
(5) Afifi, H. R.; Mohammadi, S.; Mirzaei Derazi, A.; Mahmoudi
Alemi, F. Enhancement of smart water-based foam characteristics by
Science and Higher Education of the Russian Federation for SiO2 nanoparticles for EOR applications. Colloids Surf., A 2021, 627,
large scientific projects in priority areas of scientific and No. 127143.
technological development (075-15-2024-646). (6) Das, S. K.; Choi, S. U. S.; Patel, H. E. Heat Transfer Engineering
2006, 27 (10), 3−19.

■
f
NOMENCLATURE
Friction factor
(7) Zhang, Y.; Hangi, M.; Wang, X.; Rahbari, A. A comparative
evaluation of double-pipe heat exchangers with enhanced mixing.
Applied Thermal Engineering 2023, 230, No. 120793.
hm Convective heat transfer coefficient (W m2 K−1) (8) Babu, M. A.; Mohinoddin, M.; Sanke, N. Enhancing Efficiency of
HT Heat transfer Double Pipe Heat Exchangers with Nanofluids: A Comprehensive
Kp Thermal conductivity, W m−1 K−1 Review of Strategies. International Journal Of Engineering Research &
Technology 2023, 12, 07 DOI: 10.17577/IJERTV12IS070086.
Δp Pressure drop in HX, (Pa) (9) Alshukri, M. J.; Kadhim Hussein, A.; Eidan, A. A.; Alsabery, A. I.
Re Reynolds number A review on applications and techniques of improving the
PEC Performance evaluation criteria performance of heat pipe-solar collector systems. Sol. Energy 2022,
CBP Conical baffle plate 236, 417−433.
TEF Thermal enhancement factor (10) Bhanvase, B.; Barai, D. Thermophysical properties of
MHS Miniature heat sinks nanofluids. Nanofluids for Heat and Mass Transfer 2021, 101−166.

32342 https://doi.org/10.1021/acsomega.4c03279
ACS Omega 2024, 9, 32328−32349
ACS Omega http://pubs.acs.org/journal/acsodf Review

(11) Wang, X.; Xu, X.; Choi, S. U. S. Thermal Conductivity of (30) Choi, S. U. S.; Zhang, Z. G.; Yu, W.; Lockwood, F. E.; Grulke,
Nanoparticle - Fluid Mixture. Journal of Thermophysics and Heat E. A. Anomalous thermal conductivity enhancement in nanotube
Transfer 1999, 13 (4), 474−480. suspensions. Appl. Phys. Lett. 2001, 79, 2252−4.
(12) Dehkordi, B. A. F.; Abdollahi, A. Experimental investigation (31) Wessel, D. ASHRAE Fundamentals Handbook; American
toward obtaining the effect of interfacial solid-liquid interaction and Society of Heating, Refrigerating, and Air-Conditioning Engineers:
basefluid type on the thermal conductivity of CuO-loaded nanofluids. Atlanta, GA, USA, 2001.
International Communications in Heat and Mass Transfer 2018, 97, (32) Balandin, A. A. Thermal properties of graphene and
151−162. nanostructured carbon materials. Nat. Mater. 2011, 10, 569−81.
(13) Chikkatti, B. S.; Sajjan, A. M.; Banapurmath, N. R. Facilitating (33) Syam Sundar, L.; Venkata Ramana, E.; Singh, M. K.; Sousa, A.
Ionic Conduction in the Valve-Regulated Lead Acid Battery by C. M. Thermal conductivity and viscosity of stabilized ethylene glycol
Poly(vinyl alcohol)-Halloysite Nano-Clay Gel Polymer Electrolyte. and water mixture Al2O3 nanofluids for heat transfer applications: an
Energy Technology 2024, 12 (5), No. 2301265. experimental study. Int. Commun. Heat Mass Trans. 2014, 56, 86−95.
(14) Chikkatti, B. S.; Sajjan, A. M.; Kalahal, P. B.; Banapurmath, N. (34) Khetib, Y.; Alahmadi, A.; Alzaed, A.; Sharifpur, M.; Cheraghian,
R.; Angadi, A. R. Insight into the performance of VRLA battery using G.; Siakachoma, C. Simulation of a Parabolic Trough Solar Collector
PVA-TEOS hybrid gel electrolytes with titania nanoparticles. Journal Containing Hybrid Nanofluid and Equipped with Compound
of Energy Storage 2023, 72, No. 108572. Turbulator to Evaluate Exergy Efficacy and Thermal-Hydraulic
(15) Chikkatti, B. S.; Sajjan, A. M.; Banapurmath, N. R.; Bhutto, J. Performance. Energy Sci. Eng. 2022, 10, 4304−4317.
K.; Verma, R.; Yunus Khan, T. M. Fabrication of Flexible Films for (35) Akhtar, N.; Rani, M.; Mahmood, A.; Saba, H.; Khan, S.;
Supercapacitors Using Halloysite Nano-Clay Incorporated Poly(lactic Murtaza, G.; Hegazy, H.; AlObaid, A.; Al-Muhimeed, T. I.; Ali, S.
acid). Polymers 2023, 15 (23), 4587. Synthesis and characterization of MXene/BiCr2O4 nanocomposite
(16) Sun, W.; Xiao, T.; Liu, Q.; Zhao, J.; Liu, C. Experimental study with excellent electrochemical properties. J. Mater. Res. Technol. 2021,
on glycerol/aldehyde or ketone binary nanofluids for thermal 15, 2007−2015.
management. Int. J. Heat Mass Transfer 2023, 214, No. 124463. (36) Sheikholeslami, M. Numerical investigation of solar system
(17) Al-Hasani, H. M.; Freegah, B. Influence of secondary flow angle equipped with innovative turbulator and hybrid nanofluid, Sol. Energy
and pin fin on hydro-thermal evaluation of double outlet serpentine Mater. Sol. Cells 2022, 243, No. 111786.
mini-channel heat sink. Results Eng. 2022, 16, No. 100670. (37) Selimefendigil, F.; Oztop, H. F.; Doranehgard, M. H.; Karimi,
(18) Sun, W.; Liu, Q.; Zhao, J.; Muhammad Ali, H.; Said, Z.; Liu, C. N. Phase change dynamics in a cylinder containing hybrid nanofluid
Experimental study on sodium acetate trihydrate/glycerol deep and phase change material subjected to a rotating inner disk. J. Energy
eutectic solvent nanofluids for thermal energy storage. J. Mol. Liq. Storage 2021, 42, 103007.
2023, 372, No. 121164. (38) AbdRabbuh, O. A.; Abdelrazek, A. H.; Kazi, S. N.; Zubir, M. N.
(19) Geng, L.; Wang, J.; Yang, X.; Jiang, J.; Li, R.; Yan, Y.; Zhao, J.;
M. Nanofluids thermal performance in the horizontal annular
Liu, C. Synergistic enhancement of phase change materials through
passages: a recent comprehensive review. J. Therm. Anal. Calorim.
three-dimensional porous layered covalent triazine framework/
2022, 147, No. 11633.
expanded graphite composites for solar energy storage and beyond.
(39) Younes, H.; Christensen, G.; Li, D.; Hong, H.; Ghaferi, A. A.
Chemical Engineering Journal 2024, 487, No. 150749.
Thermal Conductivity of Nanofluids: Review. Journal of Nanofluids
(20) Xiao, T.; Shi, X.; Gen, L.; Dai, Y.; Zhao, J.; Liu, C. Synergistic
2015, 4 (2), 107−132.
enhancement of phase change materials through three-dimensional
(40) Maxwell, J. C. A Treatise on Electricity and Magnetism, 2nd ed.;
macropore lamellar structured MOF/EG composite for solar energy
Clarendon Press: Oxford, UK, 1981.
storage and beyond. Applied Thermal Engineering 2023, 235,
(41) Pak, B. C.; Cho, Y. I. Hydrodynamic and heat transfer study of
No. 121378.
(21) Almatar AbdRabbuh, O.; Oon, C. S.; Kazi, S. N.; Abdelrazek, A. dispersed fluids with submicron metallic oxide particles. Exp. Heat
H.; Ahmed, W.; Mallah, A. R.; Badarudin, A.; Badruddin, I. A.; Transfer 1998, 11, No. 151.
Kamangar, S. An experimental investigation of eco-friendly treated (42) Batchelor, G. The effect of Brownian motion on the bulk stress
GNP heat transfer growth: circular and square conduit comparison. J. in a suspension of spherical particles. J. Fluid Mech. 1977, 83, No. 97.
Therm. Anal. Calorim. 2021, 145 (1), 139−151. (43) Buongiorno, J. Convective Transport in Nanofluids, ASME. J.
(22) Perry, R. H., Green, D. W. Perry’s Chemical Engineers’ Heat Transfer. 2006, 128 (3), 240−250.
Handbook, 7th ed.; McGraw-Hill Inc.: New York, NY, U.S.A., 1997. (44) Suresh, S.; Venkitaraj, K.; Selvakumar, P.; Chandrasekar, M.
(23) Alghoul, M. A.; Sulaiman, M. Y.; Azmi, B. Z.; Wahab, M. A. Effect of Al2O3− Cu/ water hybrid nanofluid in heat transfer. Exp
Review of materials for solar thermal collectors. Anti Corros Methods Therm Fluid Sci. 2012, 38, 54−60.
Mater. 2005, 52, 199−206. (45) Esfe, M. H.; Afrand, M.; Rostamian, S. H.; Toghraie, D.
(24) Shackelford, J. F., Alexande, R W. CRC Materials Science and Examination of rheological behavior of MWCNTs/ZnO-SAE40
Engineering Handbook, 3rd ed.; CRC Press: Boca Raton, FL, USA, hybrid nanolubricants under various temperatures and solid volume
2001. DOI: 10.1201/9781420038408. fractions. Exp Therm Fluid Sci. 2017, 80, 384−90.
(25) Xuan, Y.; Li, Q.; Zhang, X.; Fujii, M. Stochastic thermal (46) Esfe, M. H.; Wongwises, S.; Naderi, A.; Asadi, A.; Safaei, M. R.;
transport of nanoparticle suspensions. J. Appl. Phys. 2006, 100, Rostamian, H.; Dahari, M.; Karimipour, A. Thermal conductivity of
No. 043507. Cu/TiO2−water/EG hybrid nanofluid: experimental data and
(26) Hwang, Y.; Lee, J. K.; Lee, C. H.; Jung, Y. M.; Cheong, S. I.; modeling using artificial neural network and correlation. Int. Commun.
Lee, C. G.; Ku, B. C.; Jang, S. P. Stability and thermal conductivity Heat Mass Trans. 2015, 66, 100−4.
characteristics of nanofluids. Thermochim. Acta 2007, 455, 70−4. (47) Abbasi, S. M.; Rashidi, A.; Nemati, A.; Arzani, K. The effect of
(27) Kim, S. H.; Choi, S. R.; Kim, D. Thermal conductivity of metal- functionalisation method on the stability and the thermal con-
oxide nanofluids: particle size dependence and effect of laser ductivityof nanofluid hybrids of carbon nanotubes/gamma alumina.
irradiation. J. Heat Transf Trans. 2007, 129, 298−307. Ceram. Int. 2013, 39, 3885−91.
(28) Vajjha, R. S.; Das, D. K.; Kulkarni, D. P. Development of new (48) Afrand, M. Experimental study on thermal conductivity of
correlations for convective heat transfer and friction factor in ethylene glycol containing hybrid nano-additives and development of
turbulent regime for nanofluids. Int. J. Heat Mass Transfer 2010, 53, a new correlation. Appl. Therm Eng. 2017, 110, 1111−9.
4607−18. (49) Gürbüz, E. Y.; Variyenli, HI;̇ Sözen, A.; Khanlari, A.; Ö kten, M.
(29) Syam Sundar, L.; Singh, M. K. Convective heat transfer and Experimental and numerical analysis on using CuO-Al2O3/water
friction factor correlations of nanofluid in a tube and with inserts: a hybrid nanofluid in a U-type tubular heat exchanger. Int. J. Numer
review. Renew Sustain Energy Rev. 2013, 20, 23−35. Method H. 2021, 31 (1), 519−540.

32343 https://doi.org/10.1021/acsomega.4c03279
ACS Omega 2024, 9, 32328−32349
ACS Omega http://pubs.acs.org/journal/acsodf Review

(50) Ahammed, N.; Asirvatham, L. G.; Wongwises, S. Entropy (68) Giwa, S. O.; Momin, M.; Nwaokocha, C. N.; Sharifpur, M.;
generation analysis of graphene−alumina hybrid nanofluid in Meyer, J. P. Influence of nanoparticles size, percent mass ratio, and
multiport minichannel heat exchanger coupled with thermoelectric temperature on the thermal properties of water-based MgO−ZnO
cooler. Int. J. Heat Mass Transfer 2016, 103, 1084−97. nanofluid: an experimental approach. J. Therm Anal Calorim. 2021,
(51) Chen, L.; Yu, W.; Xie, H. Enhanced thermal conductivity of 143, 1063−1079.
nanofluids containing Ag/MWNT composites. Powder Technol. 2012, (69) Chakraborty, S. An Investigation on the Long-Term Stability of
231, 18−20. TiO2 Nanofluid. Mater. Today Proc. 2019, 11, 714−718.
(52) Esfe, M. H.; Arani, A. A. A.; Rezaie, M.; Yan, W. M.; (70) Zhu, H. T.; Lin, Y. S.; Yin, Y. S. A Novel One-step Chemical
Karimipour, A. Experimental determination of thermal conductivity Method for Preparation of Copper Nanofluids. J. Colloid Interface Sci.
and dynamic viscosity of Ag−MgO/ water hybrid nanofluid. Int. 2004, 277, 100−103.
Commun. Heat Mass Transfer 2015, 66, 189−95. (71) Kumar, S. A.; Meenakshi, K. S.; Narashimhan, B. R. V.;
(53) Chopkar, M.; Kumar, S.; Bhandari, D.; Das, P. K.; Manna, I. Srikanth, S.; Arthanareeswaran, G. Synthesis and Characterization of
Development and characterization of Al2Cu and Ag2Al nanoparticle Copper Nanofluid by a Novel One-step Method. Mater. Chem. Phys.
dispersed water and ethylene glycol based nanofluid. Mater. Sci. Eng: 2009, 113, 57−62.
B 2007, 139, 141−8. (72) Wang, J.; Li, G.; Zhu, H.; Luo, J.; Sundén, B. Experimental
(54) Martin, K.; Sözen, A.; Ç iftçi, E.; Ali, H. M. An experimental Investigation on Convective Heat Transfer of Ferrofluids inside a Pipe
investigation on aqueous Fe−CuO hybrid nanofluid usage in a plain under VariousMagnet Orientations. Int. J. Heat Mass Transfer 2019,
heat pipe. Int. J. Thermophys. 2020, 41, 135. 132, 407−419.
(55) Minea, A. A. Hybrid nanofluids based on Al2O3, TiO2 and (73) Wang, J.; Li, G.; Li, T.; Zeng, M.; Sundén, B. Effect of Various
SiO2: numerical evaluation of different approaches. Int. J. Heat Mass Surfactants on Stability and Thermophysical Properties of Nanofluids.
Transfer 2017, 104, 852−60. J. Therm. Anal. Calorim. 2021, 143, 4057−4070.
(56) Asadi, M.; Asadi, A. Dynamic viscosity of MWCNT/ZnO− (74) Zheng, D.; Yang, J.; Wang, J.; Kabelac, S.; Sundén, B. Analyses
engine oil hybrid nanofluid: an experimental investigation and new of thermal Performance and Pressure Drop in a Plate Heat Exchanger
correlation in different temperatures and solid concentrations. Int. Filled with Ferrofluids under a Magnetic Field. Fuel 2021, 293,
Commun. Heat Mass Trans. 2016, 76, 41−5. 120432−120525.
(57) Gürbüz, E. A.; Sözen, A.; Keçebaş, A.; Ö zbaş, E. Experimental (75) Teng, T. P.; Cheng, C. M.; Pai, F. Y. Preparation and
and numerical investigation of diffusion absorption refrigeration characterization of carbon nanofluid by a plasma arc nanoparticles
system working with ZnOAl2O3 and TiO2 nanoparticles added synthesis system. Nanoscale Res. Lett. 2011, 6 (1), 1−11.
ammonia/water nanofluid. Exp Heat Transfer 2022, 35 (3), 197−222. (76) Kong, L.; Sun, J.; Bao, Y. Preparation, characterization and
(58) Nine, M. J.; Munkhbayar, B.; Rahman, M. S.; Chung, H.; Jeong, tribological mechanism of nanofluids. Rsc Advances 2017, 7 (21),
H. Highly productive synthesis process of well dispersed Cu2O And 12599−12609.
(77) Li, Y.; Zhou, J.; Tung, S.; Schneider, E.; Xi, S. A review on
Cu/Cu2O nanoparticles and its thermal characterization. Mater.
development of nanofluid preparation and characterization. Powder
Chem. Phys. 2013, 141, 636−42.
Technol. 2009, 196 (2), 89−101.
(59) Jana, S.; Salehi-Khojin, A.; Zhong, W.-H. Enhancement of fluid
(78) Wang, X. Q.; Mujumdar, A. S. A review on nanofluids - Part II:
thermal conductivity by the addition of single and hybrid nano-
experiments and applications. Braz. J. Chem. Eng. 2008, 25 (4), 631−
additives. Thermochim. Acta 2007, 462, 45−55.
648.
(60) Baghbanzadeh, M.; Rashidi, A.; Rashtchian, D.; Lotfi, R.;
(79) Gadekar, R. A.; Thakur, K. K.; Kumbhare, S. ZnO a Nanofluid
Amrollahi, A. Synthesis of spherical silica/multiwall carbon nanotubes
in Radiator to Increase Thermal Conductivity Based on Ethylene
hybrid nanostructures and investigation of thermal conductivity of Glycol. International Journal Of Advance Research And Innovative Ideas
related nanofluids. Thermochim. Acta 2012, 549, 87−94. In Education. 2015, 4, 78−83.
(61) Paul, G.; Philip, J.; Raj, B.; Das, P. K.; Manna, I. Synthesis, (80) Etedali, S.; Afrand, M.; Abdollahi, A. Effect of different
characterization, and thermal property measurement of nano- surfactants on the pool boiling heat transfer of SiO2/deionized water
Al95Zn05 dispersed nanofluid pre-pared by a twostep process. Int. nanofluid on a copper surface. Int. J. Therm. Sci. 2019, 145,
J. Heat Mass Transfer 2011, 54, 3783−8. No. 105977.
(62) Munkhbayar, B.; Tanshen, M. R.; Jeoun, J.; Chung, H.; Jeong, (81) Kujawska, A.; Zajaczkowski, B.; Wilde, L. M.; Buschmann, M.
H. Surfactant- free dispersion of silver nanoparticles into MWCNTa- H. Geyser boiling in a thermosyphon with nanofluids and surfactant
queous nanofluids prepared by one-step technique and their thermal solution. Int. J. Therm. Sci. 2019, 139, 195−216.
characteristics. Ceram. Int. 2013, 39, 6415−25. (82) Abbasi, S. M.; Rashidi, A.; Nemati, A.; Arzani, K. The effect of
(63) Batmunkh, M.; Tanshen, M. R.; Nine, M. J.; Myekhlai, M.; functionalisation method on the stability and the thermal conductivity
Choi, H.; Chung, H.; Jeong, H. Thermal conductivity of TiO2 of nanofluid hybrids of carbon nanotubes/gamma alumina. Ceram.
nanoparticles based aqueous nanofluids with an addition of a Int. 2013, 39 (4), 3885−3891.
modified silver particle. Ind. Eng. Chem. Res. 2014, 53, 8445−51. (83) Ghozatloo, A.; Shariaty-Niasar, M.; Rashidi, A. M. Preparation
(64) Arani, A. A. A.; Pourmoghadam, F. Experimental investigation of nanofluids from functionalized Graphene by new alkaline method
of thermal conductivity behavior of MWCNTS-Al2O3/Ethylene glycol and study on the thermal conductivity and stability. Int. Commun.
hybrid nanofluid: providing new thermal conductivity correlation. Heat Mass Trans. 2013, 42, 89−94.
Heat Mass Transfer 2019, 55, 2329−39. (84) Iranidokht, V.; Hamian, S.; Mohammadi, N.; Shafii, M. B.
(65) Farajzadeh, E.; Movahed, S.; Hosseini, R. Experimental and Thermal conductivity of mixed nanofluids under controlled pH
numerical investigations on the effect of Al2O3/TiO2-H2O nanofluids conditions. Int. J. Therm. Sci. 2013, 74, 63−71.
on thermal efficiency of the flat plate solar collector. Renew Energy. (85) Mukherjee, S.; Chakrabarty, S.; Mishra, P. C.; Chaudhuri, P.
2018, 118, 122−30. Transient heat transfer characteristics and process intensification with
(66) Esfe, M. H.; Esfandeh, S.; Amiri, M. K.; Afrand, M. A novel Al2O3-water and TiO2-water nanofluids: an experimental inves-
applicable experimental study on the thermal behavior of SWCNTs tigation. Chem. Eng. Process. - Process Intensif. 2020, 150, No. 107887.
(60%)- MgO (40%)/EG hybrid nanofluid by focusing on the thermal (86) Mahbubul, I. M.; Elcioglu, E. B.; Amalina, M. A.; Saidur, R.
conductivity. Powder Technol. 2019, 342, 998−1007. Stability, thermophysical properties and performance assessment of
(67) Giwa, S. O.; Sharifpur, M.; Meyer, J. P.; Wongwises, S.; Mahian, alumina−water nanofluid with emphasis on ultrasonication and
O. Experimental measurement of viscosity and electrical conductivity storage period. Powder Technol. 2019, 345, 668−675.
of waterbased γ-Al2O3/MWCNT hybrid nanofluids. J. Therm Anal (87) Gulzar, O.; Qayoum, A.; Gupta, R. Experimental study on
Calorim. 2021, 143, 1037−1050. stability and rheological behaviour of hybrid Al2O3-TiO2 Therminol-

32344 https://doi.org/10.1021/acsomega.4c03279
ACS Omega 2024, 9, 32328−32349
ACS Omega http://pubs.acs.org/journal/acsodf Review

55 nanofluids for concentrating solar collectors. Powder Technol. hybrid nanofluid without surfactant. Microfluid Nanofluid 2021, 25,
2019, 352, 436−444. 14.
(88) Ho, M.; Oon, C.; Tan, L.; Wang, Y.; Hung, Y. A review on (108) Xian, H. W.; Sidik, N. O. C.; Saidur, R. Impact of different
nanofluids coupled with extended surfaces for heat transfer enhance- surfactants and ultrasonication time on the stability and thermophys-
ment. Results in Engineering 2023, 17, No. 100957. ical properties of hybrid nanofluids. Int. Commun. Heat Mass Trans.
(89) Arora, N.; Gupta, M. Thermo-hydraulic performance of 2020, 110, No. 104389.
nanofluids in enhanced tubes - a review. Heat Mass Transfer 2021, (109) Li, X.; Zhu, D.; Wang, X. Evaluation on dispersion behavior of
57 (3), 377−404. the aqueous copper nano-suspensions. J. Colloid Interface Sci. 2007,
(90) Bakthavatchalam, B.; Habib, K.; Saidur, R.; Saha, B. B.; Irshad, 310, 456−63.
K. Comprehensive study on nanofluid and ionanofluid for heat (110) Khairul, M. A.; Shah, K.; Doroodchi, E.; Azizian, R.;
transfer enhancement: a review on current and future perspective. J. Moghtaderi, B. Effects of surfactant on stability and thermo-physical
Mol. Liq. 2020, 305, No. 112787. properties of metal oxide nanofluids. Int. J. Heat Mass Transfer 2016,
(91) Chakraborty, S.; Panigrahi, P. K. Stability of nanofluid: a 98, 778−87.
review. Appl. Therm Eng. 2020, 174, No. 115259. (111) Cacua, K.; Ordonez, F.; Zapata, C.; Herrera, B.; Pabon, E.;
(92) Hong, H.; Wright, B.; Wensel, J.; Jin, S.; Ye, X. R.; Roy, W. Buitrago-Sierra, R. Surfactant concentration and pH effects on the
Enhanced thermal conductivity by the magnetic field in heat transfer zeta potential values of alumina nanofluids to inspect stability. Coll.
nanofluids containing carbon nanotube. Synth. Met. 2007, 157 (10), Surf. A Physicochem Eng. Asp. 2019, 583, No. 123960.
437−40. (112) Choudhary, R.; Khurana, D.; Kumar, A.; Subudhi, S. Stability
(93) Chang, Ho; Tsung, T. T.; Lin, C. R.; Lin, H. M.; Lin, C. K.; Lo, analysis of Al2O3/ water nanofluids. J. Exp Nanosci. 2017, 12, 140−51.
C. H.; Su, H. T. A study of magnetic field effect on nanofluid stability (113) Song, Y. Y.; Bhadeshia, H. K. D. H.; Suh, D. W. Stability of
of CuO. Mater. Trans. 2004, 45 (4), 1375−8. stainless-steel nanoparticle and water mixtures. Powder Technol. 2015,
(94) Zhang, T.; Zou, Q.; Cheng, Z.; Chen, Z.; Liu, Y.; Jiang, Z. 272, 34−44.
Effect of particle concentration on the stability of water-based SiO2 (114) Chakraborty, S.; Sengupta, I.; Sarkar, I.; Pal, S. K.;
nanofluid. Powder Technol. 2021, 379, 457−65. Chakraborty, S. Effect of surfactant on thermophysical properties
(95) Hutin, A.; Lima, N.; Lopez, F.; Carvalho, M. Stability of Silica and spray cooling heat transfer performance of Cu-Zn-Al LDH
Nanofluids at High Salinity and High Temperature. Powders 2023, 2 nanofluid. Appl. Clay Sci. 2019, 168, 43−55.
(1), 1−20. (115) Jiang, L.; Gao, L.; Sun, J. Production of aqueous colloidal
(96) Bushehri, M. K.; Mohebbi, A.; Rafsanjani, H. H. Prediction of dispersions of carbon nanotubes. J. Colloid Interface Sci. 2003, 260,
thermal conductivity and viscosity of nanofluids by molecular
89−94.
dynamics simulation. J. Eng. Thermophys. 2016, 25, 389−400. (116) Aydın, D. Y.; Gürü, M.; Sözen, A. Experimental investigation
(97) Hong, J.; Kim, D. Effects of aggregation on the thermal
on thermal performance of thermosyphon heat pipe using dolomite/
conductivity of alumina/water nanofluids. Thermochim. Acta 2012,
deionized water nanofluid depending on nanoparticle concentration
542, 28−32.
and surfactant type. Heat Transf Res. 2020, 51, 1073−85.
(98) Arthur, O.; Karim, M. A. An investigation into the
(117) Kim, H. J.; Bang, I. C.; Onoe, J. Characteristic stability of bare
thermophysical and rheological properties of nanofluids for solar
Au water nanofluids fabricated by pulsed laser ablation in liquids. Opt
thermal applications. Renew Sustain Energy Rev. 2016, 55, 739−55.
(99) Chakraborty, S.; Sarkar, I.; Ashok, A.; Sengupta, I.; Pal, S. K.; Lasers Eng. 2009, 47, 532−8.
(118) Mondragon, R.; Julia, J. E.; Barba, A.; Jarque, J. C.
Chakraborty, S. Thermophysical properties of Cu-Zn-Al LDH
nanofluid and its application in spray cooling. Appl. Therm Eng. Characterization of silica-water nanofluids dispersed with an ultra-
2018, 141, 339−51. sound probe: a study of their physical properties and stability. Powder
(100) Wang, X. J.; Zhu, D. S.; Yang, S. Investigation of pH and Technol. 2012, 224, 138−46.
SDBS on enhancement of thermal conductivity in nanofluids. Chem. (119) Chen, H. J.; Wen, D. Ultrasonic-aided fabrication of gold
Phys. Lett. 2009, 470, 107−11. nanofluids. Nanoscale Res. Lett. 2011, 6, 198.
(101) Sandhu, H. G.; Singh, D. M. Experimental study on stability of (120) Mahbubul, I. M.; Elcioglu, E. B.; Saidur, R.; Amalina, M. A.
different nanofluids by using different nanoparticles and basefluids. Optimization of ultrasonication period for better dispersion and
4th Thermal and Fluids Engineering Conference, Las Vegas, NV, April stability of TiO2−water nanofluid. Ultrason Sonochem. 2017, 37, 360−
14−17, 2019,ASTFE, 2019; p 27991. DOI: 10.1615/TFEC2019.e- 7.
pa.027991. (121) Azmi, W. H.; Hamid, K. A.; Mamat, R.; Sharma, K. V.;
(102) Ahammed, N.; Asirvatham, L. G.; Wongwises, S. Effect of Mohamad, M. Effects of working temperature on thermo-physical
volume concentration and temperature on viscosity and surface properties and forced convection heat transfer of TiO2 nanofluids in
tension of graphene−water nanofluid for heat transfer applications. J. water−ethylene glycol mixture. Appl. Therm Eng. 2016, 106, 1190−9.
Therm Anal Calorim. 2016, 123, 1399−409. (122) Mahbubul, I. M.; Saidur, R.; Amalina, M. A.; Niza, M. E.
(103) Srinivas, V.; Moorthy, C.. V. Ch. V. K. N. S. N.; Dedeepya, V.; Influence of ultrasonication duration on rheological properties of
Manikanta, P. V.; Satish, V. Nanofluids with CNTs for automotive nanofluid: an experimental study with alumina−water nanofluid. Int.
applications. Heat Mass Transfer 2016, 52, 701−12. Commun. Heat Mass Transfer 2016, 76, 33−40.
(104) Hwang, Y.; Lee, J.-K.; Lee, J.-K.; Jeong, Y.-M.; Cheong, S.-i.; (123) Mahbubul, I.; Saidur, R.; Amalina, M.; Elcioglu, E.; Okutucu-
Ahn, Y.-C.; Kim, S. H. Production and dispersion stability of Ozyurt, T. Effective ultrasonication process for better colloidal
nanoparticles in nanofluids. Powder Technol. 2008, 186, 145−53. dispersion of nanofluid. Ultrasonics Sonochemistry 2015, 26, 361−369.
(105) Mostafizur, R. M.; Aziz, A. R. A.; Saidur, R.; Bhuiyan, M. H. (124) Wamkam, C. T.; Opoku, M. K.; Hong, H.; Smith, P. Effects of
U. Investigation on stability and viscosity of SiO2− CH3OH pH on heat transfer nanofluids containing ZrO 2 and TiO 2
(methanol) nanofluids. Int Commun. Heat Mass Trans. 2016, 72, nanoparticles. J. Appl. Phys. 2011, 109 (2), na.
16−22. (125) Zhang, H.; Qing, S.; Zhai, Y.; Zhang, X.; Zhang, A. The
(106) Ghadimi, A.; Metselaar, I. H. The influence of surfactant and changes induced by pH in TiO2/water nanofluids: stability,
ultrasonic processing on improvement of stability, thermal con- thermophysical properties and thermal performance. Powder Technol.
ductivity and viscosity of Titania nanofluid. Exp Therm Fluid Sci. 2021, 377, 748−59.
2013, 51, 1−9. (126) Wang, X. J.; Zhu, D. S.; Yang, S. Investigation of pH and
(107) Gupta, N.; Gupta, S. M.; Sharma, S. K. Synthesis, SDBS on enhancement of thermal conductivity in nanofluids. Chem.
characterization and dispersion stability of water-based Cu−CNT Phys. Lett. 2009, 470, 107−111.

32345 https://doi.org/10.1021/acsomega.4c03279
ACS Omega 2024, 9, 32328−32349
ACS Omega http://pubs.acs.org/journal/acsodf Review

(127) Zhu, D.; Li, X.; Wang, N.; Wang, X.; Gao, J.; Li, H. Dispersion performance of Nanofluid: a state-of- the-art review. Int. J.
behavior and thermal conductivity characteristics of Al2O3−H2O Thermofluid. 2021, 9, No. 100065.
nanofluids. Curr. Appl. Phys. 2009, 9, 131−139. (148) Iqbal, M.; Kouloulias, K.; Sergis, A.; Hardalupas, Y. Critical
(128) Said, Z.; Saidur, R.; Sabiha, M. A.; Hepbasli, A.; Rahim, N. A. analysis of thermal conductivity enhancement of alumina−water
Energy and exergy efficiency of a flat plate solar collector using pH nanofluids. J. Therm Anal Calorim 2023, 148, 9361−9389.
treated Al2O3 nanofluid. J. Clean. Prod. 2016, 112, 3915. (149) Tiecher, R. F.; Parise, J. A. A comparative parametric study on
(129) Maxwell, J. C. A. Treatise on Electricity and Magnetism; Oxford single-phase Al2O3- water nanofluid exchanging heat with a phase-
University Press: Cambridge, 1904. changing fluid. Int. J. Therm Sci. 2013, 74, 190−8.
(130) Hamilton, R. L.; Crosser, O. K. Thermal conductivity of (150) Goodarzi, M.; Kherbeet, A. S.; Afrand, M.; Sadeghinezhad, E.;
heterogeneous two component systems. Ind. Eng. Chem. Fundam Mehrali, M.; Zahedi, P.; Wongwises, S.; Dahari, M. Investigation of
1962, 1, 187−91. heat transfer performance and friction factor of a counter-flow double-
(131) Bruggeman, D. A. G. Berechnung verschiedener physikalischer pipe heat exchanger using nitrogen-doped, graphenebased nanofluids.
konstanten von heterogenen Substanzen, I. Dielektrizitätskonstanten Int. Commun. Heat Mass Transfer. 2016, 76, 16−23.
und Leitfähigkeiten der Mischkorper aus Isotropen Substanzen. Ann. (151) Akhavan-Behabadi, M.; Shahidi, M.; Aligoodarz, M. R.;
Phys. (Leipz) 1935, 416, 636−79. Fakoor- Pakdaman, M. An experimental investigation on rheological
(132) Patel, H. E.; Sundararajan, T.; Pradeep, T.; Dasgupta, A.; properties and heat transfer performance of MWCNTwater nanofluid
Dasgupta, N.; Das, S. K. A micro-convection model for thermal flow inside vertical tubes. Appl. Therm Eng. 2016, 106, 916−24.
conductivity of nanofluids. Pramana J. Phys. 2005, 65, 863−9. (152) Ezekwem, C.; Dare, A. Thermal and electrical conductivity of
(133) Rea, U.; McKrell, T.; Hu, L.; Buongiorno, J. Laminar silicon carbide nanofluids. Energy Sources A Recovery Util Environ. Eff.
convective heat transfer and viscous pressure loss of alumina−water 2020, 1−19.
and zirconia−water nanofluids. Int. J. Heat Mass Transf 2009, 52 (7), (153) Suresh, S.; Venkitaraj, K. P.; Selvakumar, P.; Chandrasekar, M.
2042−2048. Synthesis of Al2O3- Cu/water hybrid nanofluids using two step
(134) Eastman, J. A.; Phillpot, S. R.; Choi, S. U. S.; Keblinski, P. method and its thermo physical properties. Coll Surf. A Physicochem
Thermal transport in nanofluids. Ann. Rev. Mater. Res. 2004, 34, 219− Eng. Asp. 2011, 388, 41−8.
246. (154) Akhavan-Zanjani, H.; Saffar-Avval, M.; Mansourkiaei, M.;
(135) Evans, W.; Prasher, R.; Fish, J.; Meakin, P.; Phelan, P.; Sharif, F.; Ahadi, M. Experimental investigation of laminar forced
Keblinski, P. Effect of aggregation and interfacial thermal resistance convective heat transfer of Graphene−water nanofluid inside a
on thermal conductivity of nanocomposites and colloidal nanofluids. circular tube. Int. J. Therm. Sci. 2016, 100, 316−323.
Int. J. Heat Mass Transfer 2008, 51, 1431−8. (155) Kiyomura, I.S.; Manetti, L.L.; da Cunha, A.P.; Ribatski, G.;
(136) Singh, P. K.; Anoop, K. B.; Sundararajan, T.; Das, S. K. Cardoso, E.M. An analysis of the effects of nanoparticles deposition
on characteristics of the heating surface and ON pool boiling of water.
Entropy generation due to flow and heat transfer in nanofluids. Int. J.
Int. J. Heat Mass Transfer 2017, 106, 666−674.
Heat Mass Transf 2010, 53, 4757−67.
(156) Garbadeen, I.; Sharifpur, M.; Slabber, J.; Meyer, J.
(137) Khanafer, K.; Vafai, K. A critical synthesis of thermophysical
Experimental study on natural convection of MWCNT-water
characteristics of nanofluids. Int. J. Heat Mass Transfer 2011, 54,
nanofluids in a square enclosure. Int. Commun. Heat Mass Transfer
4410−28.
2017, 88, 1−8.
(138) Lu, S. Y.; Lin, H. C. Effective conductivity of composites
(157) Reza, J.; Mebarek-Oudina, F.; Makinde, O. D. MHD Slip Flow
containing aligned spheroidal inclusions of finite conductivity. J. Appl.
of Cu-Kerosene Nanofluid in a Channel with Stretching Walls Using
Phys. 1996, 79 (9), 6761. 3-Stage Lobatto IIIA Formula. Defect and Diffusion Forum 2018, 387,
(139) Wang, W.; Lin, L.; Feng, Z. X.; Wang, S. Y. A comprehensive
51−63.
model for the enhanced thermal conductivity of nanofluids. Int. J. Adv. (158) Fares, R.; Mebarek-Oudina, F.; Aissa, A.; Bilal, S. M.; Ö ztop,
Appl. Phys. Res. 2012, 3, 021209. H. Optimal entropy generation in Darcy-Forchheimer magnetized
(140) Wang, B. X.; Zhou, L. P.; Peng, X. F. A fractal model for flow in a square enclosure filled with silver based water nanoliquid. J.
predicting the effective thermal conductivity of liquid with suspension Therm. Anal. Calorim. 2022, 147, 1571.
of nanoparticles. Int. J. Heat Mass Transf 2003, 46, 2665−72. (159) Parvin, S.; Nasrin, R.; Alim, M. A.; Hossain, N. F.; Chamkha,
(141) Afrand, M.; Toghraie, D.; Sina, N. Experimental study on A. Thermal conductivity variation on natural convection flow of
thermal conductivity of water based Fe3O4 nanofluid: development of water−alumina nanofluid in an annulus. Int. J. Heat Mass Transfer
a new correlation and modeled by artificial neural network. Int. 2012, 55, 5268.
Commun. Heat Mass Trans. 2016, 75, 262−9. (160) Mebarek-oudina, F. Convective heat transfer of Titania
(142) Khdher, A. M.; Sidik, N. A. C.; Hamzah, W. A. W.; Mamat, R. nanofluids of different base fluids in cylindrical annulus with discrete
An experimental determination of thermal conductivity and electrical heat source. Heat Transfer Research 2019, 48, 135.
conductivity of bio glycol based Al2O3 nanofluids and development of (161) Zaim, A.; Aissa, A.; Mebarek-Oudina, F.; Mahanthesh, B.;
new correlation. Int. Commun. Heat Mass Trans. 2016, 73, 75−83. Lorenzini, G.; Sahnoun, M.; El Ganaoui, M. Galerkin finite element
(143) Zaraki, A.; Ghalambaz, M.; Chamkha, A. J.; Ghalambaz, M.; analysis of magneto-hydrodynamic natural convection of Cu-water
De Rossi, D. Theoretical analysis of natural convection boundary layer nanoliquid in a baffled U-shaped enclosure. Propulsion and Power
heat and mass transfer of nanofluids: effects of size, shape and type of Research 2020, 9, 383.
nanoparticles, type of base fluid and working temperature. Adv. (162) Chamkha, A. J.; Mansour, M. A.; Rashad, A. M.;
Powder Technol. 2015, 26 (3), 935−46. Kargarsharifabad, H.; Armaghani, T. J. MHD Convection of an
(144) Zainon, S. N. M.; Azmi, W. H. Recent progress on stability Al2O3−Cu/Water Hybrid Nanofluid in an Inclined Porous Cavity
and thermo-physical properties of mono and hybrid towards green with Internal Heat Generation/Absorption. Thermophys Heat Transfer
nanofluids. Micromachines. 2021, 12 (2), 176. 2020, 34, 836.
(145) Arora, N.; Gupta, M. Stability evaluation and enhancement (163) Ganesh, N. V.; Javed, S.; Al-Mdallal, Q. M.; Kalaivanan, R. A.;
methods in nanofluids: a review. AIP Conf Proc. 2021, 2341. Chamkha, J. Numerical study of heat generating ϒ Al2O3 - H2O
(146) Younes, H.; Mao, M.; Murshed, S. S.; Lou, D.; Hong, H.; nanofluid inside a square cavity with multiple obstacles of different
Peterson, G. Nanofluids: Key parameters to enhance thermal shapes. Heliyon 2020, 6, No. e05752.
conductivity and its applications. Applied Thermal Engineering 2022, (164) Raza, J.; Mebarek-Oudina, F.; Chamkha, A. Magneto-
207, 118202. hydrodynamic flow of molybdenum disulfide nanofluid in a channel
(147) Awais, R. M.; Ullah, N.; Ahmad, J.; Sikandar, F.; Ehsan, M. with shape effects. Multidiscipline Modeling in Materials and Structures
M.; Salehin, S.; Bhuiyan, A. A. Heat transfer and pressure drop 2019, 15, 737.

32346 https://doi.org/10.1021/acsomega.4c03279
ACS Omega 2024, 9, 32328−32349
ACS Omega http://pubs.acs.org/journal/acsodf Review

(165) Dogonchi, A. S.; Tayebi, T.; Chamkha, A. J.; Ganji, D. D. (186) Nguyen, C.T.; Desgranges, F.; Galanis, N.; Roy, G.; Mare, T.;
Natural convection analysis in a square enclosure with a wavy circular Boucher, S.; Angue Mintsa, H. Viscosity data for Al2O3-water
heater under magnetic field and nanoparticles. Therm. Anal. Calorim. nanofluid-hysteresis: is heat transfer enhancement using nanofluids
2020, 139, 661. reliable. Int. J. Therm. Sci. 2008, 47, 103−11.
(166) Chamkha, A.; Miroshnichenko, I.; Sheremet, M. Hybrid (187) Abedian, B.; Kachanov, M. On the effective viscosity of
Nanofluid Flow and Heat Transfer Past a Vertical Cylinder in the suspensions. Int. J. Eng. Sci. 2010, 48, 962−5.
Presence of MHD and Heat Generation. Journal of Thermal Science (188) Heyhat, M.M.; Kowsary, F.; Rashidi, A.M.; Momenpour,
and Engineering Applications 2017, 9, No. 041004. M.H.; Amrollahi, A. Experimental investigation of laminar convective
(167) Mebarek-Oudina, F.; Aissa, A.; Mahanthesh, B.; Ö ztop, H. F. heat transfer and pressure drop of water-based Al2O3 nanofluids in
Heat transport of magnetized Newtonian nanoliquids in an annular fully developed flow regime. Exp Therm Fluid Sci. 2013, 44, 483−9.
space between porous vertical cylinders with discrete heat source. (189) Esfe, M. H.; Saedodin, S.; Wongwises, S.; Toghraie, D. An
International Communications in Heat and Mass Transfer 2020, 117, experimental study on the effect of diameter on thermal conductivity
No. 104737. and dynamic viscosity of fe/water nanofluids. J. Therm. Anal. Calorim.
(168) Okonkwo, E. C.; Wole-Osho, I.; Almanassra, I. W.; Abdullatif, 2015, 119, 1817−24.
Y. M.; Al-Ansari, T. An updated review of nanofluids in various heat (190) Hamid, K. A.; Azmi, W. H.; Nabil, M. F.; Mamat, R.; Sharma,
transfer devices. J. Therm. Anal. 2021, 145, 2817−2872. K. V. Experimental investigation of thermal conductivity and dynamic
(169) Zhang, L.; Zhang, A.; Jing, Y.; Qu, P.; Wu, Z. Effect of Particle viscosity on nanoparticle mixture ratios of TiO2− SiO2 nanofluids. Int.
Size on the Heat Transfer Performance of SiO2−Water Nanofluids. J. Heat Mass Transfer 2018, 116, 1143−52.
J.Phys. Chem. C 2021, 125, 13590−13600. (191) Jarahnejad, M.; Haghighi, E. B.; Saleemi, M.; Nikkam, N.;
(170) Mahian, O.; Kianifar, A.; Heris, S. Z.; Wongwises, S. First and Khodabandeh, R.; Palm, B.; et al. Experimental investigation on
second laws analysis of a minichannel-based solar collector using viscosity of water-based Al2O3 and TiO2 nanofluids. Rheol. Acta 2015,
boehmite alumina nanofluids: effects of nanoparticle shape and tube 54, 411−22.
materials. Int. J. Heat Mass Transfer 2014, 78, 1166−1176. (192) Turgut, A.; Saglanmak, S.; Doganay, S. Experimental
(171) Cui, W.; Cao, Z.; Li, X.; Lu, L.; Ma, T.; Wang, Q. investigation on thermal conductıvity and viscosity of nanofluids:
Experimental investigation and artificial intelligent estimation of particle size effect. J. Fac Eng. Archit Gazi Univ. 2016, 31 (1), 95−103.
thermal conductivity of nanofluids with different nanoparticles shapes. (193) Agarwal, D. K.; Vaidyanathan, A.; Sunil Kumar, S.
Powder Technol. 2022, 398, No. 117078. Investigation on convective heat transfer behavior of kerosene-Al2O3
(172) Udawattha, D. S.; Narayana, M.; Wijayarathne, U. P. L. nanofluid. Appl. Therm Eng. 2015, 84, 64−73.
Predicting the effective viscosity of nanofluids based on the rheology (194) Minakov, A. V.; Guzei, D. V.; Pryazhnikov, M. I.; Zhigarev, V.
of suspensions of solid particles. J. King Saud Univ Sci. 2019, 31 (3), A.; Rudyak, V. Y. Study of turbulent heat transfer of the nanofluids in
412−26. a cylindrical channel. Int. J. Heat Mass Transfer 2016, 102, 745−55.
(173) Sundar, L. S.; Singh, M. K.; Sousa, A. C. M. Investigation of (195) He, Y.; Jin, Y.; Chen, H.; Ding, Y.; Cang, D.; Lu, H. Heat
thermal conductivity and viscosity of Fe3O4 nanofluid for heat transfer transfer and flow behaviour of aqueous suspensions of TiO2
applications. Int. Commun. Heat Mass Transfer 2013, 44, 7−14. nanoparticles (nanofluids) flowing upward through a vertical pipe.
(174) Chiam, H. W.; Azmi, W. H.; Usri, N. A.; Mamat, R.; Adam, N. Int. J. Heat Mass Transfer 2007, 50, 2272−81.
M. Thermal conductivity and viscosity of Al2O3 nanofluids for (196) Nguyen, C.T.; Desgranges, F.; Roy, G.; Galanis, N.; Mare, T.;
different based ratio of water and ethylene glycol mixture. Exp Therm Boucher, S.; Angue Mintsa, H. Temperature and particle-size
Fluid Sci. 2017, 81, 420−9. dependent viscosity data for water-based nano-fluids - hysteresis
(175) Naik, M. T.; Sundar, L. S. Investigation into thermophysical phenomenon. Int. J. Heat Fluid Flow. 2007, 28, 1492−506.
properties of glycol based CuO nanofluids for heat transfer (197) Anoop, K. B.; Kabelac, S.; Sundararajan, T.; Das, S. K.
applications. World Acad. Sci. Eng. Technol. 2011, 59, 440−6. Rheological and flow characteristics of nanofluids: influence of
(176) Buonomo, B.; Manca, O.; Marinelli, L.; Nardini, S. Effect of electroviscous effects and particle agglomeration. J. Appl. Phys. 2009,
temperature and sonication time on nanofluid thermal conductivity 106, No. 034909.
measurements by nano-flash method. Appl. Therm Eng. 2015, 91, (198) Kumaresan, V.; Velraj, R. Experimental investigation of the
181−90. thermo-physical properties of water−ethylene glycol mixture based
(177) Keklikcioglu Cakmak, N. The impact of surfactants on the CNT nanofluids. Thermochim. Acta 2012, 545, 180−6.
stability and thermal conductivity of graphene oxide de-ionized water (199) Yarmand, H.; Gharehkhani, S.; Shirazi, S. F. S.; Amiri, A.;
nanofluids. J. Therm. Anal. Calorim. 2020, 139, 1895−1902. Montazer, E.; Arzani, H. K.; et al. Nanofluid based on activated hybrid
(178) Babar, H.; Sajid, M.; Ali, H. Viscosity of hybrid nanofluids: A of biomass carbon/graphene oxide: synthesis, thermo-physical and
critical review. Thermal Science 2019 2019, 23 (3), 1713−1754. electrical properties. Int. Commun. Heat Mass Transfer 2016, 72, 10−
(179) Meyer, J. P.; Adio, S. A.; Sharifpur, M.; Nwosu, P. N. The 5.
viscosity of nanofluids: a review of the theoretical, empirical, and (200) Shin, D, Jo, B, Kwak, H, Banerjee, D. Investigation of high
numerical models. Heat Transfer Eng. 2016, 37, 387−421. temperature nanofluids for solar thermal power conversion and
(180) Einstein, A. A new determination of molecular dimensions. storage applications. 14th International Heat Transfer Conference,
Ann. Phys. 1906, 324 (2), 289−306. ASME: Washington, DC; New York, 2010; pp 583−591.
(181) Brinkman, H. C. The viscosity of concentrated suspensions DOI: 10.1115/IHTC14-23296.
and solutions. J. Chem. Phys. 1952, 20, 571. (201) Doruk, S.; Ş ara, O. N.; Karaipekli, A.; et al. Heat transfer
(182) de Bruijn, H. The viscosity of suspensions of spherical performance of water and Nanoencapsulated n-nonadecane based
particles. (The fundamental η-C and ϕ relations). Recueil des Travaux Nanofluids in a double pipe heat exchanger. Heat Mass Trans. 2017,
Chimiques des Pays-Bas 1942, 61 (12), 863−74. 53, 3399−408.
(183) Batchelor, G. K. The effect of Brownian motion on the bulk (202) Ho, C. J.; Liu, Y. C.; Ghalambaz, M.; Yan, W. M. Forced
stress in a suspension of spherical particles. J. Fluid Mech. 1977, 83, convection heat transfer of nano-encapsulated phase change material
97−117. (NEPCM) suspension in a mini-channel heatsink. Int. J. Heat Mass
(184) Wang, X.; Xu, X.; Choi, S. U. S. Thermal conductivity of Transfer 2020, 155, No. 119858.
nanoparticle− fluid mixture. J. Thermophys Heat Transfer 1999, 13, (203) Ghalambaz, M.; Chamkha, A. J.; Wen, D. Natural convective
474−80. flow and heat transfer of Nano-Encapsulated Phase Change Materials
(185) Dávalos-Orozco, L. A.; Del Castillo, L. F. Hydrodynamic (NEPCMs) in a cavity Natural convective flow and heat transfer of
behavior of suspensions of polar particles. Encyclopedia of Surface and Nano-Encapsulated Phase Change Materials (NEPCMs) in a cavity.
Colloid Science 2016, 3070. Int. J. Heat Mass Transfer 2019, 138, 738−49.

32347 https://doi.org/10.1021/acsomega.4c03279
ACS Omega 2024, 9, 32328−32349
ACS Omega http://pubs.acs.org/journal/acsodf Review

(204) Ghalambaz, M.; Mehryan, S. A. M.; Zahmatkesh, I.; Chamkha, nanoplatelets within a tube enhanced with rotating twisted tape.
A. Free convection heat transfer analysis of a suspension of nano− Powder Technol. 2019, 355, 278−88.
encapsulated phase change materials (NEPCMs) in an inclined (224) Ajeel, R. K.; Salim, W.; Hasnan, K. An experimental
porous cavity. Int. J. Therm Sci. 2020, 157, No. 106503. investigation of thermal-hydraulic performance of silica nanofluid in
(205) Mehryan, S.A.M.; Ghalambaz, M.; Sasani Gargari, L.; Hajjar, corrugated channels. Adv. Powder Technol. 2019, 30, 2262−75.
A.; Sheremet, M. Natural convection flow of a suspension containing (225) Qi, C.; Yang, L.; Chen, T.; Rao, Z. Experimental study on
nano encapsulated phase change particles in an eccentric annulus. J. thermohydraulic performances of TiO2- H2O nanofluids in a
Energy Storage 2020, 28, No. 101236. horizontal elliptical tube. Appl. Therm Eng. 2018, 129, 1315−24.
(206) Rahman, Md. A.; Dhiman, S. K. Performance evaluation of (226) Ajeel, R. K.; Zulkifli, R.; Sopian, K.; Fayyadh, S. N.; Fazlizan,
turbulent circular heat exchanger with a novel flow deflector-type A.; Ibrahim, A. Numerical investigation of binary hybrid nanofluid in
baffle plate. Journal of Engineering Research 2023, No. 100105. new configurations for curved-corrugated channel by thermal
(207) Rahman, Md. A. Study the effect of axially perforated baffle hydraulic performance method. Powder Technol. 2021, 385, 144.
plate with multiple opposite-oriented trapezoidal flow deflector in an (227) Sahoo, R. R. Thermo-hydraulic characteristics of radiator with
air−water tubular heat exchanger. World J. Eng. 2024, DOI: 10.1108/ various shape nanoparticle-based ternary hybrid nanofluid. Powder
WJE-10-2023-0425. Technol. 2020, 370, 19−28.
(208) Rahman, Md. A. Experimental Investigations on Single-Phase (228) Fan, F.; Qi, C.; Tang, J.; Liu, Q.; Wang, X.; Yan, Y. A novel
Heat Transfer Enhancement in an Air-To-Water Heat Exchanger with thermal efficiency analysis on the thermo-hydraulic performance of
Rectangular Perforated Flow Deflector Baffle Plate. Int. J. Thermodyn nanofluids in an improved heat exchange system under adjustable
2023, 26, 31. magnetic field. Appl. Ther Eng. 2020, 179, No. 115688.
(209) Rahman, Md. A. effectiveness of a tubular heat exchanger and (229) Mei, S.; Qi, C.; Liu, M.; Fan, F.; Liang, L. Effects of paralleled
a novel perforated rectangular flow-deflector type baffle plate with magnetic field on thermo-hydraulic performances of Fe3O4- water
opposing orientation. World J. Eng. 2023, DOI: 10.1108/WJE-06- nanofluids in a circular tube. Int. J. Heat Mass Transfer 2019, 134,
2023-0233. 707−21.
(210) Rahman, Md. A. Thermo-fluid performance comparison of an (230) Yılmaz Aydın, D.; Ç iftçi, E.; Gürü, M.; Sözen, A. The impacts
in-line perforated baffle with oppositely oriented rectangular-wing of nanoparticle concentration and surfactant type on thermal
structure in turbulent heat exchanger. Int. J. Fluid Mech. 2024, 51, 15. performance of thermosyphon heat pipe working with bauxite
(211) Rahman, Md. A. The effect of triangular shutter type flow nanofluid. Energy Sour A Recov Util Environ. Eff. 2021, 43, 1524−
deflector perforated baffle plate on the thermofluid performance of a 2548.
heat exchanger. Heat Transfer. 2023, 53 (2), 1−18. (231) Jose, J.; Hotta, T. K. Numerical Investigation on Thermal
(212) Rahman, Md. A. Thermal hydraulic Performance of a Performance of Nanofluid-Assisted Wickless Heat Pipes for Electronic
Turbular Heat Exchanger with In-Line Perforated Baffle With shutter Thermal Management. ASME. J. Thermal Sci. Eng. Appl. 2024, 16 (4),
type Saw Tooth Turbulator. Heat Transfer. 2024, 53, 2234. No. 041009.
(213) Rahman, Md. A. The influence of geometrical and operational (232) Naruka, D. S.; Dwivedi, R.; Singh, P. K. Experimental
parameters on thermofluid performance of discontinuous colonial Investigation to Elucidate the Temporal Effect of Nanofluids on the
self-swirl-inducing baffle plate in a tubular heat exchanger. Heat Thermal Performance of Heat Pipes. Heat Transfer Engineering 2024,
Transfer 2024, 53, 328. 1−12.
(214) Peng, H.; Guo, W.; Li, M. Thermal-hydraulic and (233) Khanlari, A. The effect of utilizing Al2O3- SiO2/Deionized
thermodynamic performances of liquid metal based nanofluid in water hybrid nanofluid in A tube-type heat exchanger. Heat Transf
parabolic trough solar receiver tube. Energy. 2020, 192, No. 116564. Res. 2020, 51 (11), 991−1005.
(215) Nabati Shoghl, S.; Jamali, J.; Keshavarz Moraveji, M. Electrical (234) Variyenli, HI.̇ Experimental and numerical investigation of
conductivity, viscosity, and density of different nanofluids: an heat transfer enhancement in a plate heat exchanger using a fly ash
experimental study. Exp. Fluid Sci. 2016, 74, 339−46. nanofluid. Heat Transf Res. 2019, 50 (15), 1477−94.
(216) Asirvatham, L. G.; Raja, B.; Mohan Lal, D.; Wongwises, S. (235) Said, Z.; Rahman, S.M.A.; El Haj Assad, M.; Alami, A. H. Heat
Convective heat transfer of nanofluids with correlations. Particuology transfer enhancement and life cycle analysis of a Shell-and-Tube Heat
2011, 9, 626−31. Exchanger using stable CuO/water nanofluid. Sustain Energy Technol.
(217) Mikkola, V.; Puupponen, S.; Granbohm, H.; Saari, K.; Ala- Assess. 2019, 31, 306−17.
Nissila, T.; Seppälä, A. Influence of particle properties on convective (236) Khanlari, A.; Sözen, A.; Variyenli, H. I.; Gürü, M. Comparison
heat transfer of nanofluids. Int. J. Therm Sci. 2018, 124, 187−95. between heat transfer characteristics of TiO2/ deionized water and
(218) Khoshvaght-Aliabadi, M. Thermal performance of plate-fin kaolin/deionized water nanofluids in the plate heat exchanger. Heat
heat exchanger using passive techniques: vortex-generator and Transf Res. 2019, 50 (5), 435−50.
nanofluid. Heat Mass Transfer 2016, 52, 819−28. (237) Zheng, M.; Han, D.; Asif, F.; Si, Z. Effect of Al2O3/water
(219) Khoshvaght-Aliabadi, M.; Hassani, S. M.; Mazloumi, S. H. Nanofluid on Heat Transfer of Turbulent Flow in the Inner Pipe of a
Comparison of hydrothermal performance between plate fins and Double-Pipe Heat Exchanger. Heat Mass. Transfer 2020, 56, 1127−
platepin fins subject to nanofluid-cooled corrugated miniature heat 1140.
sinks. Microelectron Reliab. 2017, 70, 84−96. (238) Raei, B.; Shahraki, F.; Jamialahmadi, M.; Peyghambarzadeh, S.
(220) Sarafraz, M. M.; Arya, H.; Arjomandi, M. Thermal and M. Experimental Study on the Heat Transfer and Flow Properties of
hydraulic analysis of a rectangular microchannel with gallium-copper γ-Al2O3/ water Nanofluid in a Double-Tube Heat Exchanger. J.
oxide nano-suspension. J. Mol. Liq. 2018, 263, No. 382. Therm. Anal. Calorim. 2017, 127, 2561−2575.
(221) Akcay, S.; Akdağ, Ü ; Hacıhafızoğu, O.; Demiral, D. The effect (239) Singh, S. K.; Sarkar, J. Improving Hydrothermal Performance
on heat transfer of pulsating flow of the Al2O3- water nanofluid of Double-Tube Heat Exchanger with Modified Twisted Tape Inserts
passing through the tube bundle. DÜ MF Mühendislik Dergisi. 2019, Using Hybrid Nanofluid. J. Therm. Anal. Calorim. 2021, 143, 4287−
10, 621−31. 4298.
(222) Sarafraz, M. M.; Arjomandi, M. Demonstration of plausible (240) Duangthongsuk, W.; Wongwises, S. Heat Transfer Enhance-
application of gallium nano-suspension in microchannel solar thermal ment and Pressure Drop Characteristics of TiO2-Water Nanofluid in a
receiver: experimental assessment of thermohydraulic performance of Double-Tube Counter Flow Heat Exchanger. Int. J. Heat Mass
microchannel. Int. Commun. Heat Mass Transfer 2018, 94, 39−46. Transfer 2009, 52, 2059−2067.
(223) Bahiraei, M.; Mazaheri, N.; Aliee, F.; Safaei, M. R. Thermo- (241) Arya, H.; Sarafraz, M. M.; Pourmehran, O.; Arjomandi, M.
hydraulic performance of a biological nanofluid containing graphene Heat Transfer and Pressure Drop Characteristics of MgO Nanofluid

32348 https://doi.org/10.1021/acsomega.4c03279
ACS Omega 2024, 9, 32328−32349
ACS Omega http://pubs.acs.org/journal/acsodf Review

in a Double Pipe Heat Exchanger. Heat Mass. Transfer 2019, 55,

1769−1781.
(242) Zheng, D.; Wang, J.; Pang, Y.; Chen, Z.; Sunden, B. Heat
Transfer Performance and Friction Factor of Various Nanofluids in a
Double-Tube Counter Flow Heat Exchanger. Therm. Sci. 2020, 24,
3601−3612.
(243) Kumar, V.; Tiwari, A. K.; Ghosh, S. K. Effect of Variable
Spacing on Performance of Plate Heat Exchanger Using Nanofluids.
Energy. 2016, 114, 1107−1119.
(244) Wang, Z.; Wu, Z.; Han, F.; Wadsö, L.; Sundén, B.
Experimental Comparative Evaluation of a Graphene Nanofluid
Coolant in Miniature Plate Heat Exchanger. Int. J. Therm. Sci. 2018,
130, 148−156.
(245) Tiwari, A. K.; Ghosh, P.; Sarkar, J. Performance Comparison
of the Plate Heat Exchanger Using Different Nanofluids. Exp. Therm.
Fluid Sci. 2013, 49, 141−151.
(246) Bhattad, A.; Sarkar, J. Hydrothermal Performance of Plate
Heat Exchanger with an Alumina-Graphene Hybrid Nanofluid:
Experimental Study. J. Braz. Soc. Mech. Sci. Eng. 2020, 42, 1−10.
(247) Elsaid, K.; Olabi, A. G.; Wilberforce, T.; Abdelkareem, M. A.;
Sayed, E. T. Environmental impacts of nanofluids: a review. Sci. Total
Environ. 2021, 763, No. 144202.
(248) Barberio, G.; Scalbi, S.; Buttol, P.; Masoni, P.; Righi, S.
Combining life cycle assessment and qualitative risk assessment: the
case study of alumina nanofluid production. Sci. Total Environ. 2014,
496, 122−31.
(249) Michael Joseph Stalin, P.; Arjunan, T. V.; Matheswaran, M.
M.; Dolli, H.; Sadanandam, N.; et al. Energy, economic and
environmental investigation of a flat plate solar collector with
CeO2/water nanofluid. J. Therm Anal Calorim. 2020, 139, 3219−33.
(250) Sharafeldin, M. A.; Gróf, G.; Abu-Nada, E.; Mahian, O.
Evacuated tube solar collector performance using copper nanofluid:
energy and environmental analysis. Appl. Therm Eng. 2019, 162,
114205.
(251) Sundar, L. S.; Ramana, E. V.; Said, Z.; Punnaiah, V.; Chandra
Mouli, K. V. V.; Sousa, A. C. M. Properties, heat transfer, energy
efficiency and environmental emissions analysis of flat plate solar
collector using Nanodiamond Nanofluids. Diam Relat Mater. 2020,
110, 108115.

32349 https://doi.org/10.1021/acsomega.4c03279
ACS Omega 2024, 9, 32328−32349