THERMAL ANALYSIS OF PISTON USING

HYPERMESH AND LS-DYNA

A Skill Advanced Course

(PRATICAL FINITE ELEMENT ANALYSIS USING HYPERMESH & LS-DYNA)

report submitted to
JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY, KAKINADA

In partial fulfillment for the award of the Degree of

BACHELOR OF TECHNOLOGY
IN
MECHANICAL ENGINEERING
Submitted by

DOPPALA SRINIVAS
21761A0310
Under the guidance of

Mr. K. VISHWANADH
Sr. Assistant Professor

DEPARTMENT OF MECHANICAL ENGINEERING

LAKIREDDY BALI REDDY COLLEGE OF ENGINEERING (AUTONOMOUS)
(Approved by AICTE, Affiliated to JNTUK, KAKINADA, Accredited by NBA (Tier-I),
NAAC and an ISO 9001-2015 certified Institution) L. B. REDDY NAGAR, MYLAVARAM,
KRISHNA DIST –521230 ANDHRA PRADESH
November - 2023
 LAKIREDDY BALI REDDY COLLEGE OF ENGINEERING

DEPARTMENT OF MECHANICAL ENGINEERING

CERTIFICATE

This is to certify that the Skill Advanced Course (PRATICAL FINITE ELEMENT
ANALYSIS USING HYPERMESH AND LS-DYNA) report entitled “THERMAL
ANALYSIS OF PISTON USING HYPERMESH & LS-DYNA” that is being submitted by
DOPPALA SRINIVAS bearing register number 21761A0310 in partial fulfilment for the award of
the degree of Bachelor of Technology in Mechanical Engineering is a record of Skill
Advanced Course-II, work carried out by him under our guidance and supervision.

Staff In-charge Head of the Department

Mr. K. Vishwanadh Dr. M. B. S. Sreekar Reddy

Internal Examiner External Examiner

 ACKNOWLEDGEMENT

The Satisfaction that accompanies that the successful completion of any task
would be incomplete without the mention of the people whose cease less co-
operation made it possible, whose constant guidance and encouragement crown
all efforts with success.

I humbly express my thanks to our management and Principal Dr. K. Appa Rao
for extending their support for providing us with an environment to complete
our internship successfully.

I indebted to our Head of the Department Dr. M. B. S. Sreekar Reddy sir and Dr.
S. Picchi Reddy s i r who modelled us both technically and morally for
achieving greater success in life.

I humbly express my thanks to my mentor B. R. M. V. Krishna and guidance of

Mr. K. Viswanadh sir forgiving timely valuable suggestions and encouragement
that make the completion of the internship successfully.

I would like to thank all the teaching and non- teaching staff members of
Mechanical Engineering, who have extended their full co-operation during the
course of this work.

Doppala Srinivas
(21761A0310)
S. No. CHAPTER Pg. No.

1. INTRODUCTION TO HYPERMESH AND LS-DYNA

1-3

2. INTRODUCTION TO HYPERMESH WORKSPACE 4-8

3. INTRODUCTION TO PISTON 9-10

4. PROCEDURE FOR THE ANALYSIS 10-18

5. CONCLUSION 18

6. REFERENCES 19
 1. INTRODUCTION TO HYPERMESH AND LS-DYNA

1.1 Hyper Mesh Software

Altair Hyper Mesh is a high-performance finite element pre-processor to prepare even the
largest models, starting from import of CAD geometry to exporting an analysis run for various
disciplines.

• Hyper Works delivers easy-to-learn solution- and domain-specific workflows across a

growing number of engineering applications to increase team productivity and accelerate
the development of today’s increasingly complex, connected products.
• Sim Lab minimizes the time users must spend creating finite element models and
interpreting results through automation. It can accurately analyze the performance
of complex assemblies in multiple physics types, including structural, thermal, and
fluid dynamics.
• Users can learn Inspire in just a few hours. Its intuitive interface provides the dependable
Altair solver power for analysts and designers so they perform what-if studies faster,
easier, and earlier. Inspire encourages collaboration, optimizes product design, and reduces
time to market.
Mesh generation is the premise of finite element analysis, Hyper Mesh as a high performance
finite element preprocessor, By analyzing the specific example of bearing gear system, the key
problems of geometry cleaning and mesh generation in the process of finite element preprocessing
are studied. The influence of different modeling methods on mesh generation is analyzed.
According to the basic principle of finite element mesh division, through the good interface
between Hyper Mesh and CAD and CAE software, the geometric model import and modal
analysis are realized, and the quality and efficiency of finite element analysis are improved.

The one-dimensional hyper mesh, referred to as a cluster, forms the basic topology upon which
higher- dimensional hyper mesh structures are formed. The cluster is a hypergraph consisting of k
nodes connected within a single hop. A k-array n-dimensional hyper mesh, is a regular
hypergraph with N=kn nodes, formed by taking the Cartesian n-product of the cluster
topology. This has the effect of imposing the cluster organization in every dimension, making
each node equally a member of n independent.

Altair Hyper Mesh is a high-performance finite element pre-processor to prepare even the
largest models, starting from import of CAD geometry to exporting an analysis run for various
disciplines.
1.2 LS-DYNA SOFTWARE

Ansys LS-DYNA is a general-purpose finite element software solution capable of simulating

complex, real-world problems such as impact and crash related problems in automotive
industries, as well as blade containment, bird strike, metal forming, fluid splashing, metal
cutting, blast and biomechanics in other industries.

It is a post processing soft ware

The key features of the software: -

➢ Understand the keyword structure of LS-DYNA

➢ Understand key concepts of penalty and kinematic contacts
➢ Have awareness of unit consistency while setting up your units for materials, element
length and time
➢ Distinguish between an acceptable "Normal Termination" and incorrect results

➢ ANSYSAUTODYN-Explicit dynamic solver for transient non‐ linear simulations

involving large deformations and strains, non‐ linear material behaviour, non‐linear
buckling, complex contact, fragmentation, and shock wave propagation.
➢ ANSYS LS ‐DYNA–LSTC’s LS‐DYNA explicit dynamic solver technology with the
pre/postprocessing power of ANSYS software. This powerful pairing can be used to
simulate crash tests, metal forging, stamping, and catastrophic failures.
1.3 STEPS INVOLVED IN THE ANALYSIS OF A COMPONENT

PRE-PROCESSING

SOLVER

POST-PROCESSING
2.1 INTRODUCTION HYPERMESH WORKSPACE

Hyper Mesh Introduction: The User Interface

Fig 2.1

• Graphics area – displays the model

• Toolbar – Gives access to commonly used tools via icons

• Pull Down Menu – places functionality into groups, accessible via pull downs

• Menu Pages – divides the main menu into groups based on function

• Main Menu – contains “panels” grouped in columns

• Panels – menu items / functions for interacting with HyperMesh

• Sub-panels – divides panel into similar tasks related to panel’s main function
 • Command Window – lets the user type in and execute tcl commands
• Available through the View drop down menu (turned off by default)

Tab Area – contains the following tabs:

• Solver, Model, Utility, Include, Import, Export, Connector, Entity State, etc.
• Status Bar – shows status of operations being performed
• Indicates the “current” Include file, Component Collector, and Load Collector
2.2 FILE OPERATIONS
• General terminology:

▪ Open: Loads a file into Hypermesh replacing the current session

▪ Save: Saves the current session contents to the file name specified
▪ Import : Loads a file into HyperMesh, merging with the current contents
▪ Export : Saves data to the file name specified
• Generally refers to file types other than a Hypermesh binary file
2.3 IMPORTING GEOMETRY

• Import geometry data via:

• File > Import > Geometry drop-down menu

• Toolbar > > Geometry

• Common types of geometry files supported:
• Unigraphics (NX2, NX3, NX4, NX5, NX6)
• CATIA (V4 & V5)
• IGES
• STEP
2.4 MODEL ORGANIZATION: Collectors

• The Hyper Mesh model is organized using “collectors”

• There are many types of collectors

• Most entities in Hyper Mesh must be placed in a collector

• Each collector type holds a specific type of entity

 Collector Types Table – 2.1
Component Elements, Points, Lines, Surfaces, Connectors
Multibody Ellipsoids, Mbjoints, Mbplanes, Sensors
Assembly Components, Multibodies, Assemblies
Load Collector Loads, Equations
Material

none (materials and properties don’t contain

Property otherentitiesbut are
still treated as collectors)
System Collector Systems
Vector Collector Vectors
Beam Beam Sections
Section
Collector

2.5 MODEL ORGANIZATION

Model browser

Create, delete, and rename collectors

Edit collector attributes
Organize collectors into assemblies
Drag and drop

Fig 2.3
 Right-Click onCollector for advanced
options

Fig 2.4
2.6 MODEL ORGANIZATIONS: Tools

• Panels

• Collectors – Create new collectors

• Model Browser – Set the current collector for various entity types
• Organize – Move entities into a different collector than the one they are
currently contained in
• Rename – Change the name of an existing collector

• Reorder

• Collectors appear in a certain order when presented in a list to pick from

• Reorder allows the order the collectors appear in to be changed
• Delete – Delete entities or collectors
2.1 STATIC STRUCTURAL
A static structural analysis calculates the effect of steady (or static) loading conditions on a
structure, while ignoring inertia and damping effects, such as those caused by time varying
loads. Static structural analyses are used for simple linear calculations as well as complex
material, geometric and contact nonlinear calculations. The analysis results help to identify weak
areas with low strength and durability.

Fig 2.4
2.2 COMMANDS USED IN GEOMETRY

1. LINE– It can be used for making simple lines in the drawing.

2. RECTANGLE– This command will make a rectangle in the drawing.

3. CIRCLE– It is the command used for making a circle.

4. POLYGON - This command can be used for making a polygon.

5. POLY LINE– This command can be used to make a poly line.

6. ARC – This command can be used to make an arc.

7. ARRAY – This command can be used to make a rectangle, polar or path array.

8. TRIM– This command can be used to trim the objects.

9. Fillet- This is used to fill the edges of the body

10. Pad- This is used to create a 3D surface.

Fig 2.5
3.1 INTRODUCTION TO PISTON

A piston is a component of reciprocating engines, reciprocating pumps, gas compressors, hydraulic

cylinders and pneumatic cylinders, among other similar mechanisms. It is the moving component
that is contained by a cylinder and is made gas-tight by piston rings. In an engine, its purpose
is to transfer force from expanding gas in the cylinder to the crankshaft via a piston rod and/or
connecting rod. In a pump, the function is reversed and force is transferred from the crankshaft
to the piston for the purpose of compressing or ejecting the fluid in the cylinder. In some engines,
the piston also acts as a valve by covering and uncovering ports in the cylinder. An internal
combustion engine is acted upon by the pressure of the expanding combustion gases in the
combustion chamber space at the top of the cylinder. This force then acts downwards through the
connecting rod and onto the crankshaft. The connecting rod is attached to the piston by a
swivelling gudgeon pin (US: wrist pin). This pin is mounted within the piston: unlike the
steam engine, there is no piston rod or crosshead (except big two stroke engines).
This type of piston is widely used in car diesel engines. According to purpose, super charging level
and working conditions of engines the shape and proportions can be changed.
High-power diesel engines work in difficult conditions. Maximum pressure in the combustion
chamber can reach 20 MPa and the maximum temperature of some piston surfaces can exceed450
°C. It is possible to improve piston cooling by creating a special cooling cavity. Injector
supplies this cooling cavity with oil through oil supply channel. For better temperature
reduction construction should be carefully calculated and analysed. Oil flow in the cooling
cavity should be not less than 80% of the oil flow through the injector.
The pin itself is of hardened steel and is fixed in the piston, but free to move in the connecting rod.
A few designs use a 'fully floating' design that is loose in both components. All pins must be
prevented from moving sideways and the ends of the pin digging into the cylinder wall, usually by
circlips.
Pistons are usually cast or forged from aluminium alloys. For better strength and fatigue life, some
racing pistons may be forged instead. Billet pistons are also used in racing engines because they
do not rely on the size and architecture of available forgings, allowing for last- minute design
changes. Although not commonly visible to the naked eye, pistons themselves are designed with a
certain level of ovality and profile taper, meaning they are not perfectly round, and their
diameter is larger near the bottom of the skirt than at the crown.
Early pistons were of cast iron, but there were obvious benefits for engine balancing if a lighter
alloy could be used. To produce pistons that could survive engine combustion temperatures, it
was necessary to develop new alloys such as Y alloy and Hiduminium, specifically for use as
pistons.

3.2 THERMAL ANALYSIS OF PISTON

Pistons are commonly made up of aluminum or cast-iron alloys. By observing the analysis
results, we can decide whether our designed piston is safe or not under applied load
conditions. The thermal flux and thermal temperature distribution is analyzed by applying
temperatures on the piston surface in Thermal analysis.
The thermal conductivity of aluminum alloy piston material increases with the increase of
temperature. There is an obvious temperature gradient from the piston head to the piston skirt.
High thermal conductivity can reduce the surface temperature of the piston head.
Thermal analysis is widely used in combustion research for both fundamental and practical
investigations. Efficient combustion of solid fuels in power plants requires understanding of
properties and behavior of fuel and ash under a wide range of conditions.
4.1 PROCEDURE FOR THE ANALYSIS
This structural analysis consists of three steps

➢ Pre-processing
➢ Solving
➢ Post-processing

PRE-PROCESSING

Preprocessing consists of 11 steps

1. Meshing
2. Properties
3. Material
4. Assembly
5. Intersections and penetrations
6. Connections
7. Loads
8. Boundary conditions
9. Contacts
10. Control cards

11. Data base cards

Step1 :-
After the 3D modeling is completed in the CATIA software and save the file. The saved file is
converted into STEP file. Now open the Hyper mesh software and import the geometry from the
import panel and save it with the proper name.

Fig 4.1
Step2:-
The geometry is appeared on the hyper mesh workspace. Now delete the solids if any present by
clicking (f2) and delete the entities.

Fig 4.2

Step3:-
After deletion of solids if any duplicate surfaces are appeared in the geometry now delete the
duplicate surfaces. Go to the
Geometry – defeature—duplicates – select all – delete.
Selecting the arc centre node.

Fig 4.3
13 | P a g
Step4:-

Meshing operation is performed, because it helps the infinite degree of freedom is converted into
finite degree of freedom. Generate the 2D mesh, go to the

2D – auto mesh – select all surfaces – set the element length – generate.

Fig 4.4

Step5:-
After 2D meshing is completed now check the total geometry and find the free edges if in case
any free edges are appeared delete the free edges. The component must enclose.

Fig 4.5
 Step6:-
Generate the 3D mesh in 3D panel

Fig 4.6

Step 7 :-
After completing the both 2D and 3D mesh. Now create the load collector as needed and apply
to node points and assign them to the load steps

Fig 4.7
Step8:-

Assign the material. Go to the tool set, click the create cards. Select the required material
(steel) and assign to components.

Fig 4.8

Step9:-
After assign the material. Now assign the properties. Go to the tool set, click the create card select
the properties and assign property to components.

Fig 4.9
Step10:-
Same steps are followed and give the convective properties.

Fig 4.10

Step11:-

After all the steps are completed. Now save the file and export to export to solver deck

Fig 4.11
Solver:-

Import the k file in ls run or ls manager and run the file

Fig 4.12

Once the file is terminated normally its ready for post processing in this we see the deformations
and loads acting on it.

POST-PROCESSING:-
Grid Temperature

Fig 4.13
Element temperature gradients (Mag).

Fig 4.14

Element Fluxes (Mag).

Fig 4.15
Heat Transfer Analysis of Element Temperature Gradient (Mag).

Fig 4.16
 5. CONCLUSION

The use of the import function in HYPER MESH AND LS-DYNA definitely has some
advantages. It can help to reduce the time it takes to produce the drawings needed in
the work environment. However, if the individual that has created the imported file
does not receive credit for their work, problems may arise in the future. As well ,by
using the function people may slowly start to place a lesser value on the intellectual
property of others, which will undoubtedly create future conflict .The use of the import
function may also be relied on heavily in order to create efficiencies within the
industry .This could possibly lead to a decrease in the rate of innovation .It's obvious
that the import function has a place in the building industry ,but its use will have to be
regulated in order to create a balance between the negative and the positive effects it
creates .

Mesh generation is the premise of finite element analysis, Hyper Mesh as a high
performance finite element preprocessor, By analyzing the specific example of
bearing gear system, the key problems of geometry cleaning and mesh generation in
the process of finite element preprocessing are studied. The influence of different
modeling methods on mesh generation is analyzed. According to the basic principle
of finite element mesh division, through the good interface between HyperMesh and
CAD and CAE software, the geometric model import and modal analysis are realized,
and the quality and efficiency of finite element analysis are improved.
 REFERENCES

❖ Singh, U., Lingwal, J., Rathore, A., Sharma, S., Kaushik, V.: Comparative analysis
of different materials for piston and justification. Mater. Today Proc. 25(4), 925–930
(2020).
❖ Sharma, J.K., Raj, R., Kumar, S., Jain, R.K., Pandey, M.: Finite element modelling of
Lanthanum Cerate (La2Ce2O7) coated piston used in a diesel engine. Case Stud.
Therm. Eng. 25, 100865 (2021).
❖ Zhaoju, Q., Yingsong, L., Zhenzhong, Y., Duan, J., Lijun, W.: Diesel engine
piston thermo-mechanical coupling simulation and multidisciplinary design
optimization. Case Stud. Therm. Eng. 15, 100527 (2019).
❖ Sroka, Z.J.: Thermal load of tuned piston. Arch. Civ. Mech. Eng. 12(3), 342–347 (2012).
❖ Bagha, A.K., Bahl, S.: Finite element analysis of VGCF/pp reinforced square
representative volume element to predict its mechanical properties for different.
Mater. Today Proc. 39(1), 54–59 (2021).
❖ Satyanarayana, K., Rao, P.M., Kumar, I.N., Prasad, V., Rao, T.H.: Some studies
on stress analysis of a sundry variable. Mater. Today Proc. 5(9), 18251–18259
(2018).
❖ Gopal, G., Kumar, L.S., Reddy, K.V., Rao, M.U., Srinivasulu, G.: Analysis of
piston, connecting rod and crank shaft assembly. Mater. Today Proc. 4(8), 7810–
7819 (2017).
❖ Roychoudhury, A., Banerjee, A., Mishra, P.C., Khoshnaw, F.: An FEA material
strength modelling of a coated engine piston. Mater. Today Proc. 44(1), 1320–1325
(2021).
❖ Saxena, A., Godara, S.S., Chouhan, M.K., Saxena, K.: Effect of die geometry on
thermal fatigue analysis of aluminium alloy (A02240) dies of low melting point
alloys casting using pressure die casting process. Adv. Mater. Process. Technol.
(2021).
❖ Godara, S.S., Saxena, A., Chouhan, M.K., Saxena, K., Gupta, N.: Thermal fatigue
analysis of Saffil reinforced aluminium alloys using pressure die casting process.
Adv. Mater. Process. Technol. (2021).