INSTITUTE OF AERONAUTICAL ENGINEERING

(Autonomous)
Dundigal, Hyderabad - 500 043

MECHANICAL ENGINEERING
QUESTION BANK

Course Title THERMAL ENGINEERING SYSTEMS

Course Code AMED13
Program B.Tech
Semester IV ME
Course Type Core
Regulation IARE -BT23
Theory Practical
Course Structure Lecture Tutorials Credits Laboratory Credits
3 0 3 - -
Course Coordinator Dr. K. Ch Apparao , Associate Professor

COURSE OBJECTIVES:
The students will try to learn:

I The concepts related to the operation of internal combustion engines based upon
the fundamental engineering sciences of thermodynamics.
II The techniques for improving the efficiencies and performance of compressors and
refrigeration systems retained to practical applications such as irrigation, air
conditioning and refining oil and gas..
III The performance of Heat Engines in real-time applications by applying the various
testing parameters of an engine.

COURSE OUTCOMES:
After successful completion of the course, students should be able to:
CO 1 Classify the fuel injection and ignition system to pretend the Understand
application of combustion chamber types such as T-head and
overhead.
CO 1 select normal and abnormal combustion which affects the Remember
importance of flame front and flame propagation and knocking of
engine variables
CO 3 Experiment with the testing and performance of an Internal Apply
combustion engine such as fuel consumption, power, efficiencies,
and heat balance sheet.
 CO 4 Explain the principle of operation related to the working of fan, Understand
blowers and compressors and their applications in industries/
factories and how do they differ with each other.
CO 5 Solve numerically related to the performance of all the variations Apply
in the velocity triangles pretended to single and multi-stage air
compressors with industrial applications.
CO 6 Outline the basic concepts of refrigeration and vapor compression Understand
refrigeration systems with superheating and sub cooling to find out
COP of refrigeration.

QUESTION BANK:
MODULE I
IC ENGINES,FUEL INJECTION AND LUBRICATION SYSTEMS
PART-A PROBLEM SOLVING AND CRITICAL THINKING QUESTIONS
1 What are the homogeneous Understand The learner to recall the CO 1
and heterogeneous various mixtures of fuels
mixtures? In which engines and explain the connection
these mixtures are used? between homogeneous and
Explain. heterogeneous mixtures.
2 What is the importance of Understand The learner to recall the CO 1
additives in lubricants? concept of various additives
and considerations and then
explain the characteristics
additives in lubricants.
3 Explain the basic energy Understand The learner to recall the CO 1
requirements for spark concept of various energy
ignition engine. requirements and then
classify the importance of
energy requirements spark
ignition engine.
4 What are the different Understand The learner to recall the CO 1
variables that effects concept of knocking and
knocking in a CI engine can then explain how to control
an operator usually able to hose effects.
control hose effects explain.
5 Explain the process of Understand The learner to recall the CO 1
ignition delay of CI engine concept of ignition delay of
while representing on CI engine and then explain
pressure time diagram. the pressure timing diagram
6 Illustrate with diagram the Understand The learner to recall the CO 1
effect of ignition delay on concept of ignition delay of
the rate of pressurized in CI engine and then explain
the CI engine. the pressure timing diagram

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7 What is meant by crank Understand The learner to recall the CO 1
case ventilation? Explain concepts of ventilation and
the details? then explain its technology
cranks case ventilation.
8 Give a brief account of air Understand The learner to define the CO 1
pollution due to engine emissions and explain the
exhaust. air pollution due to engine
exhaust.
9 What are the causes and Remember — CO 1
problems of improper
combustion of IC engines?
10 What are the different Understand The learner to recall the CO 1
variables that effects concept of Knocking and
knocking in an SI engine can explain the effects of
an operator usually able to knocking in an SI engine.
control hose effects explain?
PART B-LONG ANSWER QUESTIONS
1 Give classification of IC Understand The learner to define the CO 1
Engines. Internal combustion engine
and classify the list in IC
engines
2 Distinguish between SI Understand The learner to recall the CO 1
engines and CI engines? concepts of SI and CI
engine systems and then
identify the differences of it
3 Sketch and explain the valve Understand The learner to recall the CO 1
timing diagram of a four concepts of 4-Stroke engine
stroke Otto cycle engine? and then explain the valve
timing diagram for Otto
cycle
4 In what respect two stroke Understand The learner to recall the CO 1
engines differs from 4-stroke concepts of 2 and 4-Stroke
engine Discuss. engine process adapted in
IC engines
5 Explain fuel injection Remember — CO 1
system of an SI engine?
6 What are the different Understand The learner to define CO 1
lubrication systems lubricants and then
available for IC engines? describes about availability
of various lubricants in IC
engine.

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7 Discuss the importance of Understand The learner to define cooling CO 1
cooling system for an IC system and then describes
engines. Describe different about availability of various
cooling systems? coolants used in IC engine.
8 List out the properties of Understand The learner to recall the CO 1
fuel for (i) SI engine (ii) CI concepts of SI and CI engine
engine. systems and then identify
the differences of fuels.
9 Explain lubrication system Remember — CO 1
for IC engines?
10 Explain cooling system for Understand The learners to define the CO 1
IC engines? concepts of rapid
prototyping then explain its
importance in development
of product.
11 What is the main difference Understand The learner to recall the CO 1
between an Otto cycle and concepts of Otto cycle and
Diesel cycle? Derive the Diesel cycle and then
expression for mean effective explain its differences.
pressure of the Diesel cycle.
12 Explain with a neat sketch Remember — CO 1
the working principle of a
mechanical governor.
13 Explain why a rich mixture Understand The learner to recall the CO 1
is required for the following concepts of the fuel mixture
1) Idling 2) Maximum process and explain the
power 3) Sudden process of mixing of fuel
acceleration consumption.
14 Describe the essential part Remember — CO 1
of a modern carburetor.
15 What is the purpose of Understand The learner to recall the CO 1
using a governor in CI concepts of governor in CI
engines? What are the two engine and then explain
major types of governors? major types in governors.
16 Draw a schematic diagram Remember — CO 1
of fuel feed pump and
explain its working
principle.
17 What are the different kinds Understand The learner to define all the CO 1
of fuels used in an IC fundamental concepts of
engine? fuels and explains the types
of fuels and its
characteristics.

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18 How are SI and CI engine Understand The learner to recall the CO 1
fuels rated? concepts of SI and CI
engine systems and then
identify the differences of it
19 Explain reversible and Remember — CO 1
irreversible processes. Is it
possible to realize these
processes?
20 Explain briefly the Diesel Understand The learner to recall the CO 1
cycle with the help of P-V concepts of SI and CI
and T-S diagrams and engine systems and then
derive an expression for the identify the P-V and T-S
ideal efficiency of a Diesel diagram for Diesel cycle.
cycle.
PART C-SHORT ANSWER QUESTIONS
1 What is valve timing Remember — CO 1
diagram why the inlet valve
is opened before TDC and
closed after BDC?
2 What is combustion Remember — CO 1
efficiency and combustion
back duration?
3 What is fluid friction in an Remember — CO 1
engine?
4 What are the products Remember — CO 1
formed during combustion
process?
5 What is an internal Remember — CO 1
combustion engine?
6 What is scavenging? Remember — CO 1
7 What is meant by Remember — CO 1
compression ratio?
8 Define firing order. Remember — CO 1
9 What do you mean by SFC? Understand The Learner to recall the CO 1
types of fuel consumption
and then explain the
statement about its specific
fuel and its volume to the
machine.
10 Define mean effective Remember — CO 1
pressure.
11 Obtain the expression for Remember — CO 1
mean effective pressure of
an Otto cycle.

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12 List the three principal Remember — CO 1
factors that influence engine
performance.
13 What are the different kinds Remember — CO 1
of fuels used in an IC?
14 Briefly explain the Remember — CO 1
petroleum refining process.
15 What are the important Remember — CO 1
qualities of SI and CI engine
fuel?
16 How are SI and CI engine Remember — CO 1
fuels rated?
17 What are the functional Remember — CO 1
requirements of an injection
system?
18 How the injection system Remember — CO 1
classified?
19 Define carburetion. Remember — CO 1
20 With a neat sketch explain Remember — CO 1
an induction coil.
MODULE II
COMBUSTION IN SI AND CI ENGINES
PART-A PROBLEM SOLVING AND CRITICAL THINKING QUESTIONS
1 What are the harmful effect Understand The learner to recall the CO 2
of overheating of an engine fuels used in IC engine then
explain. explain the requirements of
fuel for a diesel engine.
2 Why battery ignition Understand The learner to recall the CO 2
system is preferred in most principles of ignition and
of the engines. then explain the battery
ignition system is preferred
in most of the engines
3 What are the effects of Understand The learner to recall the CO 2
super charging on engine principles of super charging
performance? and then explain the engine
process used for super
charging.
4 How does scavenging takes Understand The learner to recall the CO 2
place in 2 stroke petrol principles of 2 stroke petrol
engine? engine and then explain the
scavenging takes place in 2
stroke petrol engine.

Page 6
5 What are the undesirable Understand The learner to recall the CO 2
effects if an engine under fuels used in IC engine then
cool? explain the requirements of
fuel for a diesel engine.
6 How liquid cooling system is Understand The learner to recall the CO 2
better than air cooling fuels used in IC engine then
system in an IC engine. explain the requirements of
fuel for a diesel engine.
7 Find the mean effective Remember — CO 2
pressure and torque
developed by the IC engine.
8 What do u mean by charge? Remember — CO 2
What type of charge to be
sent for petrol engine for
better performance?
9 Why firing order is UnderstandThe learner to recall the CO 2
important to run an IC principles of firing order
engine. Mention firing order then explain its working on
of four - stroke four firing order of four - stroke
cylinders, six cylinder four cylinders, six cylinder
engines. engines.
10 Why the actual efficiency Understand The learner to recall the CO 2
much lower than air principle of air standard
standard efficiency explain efficiency then explains
with major losses. various parameters such as
major losses in this process.
PART B-LONG ANSWER QUESTIONS
1 State and explain different Understand The learner to recall the CO 2
combustion stages in SI principles of combustion
engine. stages and then explain
various stages in combustion
stages in SI engine.
2 State and explain different Understand The learner to recall the CO 2
combustion stages in CI principles of combustion
engine. stages and then explain
various stages in combustion
stages in CI engine.
3 Explain knocking, Understand The learner to recall the CO 2
properties and its effects in concept of knocking and
CI engine. then explain various
properties in CI engine.

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4 Explain different types of Understand The learner to recall the CO 2
combustion chambers in SI concept of combustion and
and CI engines. then explain various
combustion chambers in SI
and CI engines.
5 a. Explain the need for air Analysis The learner to recall the CO 2
motion and types. b. concepts of knocking and
Factors influencing knocking then explain the type of air
in SI and CI engine. motion and then apply
different factors influencing
in knocking and analyze the
Factors in knocking of SI
and CI engine.
6 W What are the Understand The learner to recall the CO 2
requirements of fuel for a fuels used in IC engine then
diesel engine? explain the requirements of
fuel for a diesel engine.
7 Differentiate between Understand The learner to recall the CO 2
normal combustion and concepts of combustion in
abnormal combustion SI engine then compare
phenomena in case of SI normal combustion and
Engine. abnormal combustion.
8 What is the importance of Apply The learner to recall the CO 2
variables like flame speed concepts of engine variables,
flame front in case of delay understand the principles of
period. working of flame speed and
apply them to compute
flame speed and flame front
of delay period.
9 Ex Explain knocking Remember — CO 2
additives in combustion of
an SI engine?
10 Di Discuss air flow Understand The learner to recall the CO 2
movements in CI engines principles of air flow
movements and then
explain the air flow
movements for CI engines
11 Explain the Splash Remember — CO 2
lubrication system with the
diagram
12 Explain the carburettor Remember — CO 2
working principle with
diagram

Page 8
13 What are the types of fuel Understand The learner to recall the CO 2
injection systems? Explain principles of injection
anyone with a neat sketch? systems and then explain
the fuel injection systems in
detail.
14 Explain a two stroke cycle Understand The learner to recall the CO 2
engine from a 4 stroke cycle principles of IC engine and
engine? then explain the 4-Stroke
and 2-stroke engine.
15 Explain the Pressure feed Understand The learner to recall the CO 2
system with a diagram? principles of Pressure feed
system and then explain the
process in Pressure feed
system in IC engine.
16 In what respect four-stroke Apply The learner to recall the CO 2
diesel cycle (compression principles of various IC
Ignition) engine differs from engines and compare the
four stroke cycle spark 2-stroke and 4-stroke engine
ignition engine? then Apply to the industrial
applications used with
respect to 2 and 4-stroke
engine.
17 What do you mean by Understand The learner to recall the CO 2
Pre-ignition? How can it be principles of pre-ignition
detected? and then explain the
process of pre-ignition in IC
engine and how to detect it.
18 Explain the difference Understand The learner to recall the CO 2
between Pre-ignition, principles of ignition and
auto-ignition and then explain the various
detonation. types of ignition system.
19 What is meant by ignition Remember — CO 2
delay? Explain the steps in
SI engines ignition delay?
20 Why do we feel the Remember — CO 2
necessity of cooling an IC
engine? Explain briefly the
following methods of cooling
IC engines: Air-cooling and
Liquid - cooling?
PART C-SHORT ANSWER QUESTIONS

Page 9
1 What is the normal Understand The learner to recall the CO 2
combustion and abnormal concepts of combustion in
combustion in SI engine? SI engine then explain
normal combustion and
abnormal combustion.
2 What is called flame front Remember — CO 2
and flame velocity?
3 What is knocking in both SI Understand The learner to recall the CO 2
and CI engines? concept of Knocking and
explain the effects of
knocking in an SI and CI
engine.
4 What decides severity of Understand The learner to recall the CO 2
knocking in both SI and CI concept of Knocking and
Engines? explain the effects of
knocking in an SI and CI
engine.
5 What is pre ignition and Remember — CO 2
optimum ignition timing?
6 What is ignition delay Understand The learner to recall the CO 2
period? concepts of ignition delay
and explain the ignition
delay period in IC engine
7 Define suction induced swirl Remember — CO 2
and combustion induced
swirl?
8 What is mixture strength? Understand The learner to recall the CO 2
How it influences the concepts of the fuel mixture
combustion? process and explain the
process of mixing of fuel
consumption
9 What are anti-knock Remember — CO 2
agents? Main difference
between working of
anti-knock agent in SI and
CI Engines?
10 What is a combustion Remember — CO 2
chamber? What are the
different combustion zones
in combustion chamber?

Page 10
11 What are the types of Understand The learner to recall the CO 2
ignition systems concept of ignition delay of
CI engine and then explain
the different types of
ignition systems.
12 Give the two methods of Remember — CO 2
cooling systems?
13 List the properties of Remember — CO 2
lubricants?
14 Explain various factors Understand The learner to recall the CO 2
affecting normal combustion concepts of combustion in
in SI system? SI engine then explain
normal combustion and
abnormal combustion.
15 What are the properties of Understand The learner to recall the CO 2
liquid fuels? concepts of fuels in IC
engine then explain
properties of liquid fuels.
16 What are the tests for Understand The learner to recall the CO 2
identifying pre-ignition? ignition systems then
explain various tests
involved in this process.
17 Differentiate auto ignition Understand The learner to recall the CO 2
and detonation ignition systems then
explain various tests
involved in this process..
18 What are the effects of Remember — CO 2
detonation?
19 How to control detonation? Remember — CO 2
20 How to control detonation Remember — CO 2
and scavenging?
MODULE III
TESTING AND PERFORMANCE,COMPRESSORS
PART-A PROBLEM SOLVING AND CRITICAL THINKING QUESTIONS
1 The data recorded during Apply The learner to recall the two CO 3
the trial of a two stroke stroke diesel engine then
diesel engine are as follows: explain various parameters
Engine speed =1500rpm involved in this process and
Load on brakes =110kg Apply it to different
brake arm parameters to find out the
=900mmDetermine the solution of brake power.
following: (a) Brake torque,
(b) Power available at the
brakes of the engine.

Page 11
2 During testing a two stroke, Apply The learner to recall the CO 3
diesel engine with rope concept two stroke, diesel
brake dynamometer, the engine process and then
following were recorded: explains the working
Engine speed =700rpm concept of
Diameter of brake drum dynamometer and Apply
=600mm Diameter of rope them to find out Power
=50mm Dead load on the
brake drum=35kg Spring
balance reading =4.5kg
Find the power available at
the brakes, in KW.
3 During the trial on a single Apply The learner to recall the two CO 3
cylinder, four stroke, diesel stroke diesel engine then
engine the following are explain various parameters
noted: Load on hydraulic involved in this process and
dynamometer=950N Apply it to different
Dynamometer constant parameters to find out the
=7500 Fuel used per hour = brake thermal efficiency.
10.5kg/hr Calorific values of
fuel =50000kJ/Kg Engine
speed =400rpm. Calculate
brake thermal efficiency of
the engine
4 An Otto cycle four stroke Apply The learner to recall the CO 3
gas engine has a cylinder Otto cycle four stroke gas
25cm in diameter and the engines then explain various
stroke of the piston is 40cm. parameters involved in this
It operates under the process and Apply it to
following conditions: Speed different parameters to find
=200rpm misfires per out the different powers.
minute =10 Mean effective
pressure=6.2kg/cm2
Mechanical efficiency
=80Determine (a) IHP, (b)
BHP and (c) Friction horse
power.
5 Calculate the volumetric Apply The learner to recall the two CO 3
efficiency of a petrol engine stroke diesel engine then
of 6cm bore and 9cm stroke explain various parameters
if each cylinder sucks involved in this process and
0.0025kg of charge during Apply it to different
suction stroke. Assume R as parameters to find out the
29.27. volumetric efficiency.

Page 12
6 A four cylinder engine Apply The learner to recall the two CO 3
running at 1200rpm stroke diesel engine then
developed 25.3BHP. The explain various parameters
average torque when one involved in this process and
cylinder was cut out was Apply it to different
10.5kg-m. Determine the parameters to find out the
indicated thermal efficiency, indicated thermal efficiency.
if the calorific value of the
fuel used is 10000kcal/kg,
and the engine uses 0.25kg
of petrol per BHP hour.
7 In the Morse test with a Analyze The learner to recall the two CO 3
four cylinder four stroke stroke diesel engine then
petrol engine, the following explain various parameters
data were obtained for a involved in this process and
particular setting and speed. Apply it to different
BHP with all cylinders parameters to find out the
working =32.0 BHP with volumetric efficiency and
No 1 cylinder cut off=21.6 Analyze the power
BHP with No 2 cylinder cut requirement and optimize it.
off=22.3 BHP with No 3
cylinder cut off=22.5 BHP
with No 4 cylinder cut
off=23.0 Estimate the IHP
of the engine and its
mechanical efficiency and
how do you optimize it.

Page 13
8 During the trial of a single Analyze The learner to recall the two CO 3
cylinder, four stroke oil stroke diesel engine then
engine, the following explain various parameters
observations were recorded: involved in this process ,
Bore and Stroke =300mm x Apply it to different
450mm Engine parameters to find out the
speed=220rpm Duration of volumetric efficiency and
trial =60minutesFuel Analyze the power
consumption requirement and optimize it.
=7.0kgCalorific valve of
fuel=45000kJ/kg Area of
indicator diagram
=320mm2Length of
indicator
diagram=60mmSpring
index=1.1bar/mm Net load
on brakes =130kgBrake
drum diameter
=1650kgTotal weight of
jacket cooling water
=500kgTemperature rise of
jacket cooling water=400
Temperature of exhaust
gases=300air Consump-
tion=300kgAssume specific
heat of exhaust gases=
1.004 kJ/kg K, specific heat
of water =4.185kJ/kg k and
room temperature =250C
Determine the following a
Power available at brakes.
b. Indicated power
developed, c. Mechanical
efficiency, d. Thermal
efficiency, e. Heat balance
sheet.

Page 14
9 The following readings are Analyze The learner to recall the two CO 3
observed during the trial of stroke diesel engine then
a single cylinder, four stroke explain various parameters
diesel engine. Fuel used per involved in this process and
hour=11kg;mass analysis of Apply it to different
fuel is carbon 85per, oxygen parameters to find out the
14per, non-combustibles volumetric efficiency and
1per;calorific value of fuel is Analyze the power
50000kJ/kg. The volumetric requirement and optimize it.
analysis of the exhaust
gases is carbon dioxide
8.5per, oxygen 10per, and
nitrogen 81.5per.
Temperature of exhaust
gases is 400c. Specific heat
of Exhaust gases is
1.05kJ/kg. Partial pressure
of steam in the exhaust
gases is 0.030bar.Ambient
temperature is
200c.Calculate the
percentage of heat carried
away by the exhaust gases.
10 During the trial on a single Apply The learner to recall the two CO 3
cylinder, four stroke, diesel stroke diesel engine then
engine the following are explain various parameters
noted: Load on hydraulic involved in this process and
dynamometer =950N Apply it to different
Dynamometer constant parameters to find out the
=5500 Fuel used per hour = brake thermal efficiency.
10.5kg/hr Calorific values of
fuel =20000kJ/Kg Engine
speed =400rpm. Calculate
brake thermal efficiency of
the engine.
PART B-LONG ANSWER QUESTIONS
1 Explain the Morse test to Understand The learner to recall the CO 3
fins the frictional power. concept of performance of
the engine and then explain
the various parameters
using morse test.

Page 15
2 What is William’s line and Apply The learner to recall the CO 3
how do you measure concept of performance of
frictional power using this. the engine parameters and
then explain William’s line
in this process and Apply to
measure frictional power
3 Discuss different types of Understand The learner to recall the CO 3
dynamometers. principle of dynamometers
then explain various types
of dynamometers involved
in this process.
4 Write short notes on Understand The learner to recall the CO 3
Exhaust gas analysis. concept of performance of
the engine and then explain
Exhaust gas analysis
concept.
5 Define the following terms: Understand The learner to recall the CO 3
Indicated Power, Brake concept of performance of
power, Friction Power, the engine and then explain
Mechanical efficiency, Mean the various testing
effectiveness. parameters.
6 What is the significance of Remember — CO 3
heat balance sheet? Discuss
the procedure to draw heat
balance sheet for CI engine.
7 Explain the phenomenon of Understand The learner to recall the CO 3
knocking in IC engines? concept of Knocking and
What are the different explain the effects of
factors influencing the knocking in IC engine.
knocking?
8 Define the following terms: Understand The learner to recall the CO 3
brake thermal efficiency, concept of performance of
Mechanical efficiency, engine the engine and then explain
size, volumetric efficiency the various testing
parameters.
9 Define the following terms: Understand The learner to recall the CO 3
Brake power, Brake Specific concept of performance of
Fuel Consumption, Friction the engine and then explain
Power, Mechanical the various testing
efficiency, Mean parameters.
effectiveness.

Page 16
10 Explain the phenomenon of Understand The learner to recall the CO 3
knocking in SI engines? concept of Knocking and
What are the different explain the effects of
factors influencing the knocking in IC engine.
knocking?
11 Explain multistage Understand The learner to recall the CO 4
compression with a neat principle of compressor then
sketch explains multistage
compression.
12 Derive volumetric efficiency Understand The learner to recall the CO 4
of air compressor principle of compressor then
explains volumetric
efficiency of air compressor.
13 Classify various compressors Understand The learner to recall the CO 4
and explain in detail. principle of compressor then
explains various
compressors in detail.
14 What is the condition for Understand The learner to recall the CO 4
maximum efficiency in principle of compressor then
multistage compression? explains maximum efficiency
in multistage compression.
15 Enumerate the applications Apply The learner to recall the CO 4
of compressed air? How air principle of air compressor
compressors classified? then explains working of air
compressor and classify and
Apply to industrial
applications
16 Classify dynamic Apply The learner to recall the CO 4
compressors. Explain the principle of air compressor
working of axial compressor then explains working of
and its applications. axial compressor and
classifies and Apply to
industrial applications.
17 State how the air Remember — CO 4
compressors are classified?
18 Explain the working of a Understand The learner to recall the CO 4
reciprocating compressor principle of compressor then
explains working of a
reciprocating compressor.
19 Classify rotary compressors. Remember — CO 4
Explain the working of a
rotary compressor

Page 17
20 Classify dynamic Remember — CO 4
compressors. Explain the
working of a centrifugal
compressor.
PART C-SHORT ANSWER QUESTIONS
1 Define brake power? Remember — CO 3
2 Define mechanical Remember — CO 3
efficiency?
3 List the devices used to Remember — CO 3
measure the cylinder
pressure.
4 What is an indicated power? Understand The learner to recall the CO 4
principle of LOM then
explain various parameters
involved in this process.
5 What are the various losses Remember — CO 4
of IC Engine?
6 How do you determine heat Remember — CO 4
losses explain with sankey
diagram?
7 Define clearance ratio.. Remember — CO 3
8 What is specific fuel Remember — CO 3
consumption?
9 Define volumetric efficiency? Remember — CO 3
10 What is the use of heat Understand The learner to recall the CO 4
balance sheet of an engine principle of engine
parameters then explains
the type of heat balance
sheet of an engine.
11 Classify positive Understand The learner to recall the CO 4
displacement compressors. principle of compressor then
explains various positive
displacement compressors.
12 State the basic function of Remember — CO 4
an air dryer in a compressor.
13 Write the capacity range of Remember — CO 4
a vertical type reciprocating
compressors.
14 Define a compressor. Remember — CO 4

Page 18
15 Classify non-positive Understand The learner to recall the CO 4
displacement compressors principle of compressor then
explains various
non-positive displacement
compressors.
16 Mention the primary Understand The learner to recall the CO 4
element of a centrifugal principle of compressor then
compressor. explains primary centrifugal
compressor.
17 Classify different types of Understand The learner to recall the CO 4
compressors. principle of compressor then
explains different types of
compressors.
18 When are the rotary Remember — CO 4
compressors employed?
19 Classify rotary type Remember — CO 4
compressors.
20 Mention the primary Remember — CO 4
element of an axial
compressor.
MODULE IV
ROTARY AND AXIAL CENTRIFUGAL COMPRESSORS
PART-A PROBLEM SOLVING AND CRITICAL THINKING QUESTIONS
1 An air compressor takes in Analyze The learner to recall the two CO 5
air at 1 bar and 20 0 C and stroke diesel engine then
compresses it according to explain various parameters
law pv 1.2 = constant .It is involved in this process and
then delivered to a receiver Apply it to different
at a constant pressure of 10 parameters to find out the
bar. R=0.287 KJ/Kg volumetric efficiency and
Determine: (i) Temperature Analyze the work done and
at the end of compression optimize it.
(ii) Work done and heat
transferred during
compression per kg of air.

Page 19
2 A single–stage, Analyze The learner to recall the two CO 5
double-acting compressor stroke diesel engine then
has a free air delivery explain various parameters
(FAD) of 14 m3/min. involved in this process and
measured at 1.013 bar and Apply it to different
150C. The pressure and parameters to find out the
temperature in the cylinder volumetric efficiency and
during induction are 0.95 Analyze the power
bar 320 C. The delivery requirement and optimize it.
pressure is 7 bar and index
of compression and
expansion, n=1.3.The
clearance volume is 5 per of
the swept volume. Calculate
(i) Indicated power required
(ii) Volumetric efficiency.
3 Air at 103 K Pa and 27 0C Analyze The learner to recall the two CO 5
is drawn in LP cylinder of a stroke diesel engine then
two stage air compressor explain various parameters
and is isentropic ally involved in this process and
compressed to 700 KPa. Apply it to different
The air is then cooled at parameters to find out the
constant pressure to 37 0C volumetric efficiency and
in an intercooler and is then Analyze the power
again compressed isentropic requirement and optimize it.
ally to 4 MPa in the H.P
cylinder, and is then
delivered at this pressure
Determine the power
required to run the
compressor if it has to
deliver 30 m3 of air per
hour measured at inlet
conditions.
4 A roots blower compresses Apply The learner to recall the two CO 5
0.08 m3 of air from 1.0 bar stroke diesel engine then
to 1.5 bar per revolution explain various parameters
.Calculate the compressor involved in this process and
efficiency. Apply it to different
parameters to find out the
compressor efficiency

Page 20
5 A centrifugal compressor Analyze The learner to recall the two CO 5
delivers 16.5 kg/s of air with stroke diesel engine then
a total head pressure ratio explain various parameters
of 4:1 .The speed of the involved in this process and
compressor is 1500 RPM. Apply it to different
Inlet total head temperature parameters to find out the
is 200 C, slip factor 0.9 volumetric efficiency and
Power input factor 1.04 and Analyze the power
80 per isentropic efficiency. requirement and optimize it.
Calculate: Overall diameter
of the impeller ii. Power
input
6 A multi stage axial flow Analyze The learner to recall the two CO 5
compressor delivers 20 stroke diesel engine then
kg/sec of air. The inlet explain various parameters
stagnation condition is 1 involved in this process and
bar and 17 0 C. The power Apply it to different
consumed by the compressor parameters to find out the
is 4350 kW .Calculate (i) volumetric efficiency and
The delivery pressure Analyze the power
(ii)Number of stages (iii) requirement and optimize it.
Overall isentropic efficiency
of the compressor.
7 An axial flow compressor Apply The learner to recall the two CO 5
with an overall isentropic stroke diesel engine then
efficiency of 85 per draws explain various parameters
air at 200 C and compresses involved in this process and
it in the pressure ratio Apply it to different
4:1.The mean blade speed parameters to find out the
and flow velocity are no of stages.
constant throughout the
compressor. Assuming 50
per reaction blading and
taking blade velocity as 180
m/sec. and work input
factor as 0.82.calculate (i)
Flow velocity (ii) Number of
stages.

Page 21
8 A Centrifugal compressor Analyze The learner to recall the two CO 5
used as a super charger for stroke diesel engine then
aero-engines handles 150 explain various parameters
kg/min of air. The suction involved in this process and
pressure and temperature Apply it to different
are 1bar and 290K. the parameters to find out the
suction velocity is 80 m/s. volumetric efficiency and
after compression in the Analyze the power
impeller the conditions are requirement and optimize it.
1.5bar 345K and 220 m/s.
Calculate: a) Isentropic
efficiency b) power required
to drive the compressor c)
The overall efficiency of the
unit. It may be assumed
that K.E. gained in the
impeller is entirely
converted into pressure in
the diffuser.
9 Air at a temperature of Apply The learner to recall the two CO 5
300K flows in a centrifugal stroke diesel engine then
compressor running at explain various parameters
18000 r.p.m. Isentropic involved in this process and
total head efficiency= 0.76, Apply it to different
outer diameter of blade parameters like static
tip= 550mm, slip factor= pressure.
0.82. calculate A) the
temperature rise of air
passing through the
compressor B) the static
pressure ratio.
10 A multi stage axial flow Apply The learner to recall the two CO 5
compressor delivers 20 stroke diesel engine then
kg/sec of air. The inlet explain various parameters
stagnation condition is 1 involved in this process and
bar and 190 C. The power Apply it to different
consumed by the compressor parameters to find out the
is 5350 kW .Calculate (i) compressor efficiency
The delivery pressure
(ii)Number of stages (iii)
Overall isentropic efficiency
of the compressor

Page 22
 PART B-LONG ANSWER QUESTIONS
1 State how the air Understand The learner to recall the CO 5
compressors are classified. concepts of air compressor
then explains the
classification of air
compressors.
2 Explain the working of Understand The learner to recall the CO 5
roots blower. concept of blower then
explains the working of
roots blower.
3 Explain the working of vane Understand The learner to recall the CO 5
blower concept of blower process
and then explain the
working of vane blower.
4 What is rotary compressor? Understand The learner to recall the CO 5
How are they classified? concept of rotary
compressor and then
explain the working of
rotary compressor and its
classification.
5 Draw the velocity diagram Apply The learner to recall the CO 5
of an axial flow compressor. concept of compressor and
then explain the working of
axial flow compressor and
apply the concept to
velocity diagram.
6 What do you mean by Analysis The learner to recall the CO 5
multistage compression? concept of compressor and
And state its advantages then explain the different
and applications? stages of compression and
apply multi stage
compressor process and
analyze the technology to
industrial applications.
7 Draw velocity diagrams of Apply The learner to recall the CO 5
centrifugal compressors. concept of compressor and
then explain the working of
centrifugal compressor and
apply the concept to
velocity diagram.

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8 Compare between Understand The learner to recall the CO 5
reciprocating and rotary concept of rotary and
compressors. reciprocating compressor
and then compare the
working of rotary
compressor.
9 Compare between axial flow Understand The learner to recall the CO 5
and centrifugal compressors. concept of axial flow and
centrifugal compressor and
then compare the working
of axial flow and centrifugal
compressor.
10 Discuss of working Understand The learner to recall the CO 5
centrifugal compressors. concept of compressor and
then explain the working of
centrifugal compressor.
11 Describe with a neat sketch Understand The learner to recall the air CO 5
the construction and compressor process and
working of a single-stage explain the working of
single-acting reciprocating single-stage single-acting
air compressor. reciprocating air
compressor.
12 Describe briefly an axial Understand The learner to recall the CO 5
flow compressor. concept of compressor and
then explain the working of
axial flow compressor.
13 Write short notes on a) Understand The learner to recall the CO 5
clearance in compressors b) concepts of air compressor
free air delivered and then explains the
displacement c)compressor classification of air
performance compressors.
14 Explain with a neat sketch Apply The learner to recall the CO 5
actual p-V diagram for a concepts of air compressor
single stage compressor. then explains the working of
single stage compressor
apply it to p-V diagram
15 What is a centrifugal Understand The learner to recall the CO 5
compressor? How does it concept of compressor and
differ from an axial flow then compare the
compressor? centrifugal and axial flow
compressor.

Page 24
16 Write short notes on a) Understand The learner to recall the CO 5
control of compressors b) concepts of air compressor
intercooler c)compressed air then explains the
motors parameters of air
compressors.
17 Explain the working of a Understand The learner to recall the CO 5
reciprocating compressor concepts of air compressor
with its sectional view then explains the working of
diagram. reciprocating compressor
with sectional view diagram.
18 Explain with a neat sketch Understand The learner to recall the air CO 5
actual p-V diagram for a compressor process and
two- stage compressor. explain the working of
two-stage compressor.
19 Define the following Apply The learner to recall the CO 5
efficiencies as applied to concepts of air compressor
reciprocating air then explains the
compressors: a) compressor parameters of reciprocating
Efficiency b) Isothermal air compressors and applies
Efficiency c) Adiabatic it to find out the Efficiency.
Efficiency d) Mechanical
Efficiency
20 Mention the advantages and Remember — CO 5
disadvantages of multi stage
compression.
PART C-SHORT ANSWER QUESTIONS
1 What is volumetric Understand The learner to recall the CO 5
efficiency in case of principle of compressor then
compressor? explains volumetric
efficiency in case of
compressor.
2 Define slip factor? Remember — CO 5
3 Define pressure coefficient. Remember — CO 5
4 What is the difference Remember — CO 5
between reciprocating and
rotary compressors?
5 What is stalling? Remember — CO 5
6 Draw p-v and T-S diagram Remember — CO 5
of a MULTI stage
reciprocating compressors?
7 What is the function of an Remember — CO 5
intercooler in compressors?
8 What are rotary Remember — CO 5
compressors?

Page 25
9 What is the difference Remember — CO 5
between positive
displacement and
non-positive displacement
compressors?
10 What do you mean by Remember — CO 5
Choking?
11 Specify the function of a Remember — CO 5
diffuser.
12 Mention the primary Remember — CO 5
component of a rotary
compressor.
13 Write the function of a rotor Remember — CO 5
in rotary compressors.
14 Define stage in a Axial flow Understand The learner to recall the CO 5
Compressor. principle of compressor then
explain various stages of
Axial flow Compressor.
15 Mention the definition of Remember — CO 5
‘Degree of Reaction”.
16 Write the formula for Blade Remember — CO 5
loading coefficient in a Axial
flow compressor.
17 State or define Volumetric Remember — CO 5
efficiency of a reciprocating
compressor.
18 How an Air compressor may Remember — CO 5
be controlled?
19 Why the clearance volume Remember — CO 5
of a air compressor is kept
minimum?
20 Mention the types of rotary Remember — CO 5
compressors.

Page 26
 MODULE V
REFRIGERATION
PART-A PROBLEM SOLVING AND CRITICAL THINKING QUESTIONS
1 An air refrigeration system Analyze The learner to recall the air CO 6
operates between 1 MPa refrigeration system then
and 100 K Pa is required to explain various parameters
produce a cooling effect of involved in this process and
2000 KJ/min. Temperature Apply it to different
of the air leaving the cold parameters to find out the
chamber is -5 0 C and at COP and Analyze the power
leaving the cooler is 30 0 C. requirement and optimize it.
Neglect losses and clearance
in the compressor and
expander determine (i) Mass
of air circulated per min
(ii) Compressor work
,expander work, cycle work
(iii) COP and power in KW
required
2 28 tonnes of ice from and at Analyze The learner to recall the air CO 6
0 0 C is produced per day in refrigeration system then
an ammonia refrigerator. explain various parameters
The temperature range in involved in this process and
the compressor is from 25 Apply it to different
0C to -15 0C.The vapour is parameters to find out the
dry and saturated at the COP and Analyze the power
end of compression and an requirement and optimize it.
expansion valve is used.
Assuming a co efficient of
performance of 62 per of the
theoretical, calculate the
power required to drive the
compressor. take latent heat
of ice is 335 KJ/kg.

Page 27
3 A refrigerator operating on Analyze The learner to recall the air CO 6
stand vapour compression refrigeration system then
cycle has a coefficient explain various parameters
performance of 6.5 and is involved in this process and
driven by a 50 KW Apply it to different
compressor. The enthalpies parameters to find out the
of saturated liquid and COP and Analyze the power
saturated vapour refrigerant requirement and optimize it.
at the operating condensing
temperatures of 35 0 C are
62.55 KJKg and 201.45
KJKg. The standard
refrigerant vapour leaving
evaporator has an enthalpy
of 187.53kJkg. Find the
refrigeration temperature at
compressor discharge. The
Cp of refrigerant vapour
may be taken to be 0.6155
kJkg.0C.
4 In a simple vapour Analyze The learner to recall the air CO 6
compression cycle the piston refrigeration system then
displacement volume for explain various parameters
compressor is 1.5 liters per involved in this process and
stroke and its volumetric Apply it to different
efficiency is 80 per.The parameters to find out the
speed of compressor is 1600 COP and Analyze the power
rpm. Find the power rating requirement and optimize it.
of compressor and
refrigerating effect.
5 Ice is formed at 0°C from Analyze The learner to recall the air CO 6
water at 20°C. The refrigeration system then
temperature of the brine is explain various parameters
– 8°C. Find out the kg of ice involved in this process and
formed per kWh. Assume Apply it to different
that the refrigeration cycle parameters to find out the
used is perfect reversed COP and Analyze the power
Carnot cycle. Take latent requirement and optimize it.
heat of ice as 335 kJ/kg.

Page 28
6 A refrigerating machine of 6 Analyze The learner to recall the air CO 6
tonnes capacity working on refrigeration system then
Bell-Coleman cycle has an explain various parameters
upper limit of pressure of involved in this process and
5.2 bar. The pressure and Apply it to different
temperature at the start of parameters to find out the
the compression are 1.0 bar COP and Analyze the power
and 16°C respectively. The requirement and optimize it.
compressed air cooled at
constant pressure to a
temperature of 41°C enters
the expansion cylinder.
Assuming both expansion
and compression processes
to be adiabatic with Y= 1.4,
calculate : (i)Co-efficient of
performance. (ii)Quantity
of air in circulation per
minute. (iii)Piston
displacement of compressor
and expander. (iv)Bore of
compressor and expansion
cylinders. The unit runs at
240 r.p.m. and is
double-acting. Stroke length
= 200 mm. (v)Power
required to drive the unit
For air take Y= 1.4 and
cp= 1.003 kJ/kg K.
7 A simple vapour Analyze The learner to recall the air CO 6
compression plant produces refrigeration system then
5 tonnes of refrigeration. explain various parameters
The enthalpy values at inlet involved in this process and
to compressor, at exit from Apply it to different
the compressor, and at exit parameters to find out the
from the condenser are COP and Analyze the power
183.19, 209.41 and 74.59 requirement and optimize it.
kJ/kg respectively.
Estimate : (i)The
refrigerant flow rate, (ii)The
C.O.P., (iii)The power
required to drive the
compressor, and (iv)The
rate of heat rejection to the
condenser.

Page 29
8 A vapour compression heat Analyze The learner to recall the air CO 6
pump is driven by a power refrigeration system then
cycle having a thermal explain various parameters
efficiency of 25per. For the involved in this process and
heat pump, refrigerant-12 is Apply it to different
compressed from saturated parameters to find out the
vapor at 2.0 bar to the COP and Analyze the power
condenser pressure of 12 requirement and optimize it.
bar. The isentropic
efficiency of the compressor
is 80per.Saturated liquid
enters the expansion valve
at 12 bar. For the power
cycle 80per of the heat
rejected by it is transferred
to the heated space which
has a total heating
requirement of 500 kJ/min.
Determine the power input
to the heat pump
compressor. The following
data for refrigerant-12may
be used :
9 A refrigeration machine is Analyze The learner to recall the air CO 6
required to produce i.e., at refrigeration system then
0°C from water at 20°C. explain various parameters
The machine has a involved in this process and
condenser temperature of Apply it to different
298 K while the evaporator parameters to find out the
temperature is268 K. The COP and Analyze the power
relative efficiency of the requirement and optimize it.
machine is 50per and 6 kg
of Freon-12 refrigerant is
circulated through the
system per minute. The
refrigerant enters the
compressor with a dryness
fraction of0.6. Specific heat
of water is 4.187 kJ/kg K
and the latent heat of ice is
335 kJ/kg. Calculate the
amount of ice produced on
24 hours.

Page 30
10 An air refrigeration system Analyze The learner to recall the air CO 6
operates between 1 MPa refrigeration system then
and 200 K Pa is required to explain various parameters
produce a cooling effect of involved in this process and
3000 KJ/min. Temperature Apply it to different
of the air leaving the cold parameters to find out the
chamber is -5 0C and at COP and Analyze the power
leaving the cooler is 40 0 C. requirement and optimize it.
Neglect losses and clearance
in the compressor and
expander determine (i) Mass
of air circulated per min (ii)
Compressor work ,expander
work ,cycle work(iii) COP
and power in KW required
PART B-LONG ANSWER QUESTIONS
1 Describe a simple vapour Understand The learner to recall the CO 6
compression cycle giving concepts of refrigeration
clearly its flow diagram. system and then explain the
working of simple vapour
compression cycle.
2 Show the vapour Apply The learner to recall the CO 6
compression cycle on T-S concepts of refrigeration
diagram when the vapour is system and then explain the
dry saturated, super-heated. working of simple vapour
compression cycle and apply
to draw a T-S diagram
when the vapour is dry
saturated, super-heated.
3 What are the factors that Understand The learner to recall the CO 6
affect the performance of a concepts of refrigeration
vapour compression system system and then explain the
and explain? working of simple vapour
compression cycle.
4 What are desired properties Remember —- CO 6
of refrigerants?
5 Explain with neat sketch Understand The learner to recall the CO 6
the working of a vapour concepts of refrigeration and
absorption system. then explain the working of
a vapour absorption system.

Page 31
6 Compare between vapour Understand The learner to recall the CO 6
compression and vapour concepts of refrigeration
absorption systems. process and then compare
between vapour compression
and vapour absorption
systems.
7 Explain air refrigeration Remember —- CO 6
system.
8 Explain reversed Carnot Understand The learner to recall the CO 6
cycle on T-S diagram concepts of refrigeration
technology and then explain
reversed Carnot cycle and
apply it to form a T-S
diagram
9 What are the different Understand The learner to recall the CO 6
components of vapour concepts of vapour
compression system and compression system process
explain with neat sketch and then explain the
working with a neat sketch.
10 Classify and explain Understand The learner to recall the CO 6
refrigerants. concepts of refrigerants and
then explain different types
of refrigerants.
11 Differentiate clearly between Understand The learner to recall the CO 6
open and closed air concepts of air refrigeration
refrigeration systems. systems and then compare
between open and closed air
refrigeration systems.
12 State merits and demerits of Understand The learner to recall the CO 6
‘vapour compression system’ concepts of air refrigeration
over ‘air refrigeration systems and vapour
system’. compression system and
then compare merits and
demerits.
13 Enumerate the properties Remember —- CO 6
and uses of commonly used
refrigerants.
14 Write the important Apply The learner to recall the CO 6
refrigeration applications. concepts of refrigeration and
Elements of refrigeration then explain the working
system. process and apply its
application in industries.

Page 32
15 State the functions of the Understand The learner to recall the CO 6
following parts of a simple concepts of refrigeration
vapour compression system: processes and then explain
compressor, condenser, different parameters under
expansion valve and it.
evaporator.
16 Give the comparison UnderstandThe learner to recall the CO 6
between a vapour concepts of air refrigeration
compression system and a systems and vapour
vapour absorption system. compression system and
then compare vapour
compression system and a
vapour absorption system.
17 Briefly explain pressure Apply The learner to recall the CO 6
enthalpy chart. concepts of refrigeration and
then explain the working of
a vapour absorption system
and apply it to pressure
enthalpy chart.
18 Explain practical vapour Understand The learner to recall the CO 6
absorption system. concepts of refrigeration and
then compare the working
of a vapour absorption
system with practical.
19 Write the functions of parts Understand The learner to recall the CO 6
of a simple vapour concepts of refrigeration
compression system. processes and then explain
different parameters under
it.
20 Show the vapour Understand The learner to recall the CO 6
compression cycle on T-S concepts of refrigeration
diagram when the vapour is technology and then explain
super-heated and wet after reversed Carnot cycle and
compression. apply it to form a T-S
diagram
PART C-SHORT ANSWER QUESTIONS
1 Define refrigeration? Remember — CO 6
2 Define (i) actual COP (ii) Remember — CO 6
Theoretical COP.
3 What is the difference Remember — CO 6
between wet compression
and dry compression?
4 Write short notes on p-h Remember — CO 6
chart.

Page 33
 5 What is unit of refrigeration Remember — CO 6
6 What is the function of Remember — CO 6
capillary tube in vapour
compression refrigeration
system?
7 What are the different Remember — CO 6
components of vapour
compression system
8 What is the effect of sub Remember — CO 6
cooling
9 State demerits of air Remember — CO 6
refrigeration system
10 What is the function of Remember — CO 6
Expansion valve?
11 Define (i) COP(iii) Relative Remember — CO 6
COP
12 Mention a reversed heat Remember — CO 6
engine cycle and its
function.
13 Write the operations in a Remember — CO 6
vapour refrigeration cycle.
14 Why is wet compression not Remember — CO 6
preferred.
15 Define refrigerating system? Remember — CO 6
16 Specify the main Understand The learner to recall the CO 6
characteristic feature of an concepts of refrigeration and
air refrigeration system then explain the
characteristic feature of an
air refrigeration system.
17 State elements of Remember — CO 6
refrigerating system.
18 Why an analyzer-rectifier Remember — CO 6
combination is used in
absorption refrigeration
cycle.
19 State merits of air Remember — CO 6
refrigeration system.
20 Mention the Effect of Remember — CO 6
superheating.

Course Coordinator: HOD ME

Dr. K. Ch Apparao, Associate Professor

Page 34