This document describes a thermo-structural analysis of pistons in an internal combustion engine. Four piston designs - flat, dome, cup, and bowl - were modeled in CATIA and analyzed in ANSYS. Thermal analysis determined temperature distributions and structural analysis determined stress and deformation. The flat and dome pistons made of aluminum alloy AL4032 performed best with lowest stresses of 80.11 MPa and 80.24 MPa respectively and lowest deformations of 0.02 mm and 0.01 mm. Therefore, the flat and dome piston designs provided the most optimal thermal and structural performance.

1. VARDHAMAN COLLEGE OF ENGINEERING, HYDERABAD
Autonomous institute affiliated to JNTUH
DEPARTMENT OF MECHANICAL ENGINEERING
Under the Guidence of
Dr. Mukul Shrivastava
Professor
Department of mechanical Engineering
ICAMS-2021
Title: THERMO- STRUCTURAL ANALYSIS OF PISTON IN A COMPRESSION
IGNITION ENGINE
S.NO NAME
1 Dr. Mukul Shrivastava
2 M.Jeevana
3 Venkata Sasi Priya Reedi
4 MD. Sameer
5 L. Lakshmana Rao

2. OUTLINE
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• Abstract
• Introduction
• Objective of the project work
• Literature review
• Research gap
• Proposed methodology
• Types of piston models
• Thermal analysis of pistons
• Expected outcomes
• References

3. Abstract
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DEPARTMENT OF MECHANICAL ENGINEERING
The piston is a component of the internal combustion engine. The
main function of the piston is to transform the pressure generated
by the burning air-fuel mixture into force, acting on the crankshaft
In IC engine, Piston is one of the most important and complex part.
With increasing power and performance of engine, higher thermal
load and the thermal stresses are acting on piston, thereby,
decreasing its life time. So It is necessary to maintain Piston in
good condition in order to maintain the proper functioning of the
engine. Piston mainly fails due to thermal Conditions. So Its is
essential to evaluate the piston with different crown shapes and find
the thermal and structural performance.
In this paper 4 different types of piston is developed using CATIA –
V5 a powerful 3D Modelling tool and structural and thermal
analysis will be done by ANSYS using different materials to find
out the temperature and thermal stress distribution.

4. INTRODUCTION
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DEPARTMENT OF MECHANICAL ENGINEERING
• Piston is one of the mechanical component which was invented by
German scientist Nicholas August Otto in year 1866.
• A piston is a component of reciprocating IC-engines. It is the
moving component that is contained by a cylinder and is made
gas-tight by piston rings. The purpose of the piston is to
provide a means of conveying the expansion of gases to the
crankshaft via connecting rod, The piston acts as a movable end
of the combustion chamber Piston is essentially a cylindrical plug
that moves up & down in the cylinder It is equipped with piston
rings to provide a good seal between the cylinder wall.
Functions of Piston
• To reciprocate in the cylinder as a gas tight plug causing suction,
Compression, expansion, and exhaust strokes.

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DEPARTMENT OF MECHANICAL ENGINEERING
• To receive the thrust generated by the explosion of the gas in the
cylinder
• And transmit it to the connecting rod.
• To form a guide and bearing to the small end of the connecting rod
and to take the side thrust due to obliquity of the rod.
Factors Considered For Proper Functioning Of Piston :
• The piston should have enormous strength and heat resistance
properties to withstand gas pressure and inertia forces. They
should have minimum weight to minimize the inertia forces.
• The material of the piston should have good and quick dissipation
of heat from the crown to the rings and bearing area to the cylinder
walls. It should form an effective gas and oil seal.

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DEPARTMENT OF MECHANICAL ENGINEERING
• Material of the piston must possess good wearing qualities, so that
the piston is able to maintain sufficient surface-hardness unto the
operating temperatures.
• Piston should have rigid construction to withstand thermal,
mechanical distortion and sufficient area to prevent undue wear. It
has even expansion under thermal loads so should be free as
possible from discontinuities.

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DEPARTMENT OF MECHANICAL ENGINEERING
PISTON PARTS:

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DEPARTMENT OF MECHANICAL ENGINEERING
Piston Head or Crown :
• The piston head or crown is designed keeping in view the
following two main considerations, i.e.
• It should have adequate strength to withstand the straining action
due to pressure of explosion inside the engine cylinder, and It should
dissipate the heat of combustion to the cylinder walls as quickly as
possible. On the basis of first consideration of straining action, the
thickness of the piston head is determined by treating it as a flat
circular plate of uniform thickness, fixed at the outer edges and
subjected to a uniformly distributed load due to the gas pressure over
the entire Cross-section.
Piston Rings :The piston rings are used to impart the necessary
radial pressure to maintain the seal between the piston and the
cylinder bore. These are usually made of grey cast iron or alloy cast
iron because of their good wearing properties and also they retain
spring characteristics even at high temperatures.

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DEPARTMENT OF MECHANICAL ENGINEERING
The piston rings are of the following two types:
• Compression rings or pressure rings, and
• Oil control rings or oil scraper.
• The compression rings or pressure rings are inserted in the
grooves at the top portion of the piston and may be three to
seven in number. These rings also transfer heat from the
piston to the cylinder liner and absorb some part of the piston
fluctuation due to the side thrust. The oil control rings or oil
scrapers are provided below the compression rings. These
rings provide proper lubrication to the liner by allowing
sufficient oil to move up during upward stroke and at the
same time scrap the lubricating oil from the surface of the
liner in order to minimize the flow of the oil to the
combustion chamber.

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DEPARTMENT OF MECHANICAL ENGINEERING
The compression rings are usually made of rectangular cross-section
and the diameter of the ring is slightly larger than the cylinder bore. A
part of the ring is cut- off in order to permit it to go into the cylinder
against the liner wall. The gap between the ends should be
sufficiently large when the ring is put cold so that even at the highest
temperature, the ends do not touch each other when the ring expands,
otherwise there might be buckling of the ring.
Major Force Acting over Piston :
• Due to explosion of fuel gases
• Due to compression of fuel gases
• Side wall friction and forces
• Thermal load
• Inertia force due to high frequency of reciprocation of piston
• Friction and forces at crank pin hole

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DEPARTMENT OF MECHANICAL ENGINEERING
Piston Application or uses:
The main application of the Piston is:
• Reduced inertia also improves the mechanical efficiency of the
engine.
• It compresses the fluid inside the cylinder hence increases the
pressure and temperature of the fluid inside the cylinder.
• It also provides the direction.
Piston Advantages:
The main advantages of the Piston are:
• Mechanical simplicity
• Flexibility and reliability
• Power to weight ratio
• Multi-fuel capability
• Low turbine operating temperature
• Less vibration and noise
• Less maintenance

12. Objective of the project
• There three objectives for this dissertation which is focus on
the piston for IC engine based on the finite element analysis.
The objectives are:
• To design 4 Different 3D models of piston for IC engine using
Catia V5.
• To investigate the maximum temperature distribution during
combustion using Steady state thermal analysis in Ansys.
• To investigate the maximum Thermal stress developed due to rise
in temperature and pressure using structural linear analysis using
Ansys.
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DEPARTMENT OF MECHANICAL ENGINEERING

13. Literature review
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DEPARTMENT OF MECHANICAL ENGINEERING
1. S.Srikanth Reddy, Dr. B. Sudheer Prem Kumar Did Thermal
Analysis and Optimization of I.C.Engine Piston Using Finite
Element Method
In this study, firstly, thermal analyses are investigated on a
conventional (uncoated) diesel piston, made of aluminum
silicon alloy for design 1 and design 2 parameters. Secondly,
thermal analyses are performed on piston, coated with
Zirconium material by means of using a commercial code,
namely ANSYS.
The effects of coating on the thermal behaviors of the pistons
are investigated. The finite element analysis is performed by
using computer aided design software. The main objective is to
investigate and analyze the thermal stress distribution of piston
at the real engine condition during combustion process.

14. Finally they concluded that Piston skirt may appear deformation at
work, which usually causes crack on the upper end of piston head.
Due to the deformation, the greatest stress concentration is caused on
the upper end of piston, the situation becomes more serious when the
stiffness of the piston is not enough, and the crack generally appeared
at the point A which may gradually extend and even cause splitting
along the piston vertical
•G.V.N. Kaushik did “Thermal and Static Structural Analysis on
Piston”
In this paper 3D model of piston is developed, structural and thermal
analysis is done by ANSYS using 5 different materials to find out the
temperature and thermal stress distribution, theoretically finding the
total heat flux and compare with the practical values of different
Piston Materials used.
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15. Finally they conclude that 42CrMo, Al-Si-C-12 undergo least
deformation under thermal loads and under mechanical loads Al-Si,
Al-Si-C-12 undergo least deformation. In case of Both Mechanical
and Thermal loads Al-Si-C-12 undergoes the least deformation. This
is mainly because while 42CrMo can withstand high temperatures but
cannot withstand high mechanical loads and in case of Al-Si, it can
withstand mechanical loads but cannot withstand high temperatures
like 42CrMo. In case of Al-Si-C-12, it can withstand both mechanical
and thermal loads. Hence Al-SI-C-12 undergoes least deformation
when both mechanical and thermal loads are applied. In conclusion
while designing a piston 42CrMo must be used to make the piston top
land because it is the surface of piston that directly comes in contact
with combustion of fuel and high temperatures and Al-Si-C-12 must
be used for piston skirt and rest of the piston.
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16. • A.R. Bhagat, Y. M. Jibhakate & Kedar Chimote did “Thermal
Analysis and Optimization of I.C. Engine Piston Using Finite
Element Method”
This paper describes the stress distribution of the seizure on piston
four stroke engine by using FEA. The main objectives is to
investigate and analyze the thermal stress distribution of piston at the
real engine condition during combustion process. The optimization is
carried out to reduce the stress concentration on the upper end of the
piston. With using computer aided design (CAD), Pro/ENGINEER
software the structural model of a piston will be developed.
Furthermore, the finite element analysis performed with using
software ANSYS. Finally they concluded that the stress distribution
on the pistonmainly depends on the deformation of piston. Therefore,
in order to reduce the stress concentration, the piston crown should
have enough stiffness to reduce the deformation.
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17. • Preeti Kumari, Anamika & Dr.H.C.Thakur did “Thermal
Analysis ofPiston of IC engine”
In this paper thermal stress distribution is shown for the simple piston
and reduced skirt length piston by changing the geometry of the
piston and it is suggested that which piston is better for same thermal
load. Steady state thermal analysis of the Piston have been done in
ANSYS 14.5. Finally they concluded,it can be demonstrated from the
above graphical data and figures that reduced skirt length piston
temperature reduced by 10-20’ as compared to simple piston while
boundary conditions are same .Similarly total heat flux variation also
reduced in case of reduced skirt length piston as compare to simple
piston. Piston failure occurs because of thermo-mechanical overload
by insufficient intercooling thermo-mechanical overload by over
fuelling
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18. Research gap
• Most of the papers discussed about piston materials and their
thermal performance only . They didn’t consider the structural
performance. Temperature differences between the Engine Head
and the piston cylinder have been a major role in inducing thermal
stresses and hence play a vital role in predicting the life of an IC
Engine.
• In this paper we focussed on thermal and structural evaluation of
different piston heads.
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19. Proposed methodology
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Create a 3D CAD model of the Piston for the specifications available.
Export the solid model into ANSYS Workbench and edit the model in Design
modeler environment if it is necessary
Create FEA Model and Apply the loads and BCs of the Piston model and run
the thermal analysis.
Convert the thermal model to structural model and apply the
structural/thermal loads and BCs.
Carryout the structural analysis for this model and tabulate the
results.

20. 20
Do the Same procedure for remaining models
Compare the stresses between 4 models and observe the
differences.

21. Types of piston design
• CATIA is a mechanical design software. It is a feature-based,
parametric solid modeling design tool that takes advantage of the
easy-to-learn Windows graphical user interface. You can create
fully associative 3D solid models, with or without constraints,
while using automatic or user-defined relations to capture the
design intent.
The four types of piston are designed using CATIA V5.
PISTON TYPES :
 FLAT TYPE PISTON .
 DOME TYPE PISTON.
 CUP TYPE PISTON.
 BOWL TYPE PISTON.
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22. Catia Introduction
• CATIA is a mechanical design software. It is a feature-based,
parametric solid modeling design tool that takes advantage of the
easy-to-learn Windows graphical user interface. You can create
fully associative 3D solid models, with or without constraints,
while using automatic or user-defined relations to capture the
design intent.
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23. • FLAT PISTON TYPE:
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24. • DOME PISTON TYPE:
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25. • CUP PISTON TYPE:
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26. • BOWL PISTON TYPE:
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27. THERMAL ANALYSYS
• Flat Type piston Geometry :
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28. Expected outcomes
• Material properties for AL4032 :
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29. Meshed model
• Type of element : Hexahedral:
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30. Boundary condition
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31. 31

32. Temperature distribution along path
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33. 33

34. Cup Type piston Geometry
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35. Temperature Results
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36. Temperature distribution along path
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37. 37

38. Dome type piston Geometry
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39. Boundary condition
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40. Temperature results
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41. Temperature distribution along path
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42. Temperature distribution along path
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43. Bowl type piston Geometry
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44. Boundary conditions
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45. Temperature results
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46. Temperature distribution along path
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47. Temperature distribution along path
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48. Structural analysis of flat type piston
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49. Structural analysis of flat type piston
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50. Equivalent stress
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51. Equivalent stress along path
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52. Equivalent stress along path
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53. Cup type piston geometry
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54. Boundary condition for cup type
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55. Equivalent stress
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56. Equivalent stress along path
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57. Thermal expansion(deformation)
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58. Dome type piston geometry
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59. Boundary condition for Dome type piston
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60. Equivalent stress
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61. Equivalent stress along path
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62. Thermal expansion (deflection)
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63. Bowl type piston geometry
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64. Boundary condition for Bowl type piston
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65. Equivalent stress
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66. Equivalent stress along path
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67. Thermal expansion(deflection)
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68. Conclusion
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69. • After Performing Thermal Analysis and structural Analysis, it is found
that while using Aluminum Material among four pistons, flat type and
the Dome piston is obtained with lowest stress valves. So those two
types are considered as best type where their values in both Thermal
stress analysis and deflection in geometrical structural analysis were
optimal than compared to the other two types of the pistons which are
noted.
• From the above table it was clear that the flat type and dome type
pistons values in thermal stresses are 80.11 and 80.24 Mpa respectively,
, which are very efficient than other two types of pistons.
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70. • Likewise in structural analysis the deflection was found to be very
optimal in flat and dome type piston which was noted as 0.02 and
0.01 mm respectively hence it is clear from the above study that
using aluminium alloy AL4032 the flat and dome type pistons are
efficient in both thermal and structural analysis.
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71. References
1. S. Srikanth Reddy, Dr. B. Sudheer Prem Kumar Did Thermal
Analysis and Optimization of I.C.Engine Piston Using Finite
Element Method.
2. G.V.N. Kaushik did “Thermal and Static Structural Analysis on
Piston”.
3. K.S.Mahajan and S.H.Deshmukh did “Structural and Thermal
Analysis of Piston”.
4. A.R. Bhagat, Y. M. Jibhakate & Kedar Chimote did “Thermal
Analysis and Optimization of I.C. Engine Piston Using Finite
Element Method”.
5. Preeti Kumari, Anamika & Dr.H.C.Thakur did “Thermal Analysis
ofPiston of IC engine”.
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72. Thank You
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