modeling andthermal analysis of piston

MODELING ANDTHERMAL ANALYSIS OF PISTON

1M CHALAPATHI 2S.PRAVEEN KUMAR

1Department of Mechanical Engineering M-Tech Student (CAD/CAM) Chadalawada Ramanamma Eng.

College.

2Department of Mechanical Engineering Assistant Professor (CAD/CAM) Chadalawada Ramanamma Eng.

College.

ABSTRACT: In this investigation, Work is done to

discover the Thermal stress distribution on various

Piston Materials utilized. In IC engine Piston is a the

most important element in engine element and

complex part, so it is essential to keep up Piston in

good condition in order to attain good condition of

the engine. Piston main fails due to mechanical and

thermal stress.

So as to search out proper mechanical stress

as well thermal distribution on Piston Materials are

considered. In this analysis is work out on piston with

different materials (AL-Si Alloys, AL-Mg-Si Alloys,

and AlSiC alloy). The piston is modeled and analyze

by using Computer aided design and Computer aided

engineering software. In this analysis I found that the

vonmisses stress, heat flux reduces in AlSiC

composite compared with otheraluminum alloys.

INTRODUCTION: A piston is a element

of reciprocating engines, reciprocating pumps, gas

compressors and pneumatic cylinders, etc. It is the

reciprocating component that is contained by

a cylinder and is made gas-tight by piston rings.

In an engine, the piston purpose is to transfer motion

from expanding gas in the cylinder to

the crankshaft via a piston rod and/or connecting rod.

In a pump, the function is modified and motion is

transferred from the crankshaft to the piston for the

purpose of compressing or ejecting the fluid in the

container. In some engines, the piston also acts as

a valve by covering and uncovering ports in the

cylinder wall.

Internal combustion engines:

Figure 1 : Internal combustion engine piston,

sectioned to show the gudgeon pin.

The connecting rod is associated with the cylinder by

a swiveling gudgeon stick (US: wrist stick). This

stick is mounted inside the motor cylinder: not in any

way like the steam motor, there is no cylinder or

cross head (beside enormous two stroke motor).

Trunk pistons:

Trunk pistons are long relative to their diameter.

They act both as a cylindrical crosshead and piston.

As the connecting rod is angled for much of its

rotation, there is also a side force that reacts along the

side of the piston against the cylinder wall.

Crosshead pistons

Huge moderate speed Diesel motors may require

extra help for the side powers on the cylinder. These

motors ordinarily utilize cross head cylinders. The

fundamental cylinder has a substantial cylinder pole

stretching out downwards from the cylinder to what

is adequately a moment littler distance across

cylinder. Slipper pistons:

A cylinder for an oil motor that has been decreased in

size and weight however much as could be expected.

In the extraordinary case, they are diminished to the

cylinder crown, bolster for the cylinder rings, and

sufficiently only of the cylinder skirt staying to leave

two terrains in order to stop the cylinder shaking in

the drag.

Deflector pistons:

International Journal of Research

Volume 7, Issue XII, December/2018

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Page No:1571

Two-stroke deflector piston

INTRODUCTION TO FEM

1.1 NEED FOR FEM

Numerous building issues dealt with today don't have

shut type of Solution. For these issues, geometry of

the protest is sporadic or some of the time self-

assertive. Prior to disregard the challenges in taking

care of these genuine issues, rearranging suppositions

were made. Numerical techniques, which give rough

arrangement, appeared. These strategies can hold the

issue complexities, giving a superior arrangement.

GENERAL DESCRIPTION OF THE METHOD

In transitory the it all about of FEM is the cross

section of a biggest slice of the cake or practice by an

set of subdivisions called finite elements. These

graphic representation are thought-about inhume

wired at joints, that are experienced as nodes or nodal

points. Simple functions are selected to mirror the

selection or mutation of the distinct displacements

completely each finite element. Such on a long shot

functions are met with as driving out functions or

driving out models. The long shot magnitudes of the

ejection functions are the displacements at nodal

points.

BASIC CONCEPT OF FEM

“The most gracefulness of the FEM that separates it

from others is that the division of a given domain into

a collection of straightforward sub domains known as

finite elements. Any geometric form, that permits

computation of the solution or its approximation or

provides necessary relations among the values of the

solution at selected points, known as nodes of the sub

domain, qualifies as a finite element.

REDUCING THE DESIGN AND

MANUFACTURING COSTS USING ANSYS

(FEA):

The ANSYS program enables specialists to build PC

models or exchange CAD models of structures,

items, segments, or frameworks, apply loads or other

outline execution conditions and concentrate physical

reactions, for example, feelings of anxiety,

temperature conveyance or the effect of lector

attractive fields.

Rock Mechanics:

Tunnels, mines, pit, cavities, and bore holes.

Geological features like Joints, fissures fractures and

layers.

Hydro Elasticity:

Sloshing of liquids in flexible containers,

reservoir or darn interactions.

AlSi Material properties

Sl No properties Value

1 Young’s modulus 2.3×105 Mpa

2 Poisons ratio 0.24

3 Density 2937 kg/m3

4 Thermal conductivity 197 W/m0C

5 Specific heat 894 J/kg0C

Compositions of AlSi alloy

1 Cu 1.1%

2 Zn -

3 Mn 0.2%

4 Fe 0.3%

5 Mg 1.1%

6 Si 12.5%

7 Ti -

8 Sn -

9 Pb -

10 Ni 0.9%

11 Al Rest

Al-Mg-Si Material properties


1 Young’s modulus 0.7 ×105 Mpa





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Compositions of Al-Mg-si

1 Aluminium: 97.9 to 99.3%

2 Chromium: 0.05% max

3 Copper: 0.1% max

4 Iron: 0.1 to 0.3%

5 Magnesium: 0.35 to 0.6%

6 Manganese: 0.10%

7 Silicon: 0.3 to 0.6%

AlSiC-10 Material properties







Compositions of AlSiC-10

Aluminum Alloy A 356.2 45 vol%

Silicon Carbide 55 vol%

Compositions Aluminum Alloy A 356.2

Aluminum, Al 91.2 - 93.1 %

Copper, Cu <= 0.10 %

Iron, Fe 0.13 - 0.25 %

Magnesium, Mg 0.30 - 0.45 %

Manganese, Mn <= 0.05 %

Other, each <= 0.05 %

Other, total <= 0.15 %

Silicon, Si 6.5 - 7.5 %

Titanium, Ti <= 0.20 %

Zinc, Zn <= 0.05 %

AlSiC-12 Material properties







Compositions of AlSiC-12

Aluminum Alloy A

356.2

63 vol%

Silicon Carbide 37 vol%

Compositions Aluminum Alloy A 356.2

Aluminum, Al 91.2 - 93.1 %

Copper, Cu <= 0.10 %

Iron, Fe 0.13 - 0.25 %

Magnesium, Mg 0.30 - 0.45 %

Manganese, Mn <= 0.05 %

Other, each <= 0.05 %

Other, total <= 0.15 %

Silicon, Si 6.5 - 7.5 %

Titanium, Ti <= 0.20 %

Zinc, Zn <= 0.05 %

MODELING

2.1. Piston Design

The piston is designed according to the procedure

and specification which are given in machine design

and data hand books. The dimensions are calculated

in terms of SI Units. length, diameter of piston and

hole, thicknesses, etc., parameters are taken into

consideration

2.1.1. Design Considerations for a Piston

In designing a piston for an engine, the

following points should be taken into

consideration:

It should have enormous strength to

withstand the high pressure.

It should have minimum weight to withstand

the inertia forces.

It should form effective oil sealing in the

cylinder.

It should provide sufficient bearing area to

prevent undue wear.

It should have high speed reciprocation

without noise.

It should be of sufficient rigid construction

to withstand thermal and mechanical

distortions.

It should have sufficient support for the

piston pin.

2.1.2 Piston Design specification



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a) Consider Diameter of Bore

b) Width of the top land(b)

c) Height of the piston(H)

d) Distance from the front to the axis of piston

pin(h1)

e) Diameter of thickness of piston pin(d)

f) Distance from the front to the first channel(e)

g) Wall thickness between channels(hn)

h) Radial thickness of the piston ring (tr)

i) Axial thickness of the piston ring (ta)

Fig Piston Geometry

Table 1 Selected Dimensions of Design Specification

of the piston

Ansys 3D Model

Thus, the dimensions for the piston are calculated and

these are used for modelling the piston in Ansys work

bench Modeller. Thus, a symmetric model is

developed using the above dimensions. Piston was

modelled using Ansys software which is shown in

Figure 1.

the complete three-dimensional model of

piston geometry was created using Ansys work bench

Modeller. The part and is shown in figure 5.1.

MESHING OF PISTON

The piston shape is irregular, especially in

the presence of various curved surfaces of inner

cavity. Firstly, Automatic meshing method is used to

mesh the model.Element used is 20 node Tetrahedron

named soilid90 . The element size is taken as 5, then

total number elements were 11475 and nodes were

19591 found in meshed model.

The mesh grid is shown as figure below .

THEORETICAL CALCULATIONS

Structural

Sl .No Material Total Deflection (mm)

1 AlSi 0.04197

2 Al-Mg-Si 0.1304

3 AlSiC-10 0.057

4 AlSiC-12 0.05869

AlSi

Fig(1); Vonmises stress of AlSi piston



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Fig(2); Total deformation of AlSi piston

Fig (1) and Fig (2) show the structural

results of aluminium silicon Alloy piston influenced

by gas pressure.

Fig (1) show the distribution of Vonmises

stresses induced within the piston body. The

maximum values of equivalent stresses observed at

centre portion of the piston crown is 89.929 Mpa.

Fig (2) show the maximum deflection in the

piston geometry due to the application of gas

pressure is 0.042167 mm, which is observed at the

central portion of the piston crown.

Al-Mg-Si

Fig(1); Vonmises stress of Al-Mg-Si piston

Fig(2); Total deformation of Al-Mg-Si piston


results of Al-Mg-Si Alloy piston influenced by gas

pressure.









AlSic-10

Fig(1); Vonmises stress of AlSiC -10piston

Fig(2); Total deformation of AlSiC-10 piston


results of AlSiC-10 Alloy piston influenced by gas

pressure.









AlSiC-12

Fig(1); Vonmises stress of AlSiC -12piston



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Fig(2); Total deformation of AlSiC-12 piston


results of AlSiC-12 Alloy piston influenced by gas

pressure.









S

NO

MATERIAL

VONMISSES

STRESS (

MPa)

TOATAL

DIFLECTION

(mm)

1 AlSi 89.929 0.042167

2 Al-MgSi 96.739 0.13527

3 AlSiC-10 90.749 0.057958

4 AlSic-12 87.771 0.058328

S

NO

MATERIAL TOATAL DEFLECTION

Ansys Theoretical

1 AlSi 0.042167 0.04197

2 Al-MgSi 0.13527 0.1304

3 AlSiC-10 0.057958 0.057

4 AlSic-12 0.058328 0.05869

Maximum Heat flux of the piston crown

q= -k ……………………..From Fourier’s law

K= Thermal conductivity of piston

material

dT=Temperature gradient (T2-T1)

dx=Thickness of the top land of the

piston (t)

q= -k

T2= Temperature of the top surface of the piston

crown.

T1=Temperature of the Bottom surface of the piston

crown.

t = Thickness of the top land of the piston

CaseI Maximum Heat flux in AlSi Alloy Piston

q= -k

q = -197 ×

=3.788 x 106 W/m2

Case-II Maximum Heat flux in Al-Mg-Si Alloy

Piston

q= -k

q = -200 ×

=3.846 x 106 W/m2



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Case-II Maximum Heat flux in AlSiC-10 Alloy

Piston

q= -k

q = -190 ×

=3.653 x 106 W/m2

Case-II Maximum Heat flux in AlSiC-12 Alloy

Piston

q= -k

q = -170 ×

=3.269 x 106 W/m2

AlSi

Fig(1); Temperature distribution for AlSi piston

Fig(2); Total heat flux for AlSi piston

Fig (1) and Fig (2) show the Thermal results

of aluminium silicon Alloy piston influenced by gas

Temperature.

Fig (1) show the distribution of Temperature

induced within the piston body. The maximum values

of Temperature observed at top surface of the piston

crown .

Fig (2) show the maximum total heat flux in

the piston geometry due to the application of gas

temperature is 3.0227 MW/m2, which is observed at

the edge portion of the piston crown.

Al-Mg-Si

Fig(1); Temperature distribution for Al-Mg-Si

piston

Fig(2); Total heat flux for Al-Mg-Si piston

Fig (1) and Fig (2) show the Thermal results

of aluminium silicon Alloy piston influenced by gas

Temperature.

Fig (1) show the distribution of Temperature

induced within the piston body. The maximum values

of Temperature observed at top surface of the piston

crown . Fig (2) show the maximum total heat flux in

the piston geometry due to the application of gas

temperature is 3.0375 MW/m2, which is observed at

the edge portion of the piston crown.

S No Material Total Heat flu (MW/m2)

1 AlSi 3.0227

2 Al-Mg-Si 3.0375

3 AlSiC-10 3.0212

4 AlSiC-12 2.774



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Sl No Material Total heat Flux (MW/m2)

Theoretical Simulated

1 AlSi 3.788 3.0227

2 Al-MgSi 3.846 3.0375

3 AlSiC-10 3.653 3.0212

4 AlSic-12 3.269 2.774

The maximum heat flux was observed is 9.1716

MW/m² . Maximum vonmisses stress was observed

at top land of the piston is 89 Mpa and the maximum

deflection of the piston due to gas pressure is 0.434

mm

Conclusion:

1. From the analysis results of different

material on piston is observed that

deformation, Vonmises stress, total heat flux

reduces in AlSiC composite compared to Al-

Si, Al-Mg-Si, Alloy.

2. Theoretical calculation of the piston have

been done to get the influence of thermal

load and mechanical load.

3. The maximum Vonmises stress for heat flux

total deforming reduced by increases

composition of carbides in AlSiC Alloy.

4. Results comparison between theoretical and

analysis simulated done and found

approximately same.

5. Results comparison was done with previous

other papers which were taken as references.

And almost approximate results were

observed.

Scope of feature works

• The work can be entered by using some

more types of Aluminium alloys.

• Different shapes of piston crown may be

analysed.

• Aluminium alloys may be coated with

aluminium oxides for piston working at

elevated temperature.

REFERANCES

• ”Thermal Analysis and Optimization of

I.C. Engine Piston Using Finite Element

Method”International Journal of Innovative

Research in Science,Engineering and

Technology. S.SrikanthReddy,

Dr.B.SudheerPremKumar,Vol.2, Issue12,

December 2013.

• “Piston Design and Analysis by CAE

Tools” Ghodake A. P.*, Patil K.N. IOSR

Journal of Engineering (IOSRJEN) ISSN:

2250-3021 ISBN: 2878-8719 PP 33-36

• “Experimental Investigation and Analysis

of Piston by using Composite Materials”

R. RAVI RAJA MALARVANNAN1, P.

VIGNESH.International Journal of

Mechanical Engineering applications

Research.Vol 04, Article-K100;

• “Piston Strength Analysis Using FEM” by

Swati S Chougule*, Vinayak H

Khatawate**International Journal of

Engineering Research and Applications

(IJERA) ISSN: 2248-9622.

• “ Design, Analysis and Optimization of

Three Aluminium Piston Alloys Using FEA” by Ajay Raj Singh*, Dr. Pushpendra

Kumar Sharma. Journal of Engineering

Research and Applications ,ISSN : 2248-

9622, Vol. 4, Issue 1( Version 3, January

2014, pp.94-102.

• “Thermal Analysis And Optimization Of

I.C. Engine Piston Using finite Element

Method” by A. R. Bhagat1, Y. M. Jibhakate

2. International Journal of Modern

Engineering Research (IJMER), Vol.2,

Issue.4, July-Aug 2012 pp-2919-2921.



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modeling andthermal analysis of piston

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