Abstract:
Internal combustion engine piston is subjected to high temperature and pressure due to direct contact
with the combustion process inside the cylinder; therefore for smooth running of vehicle piston should
be in proper working condition. Pistons fail mainly due to mechanical stresses and thermal stresses. In
this thesis work a piston is analyzed by using finite element analysis software named ANSYS
Workbench thermal-stress capability for three different aluminum alloy piston materials (Al6061,
Al4032 and Al-GHS 1300) were conducted and two piston head shape (bowl and flat),the 3D model of
the piston is modeled by using ANSYS 18.2 geometric module.
The parameters used for the simulation are operating gas pressure on piston head, uneven temperature
distribution from piston head to skirt and material properties of piston. The specifications used for the
study of these aluminum alloy pistons is four stroke single cylinder petrol internal combustion engine
of 99.27 cc
The maximum stress occurred at piston pin area, maximum total deformation at the top of piston head,
maximum total heat flux at piston ring areas and minimum factor of safety occur at piston pin area for
all piston materials are considered in the conducted study. The best piston head shape, flat piston head
is selected based on static structural and steady state analysis. Best Aluminum alloy material Al GHS1300 is selected and optimized based thermo-mechanical analysis results.
After conducting the thermo-mechanical analysis and modeling the result including Piston optimized
using response surface optimization module, the thickness of piston barrel is reduced by 19.65% ,the
thickness of piton crown head reduced by 11.58% ,the width of top land reduced by 19.73% ,piston
skirt length reduced by3.51%, axial thickness of the ring increased by4.2% and radial thickness of the
ring increased by 1.1%,mass of piston reduced by13.06% ,maximum von misses stress reduced by
17.34,maximum deformation reduced by 4.3% and factor of safety increased by 17.38%
Further research is required to select a material with less weight and high strength to reduce the inertia
forces
Key words: ANSYS, aluminum alloys, Internal combustion engine, optimization, Piston, Stress
concentration, Thermal, structural and analysis.
