3D mechanical and thermal analysis of an Aluminium piston for a high-speed Diesel laboratory engine

A cast aluminium piston of a single cylinder Petter Diesel engine is modelled using the finite element method. The engine is intended to be supercharged, which will increase the thermal loading on the piston, and so the purpose of this work is to investigate the piston behaviour and strength when subjected to the current level of thermomechanical load. The dimensions of the piston and piston pin is measured, and the materials and boundary conditions are measured, calculated or assumed. Areas of particular interest were the combustion bowl rim and the piston pin boss. The latter was modelled using a contact interaction between the pin and boss, in order to accurately represent its behaviour. The final model is used to investigate the behaviour of the piston, locate the most critically stressed areas and the cyclical stress variations which may lead to fatigue. Local fatigue strength of the material is compared with local stress variations, and it is found that the piston is not exceeding its fatigue strength at any point and its expected lifetime should be quite high for the current loading of the engine