Mechanical and thermal stresses issues related to a size of a four-stroke piston based on a Renault Premium DXi11 430 460 EEV engine

The size of an engine is one of the factors affecting its thermal efficiency. It is known that with an increase of the size of the engine, the cubic capacity and heat generation grows in the third power, whereas thermal losses are proportional only to the second power of the size (due to heat exchange surface). However, the increase in the size of the engine generates some problems related to its mass, rotational speed and heat load, the last of which is a subject of these considerations. In the article, the influence of the piston size on its thermal and mechanical stresses is considered. Similar boundary conditions for both cases were assumed. Simulation of the steady-state heat transfer and mechanical simulation were carried out using the Finite Element Method. In each analysis, both the original version of the piston and its scaled version were considered. The boundary conditions were adopted on the basis of engine catalogue data and available literature. The results of analyses were discussed.