It is well known that heat transfer phenomena are complex in the diesel engine piston. So, it is assumed that the major
mechanism of heat transfer between the combustion chamber and the piston surface is the convection in the thermal
stress analyses. A convection heat load is applied to the piston crown surface. That is, the convection heat load is
enhanced to take into account the radiation effect. The engine in wide open throttle (WOT) condition is considered.