Analytical investigations on heat transfer in a low heat rejection DI diesel engine

Diesel engines are increasingly becoming important because of their fuel economy and efficiency. Now-a-days, ceramic coating over the cylinder head, valves and the piston top surfaces are provided for thermal insulation. These thermal barrier coatings reduce the heat transfer from the combustion chamber to the cooling jackets and to the atmosphere. This paper presents the investigation of the temperature distribution over the cylinder head, valves and the piston resulting from coating those using Partially Stabilized Zirconia (PSZ) thermal barrier coatings. This analysis is based on the fact that coating thickness affects the heat transfer and temperature distribution in the cylinder head and piston. A 3-D Finite Element Analysis (FEA) using ANSYS is performed to evaluate the temperature distributions over the cylinder head, inlet valve, exhaust valve and the piston. Based on the analysis, it can be concluded that a coating of PSZ over the combustion chamber increases the temperature over the inside the combustion chamber and reduces the heat rejection to the atmosphere.