Heat Insulation by Temperature Swing in Combustion Chamber Walls (Sixth Report)

- Effect of Improved Surface Roughness of Insulation Coating on Thermal Efficiency and Emission-

Abstract

In the former report (3rd report), authors applied temperature swing insulation pistons except piston cavity, which is to avoid deterioration of the specific fuel consumption due to the surface roughness. In this report, the performance of heat insulation by temperature swing was investigated with the different surface roughness pistons. As the result, the better surface finishing showed the lower specific fuel consumption. Furthermore, utilizing the increased in-cylinder gas temperature of pilot combustion with insulation, fuel injection strategy was re-calibrated, and showed further specific fuel consumption improvement.