Direct Heat Loss to Combustion Chamber Walls in a Common Rail Type D.I. Diesel Engine

-Influences of Fuel Injection Pressure, Intake Gas Pressure and Oxygen Concentration of Intake gas to Instantaneous Heat Flux-

Abstract

Diesel engines, nowadays, are operating under complex control. There are a great number of parameters for combustion control, such as fuel injection timing, frequency of fuel injection, intake gas pressure, rate of exhaust gas recirculation and swirl ratio. However, no systematic examination of influences of these parameters on direct heat loss has been made. In this study, using thin-film thermocouples (TFTs) , the authors investigated influences of fuel injection pressure, intake gas pressure and oxygen concentration in the intake gas on instantaneous heat flux from combustion gas to combustion chamber walls in a common rail type direct injection diesel engine.