A Study on the Accurate Calculation Method of Heat-Release Rate in Swirl Chamber Indirect Injection Diesel Engine

Abstract

Taking the two chambers of swirl chamber indirect injection diesel engine (SC engine) as two relative but independent thermodynamic systems, this paper builds up thermodynamic equations respectively in the two chambers, together with the mass and enthalpy flow equations describing the mass and energy exchanges between them. This model, based on the synchronous pressure diagrams measured in the two chambers, is used to calculate the thermodynamic state of medium and heat-release process in both of the chambers. Furthermore, with the help of the thermodynamic equivalent system, the calculation of the variable flow coefficient of the connecting passage has been successfully achieved. A Model 6105Q SC engine is taken as a practical calculation example to reveal the combustion pattern of this type of engine. In the last part of this paper, several methods currently used for the heat-release rate calculation have been analysed to show their application field and accuracy.