Analysis of Heat Release Dynamics in a Compression-Ignition Engine with Multiple Fuel Injection

Zdzisław Chłopek , Jakub Lasocki

Abstract

The heat release characteristics of the combustion process in a four-stroke compression-ignition engines depend strongly on the fuel injection strategy. In the case of multiple fuel injection, deviations from the classic heat release model applicable to a single injection are observed. This paper presents the results of empirical tests and their analysis for a single-cylinder compression-ignition research engine with double injection of fuel. The influence of fuel injection pattern on the indicated pressure has been analyzed, in particular the derivative of indicated pressure in respect of the crank angle. The processes of fuel supply and heat release have been investigated in time domain. A correlation analysis of voltage controlling the opening of injector and unit heat release rate have been presented. The delay angle and delay time of unit heat-release rate in respect of the voltage controlling the opening of the injector have been determined. The heat release for each injected fuel dose has been analyzed.