Thermodynamic Analysis of a Swirl Chamber Diesel Engine

The thermodynamic analysis of swirlchamber engines presents a problem that has not yet been satisfactorily resolved. One of the main reasons for this is the high level of accuracy required for measuring the absolute pressures and pressure differences between the cylinder and swirlchamber and the lack of adequate calculation models for heat transfer and the mass transfer between the two chambers.

The paper describes, firstly, how the method of pressure measurement has been improved. Subsequently, the heat-release analysis of Anisits and Zapf was used, however, this revealed errors in the heat transfer and mass flow rate. A new model for these latter quantities is therefore proposed and has been deveoped using motored pressure measurements.

Results are presented which demonstrate how the method may be applied to calculate the heat release rates in both chambers using measurements from the fired engine and with variations in both load and speed.