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An experimental heat release rate analysis was conducted on a six cylinder, 12.7 liter Detroit Diesel Series 60 turbocharged engine operating under steady state conditions. The overall chemical, or gross, rate of heat release and the net apparent rate of heat release were determined from experimental measurements. The gross, time averaged, heat release rate was determined by two separate concepts/methods using exhaust gas concentration measurements from the Nicolet Rega 7000 Real Time Exhaust Gas Analyzer and the measured exhaust gas flow rate. The net apparent rate of heat release was determined from the in-cylinder pressure measurements for each of the six cylinders, averaged over 80 cycles. These pressure measurements were obtained using a VXI based Tektronix data acquisition system and LabVIEW software. A computer algorithm then computed the net apparent rate of heat release from the averaged in-cylinder pressure measurements.

The methodology for predicting the transient mixing rate is presented for a direct injection, quiescent chamber diesel. The mixing process is modeled as a zero-dimensional, large-scale phenomena which accounts for injection rate, cylinder geometry, and engine operating condition. As a demonstration, two different injection schemes were investigated for engine speeds of 1600, 2100, and 2600 rpm. In the first case, the air-fuel ratio was fixed while the injection rate was allowed to vary, but for the second case, the injection duration was fixed and the air-fuel ratio was allowed to vary. For the former case, the resulting mixing rate was also compared with the experimentally determined fuel burning rate. These two quantities appeared to be correlated in some manner for the various engine speeds under investigation.