Study of Heat Rejection Mechanism of a Direct-injection Diesel Engine. 1st Report. Characteristics of Local Heat Flux.

Abstract

Experimental investigations are being conducted on a single-cylinder direct-injection diesel engine to examine the transient heat transfer characteristics. Transient temperature data from stationary locations in the piston and cylinder head were used as the basis for determining the transient heat flux rates. Transient surface temperature was measured using the thin film thermocouples. At first, the transient heat flux rates calulated from the analysis method used in this paper were compared with the results from FEM. The results showed good agreement. Using this analysis method, the transient heat flux rates were calulated. The tests were performed at 1200 rpm with constant air flow. The parameters that were varied included the fuel rate and injection timing. Based on these results, the present paper discusses the mechanism of heat rejection in a direct injection diesel engine.