Experimental study on flat

Reducing heat loss is one of the most important development concerns for improving the thermal efficiency of the diesel engine. In order to know heat transfer through the combustion chamber wall more clearly, the effects of flame impingement on transient heat flux to the wall were investigated. Using a high-pressure and high-temperature chamber under diesel engine–like conditions, fuel was injected from a single-hole injector against an impingement wall. Surface heat flux of the impingement wall was measured by temperature with three thin film thermocouple heat flux sensors. Simultaneously, luminous flame, flame temperature, and soot distribution were also investigated. The results showed that temperature near the wall and flame contact area have great influence on the local heat flux. Furthermore, local heat flux, combustion, and soot formation reached maximum levels at some spray impingement distance to the wall