Abstract
Spray evaporation process in a direct injection diesel engine is greatly affected by the in-cylinder temperature but also it is affected by heat transfer process from the combustion cavity wall to the impingement spray. There are lots of literatures concerning with the fundamental studies of evaporation process of diesel spray. However, there are a few investigations about the effect of wall temperature on evaporation process. In this report, the fuel vapor distribution of a diesel spray impinging on a hot wall was measured using the laser induced fluorescence method. To control the wall and the ambient temperatures independently, the surroundings around the nozzle and the wall were heated separately using electric heaters. The result indicated that the hot surroundings entrained into the impingement spray had greater effect than that of the hot wall, even if the wall temperature was higher than the boiling temperature of the fuel.
