Abstract
The in-cylinder combustion process of a grou-hole nozzle was investigated by using a single-cylinder optical research engine. From the direct images of the flame, distribustions of the flame luminosity were analyzed. Two-color method was also employed to obtain flame temperature and KL factor. Effects of the group-hole nozzle on the combustion process were clarified by comparing with 6-hole nozzle and 12-hole Nozzle. In the case of the group-hole nozzle, the low soot formation during the combustion process and the low fuel consumption were achieved compared with the conventional 6-hole nozzle.
