A Study on Combustion in Direct-Injection Diesel Engine (3rd Report) : (Crosssectional Observation of a Shallow-Dish Chamber)

抄録

As a sequel to the high-speed photographic studies on combustion in direct-injection diesel engines, the progress of combustion in a quiescent shallow-dish chamber with a multi-hole nozzle centrally located has been investigated by taking a crosssectional view of the combustion chamber. This has been attained with a two-cycle engine with specially designed cylinder-head and piston, which simulates only a sector of the injector and piston-cavity arrangement. As the result of observation, it has been revealed that a considerable amount of the fuel is conveyed to the cylinder head after the spray hits the wall of piston cavity, governing the flame development in the middle and later stages of burning, and that the fuel which penetrates into the clearance space makes a substantial source of soot cloud. Further, the influences of the direction of the fuel spray, the opening pressure, and the profile of the chamber on the progress of burning have been evaluated.