Influence of Uneven Distribution of Combustion Gas in the Cylinder on the Combustion of a Diesel Engine : 2nd Report, the Controlling Factors for the Formation of Concentration Distribution of Combustion Gas

Abstract

Uneven distribution of combustion gas in the cylinder occurs in some open chamber type diesel engines. It is considered that this phenomenon is generated by an interaction of fuel spray with the combustion chamber wall. This study aims at revealing the influerace of uneven distribution of combustion gas on the combustion performance of the engine. In this report, the correlation of concentration distribution of combustion gas along the cylinder axis measured by the exhaust gas sampling method with the operating characteristics of fuel injection system, is examined under various operating conditions by changing the load, injection timing, and opening pressure of an injector. As the result it is found that mean fuel velocity through nozzle holes in the injection period, amount of fuel supplied in a cycle, and mean piston position in the injection period are the controlling factors for the formation of concentration distribution of gas.