Influence of Uneven Distribution of Combustion Gas in the Cylinder on the Combustion of a Diesel Engine : 3rd Report, Correlation between Speed of Combustion and Concentration Distribution of Combustion Gas

Abstract

Uneven distribution of combustion gas in the cylinder occurs in some open chamber type diesel engines. This phenomenon is generated by an interference of fuel spray on the combustion chamber wall. So the concentration distribution of combustion gas can be used as a measure of interference. In this report, the mean relative burning rate is examined for possibility to express the combustion performance of fuel spray quantitatively. Then, the influence of spray impingement on the combustion performance is examined about the correlation between the concentration distribution of combustion gas and the mean relative burning rate. As a result, the following are revealed. An increase in the mean velocity of fuel spray causes the speed of mixture formation and combustion to increase through whole period, and the impingement of fuel spray suppresses the mixture formation in the injection period and promotes the combustion in the period after the end of injection.