副室式デイーゼル機関の低騒音燃焼研究

第1報,目標燃焼サイクルと低騒音燃焼法

抄録

In order to reduce noise from an indirect injection (IDI) diesel engine, the combustion, cycle characteristics and a low-noise combustion system were investigated. It was found that realizing a heat release mode in the prechamber which consists of a triangle with a reduced heat release rate are of utmost importance for reducing the combustion-induced noise. Also, it was clarified that a high compression ratio in order to shorten the ignition delay, the control of fuel injection direction in order to restrain air entrainment in the fuel spray, and the enlargement of the jet passage area in order to restrain the swirl velocity in the prechamber are effective as methods for reducing noise. The above combustion system was proven to have a reduced heat release rate, pressure rise in the main chamber and noise level.