New Combustion System of the IDI Diesel Engine

Increasing the degree of constant volume of heat release, combustion efficiency and reducing the heat losses are of utmost importance to improving the fuel economy of the indirect injection (IDI) diesel engine. The authors closely analyzed the flow characteristics of the jet passage and the jet in the main chamber, and successfully devised a new combustion system which features a refined jet passage. The new combustion system offers the optimum discharge coefficient of the jet passage and improved diffusion and penetration of jet in the main chamber. Installed in a Mitsubishi S4E2 diesel engine (swirl-chamber system and four cylinders of 98 mm bore and 98 mm stroke each) and tested, the new combustion system was proven to reduce the engine fuel consumption, smoke emission, and noise.