Improvement of Diesel Combustion by In-cylinder Air Injection

Abstract

For improvement of diesel combustion efficiency, in-cylinder air injection was attempted. Air injector was installed near fuel injection nozzle on a single cylinder diesel engine. The effects of air injection duration and timing on the diesel combustion performance were investigated. Compared with the conventional diesel combustion, air injection case showed higher peak of heat release rate, improvement of indicated work and reduction of the smoke emission. These results suggest that air injection near the fuel injection nozzle can improve the combustion performance by promoting air entrainment into the diesel spray flame.