Optimization of Injection Law for a D.I. Diesel Engine

This paper describes how different timing and shape of the injection law can influence pollutant emission of a direct injection diesel engine. The study was carried out making use of a "multizone" thermodynamic model as regards the closed valve phase, and a "filling-emptying" one as regards the open value phase. After being calibrated by comparison with experimental data, the abovementioned model was used for injection law optimization as regards minimum pollutant concentration (NO(x) and soot) in the exhaust gases with the smallest engine performance reduction possible.