NO<SUB align=right>x reduction in diesel engines using rate shaping and pilot injection

Abstract

Reduction in NOx and soot in light and medium duty diesel engines and meeting the US emission standards is an important challenge. This paper shows how Injection Rate Shaping (IRS) should be performed to reduce NOx while engine performance and soot formation remain almost constant. Effects of intercooler with and without rate shaping on NOx reduction will be investigated. Results indicated that the rate shaping and pilot/split injection was an effective technique to reduce NOx at some operating condition. Combined effects of intercooler and rate shaping have shown a reduction of NOx by 50% for some operating conditions. At idle condition, a split injection was found to be a good solution for NOx reduction. A combustion simulation computer program was used in this analysis for six different operating conditions. It was found that the cost of modification of the production line is negligible for mass injector production.