Effect of Nozzle Structure Parameters on Steady Emission Characteristics in an Opposed-Piston Two-Stroke Diesel Engine

Abstract

According to 8-Mode cycle of measurement methods for non-road diesel engine of China III from GB20891-2014, the effects of the injection parameters on steady emission characteristics were researched on an opposed-piston two-stroke(OP2S) diesel engine. Test results show that nozzle-tip-protrusion(NTP) can’t make a big influence on emission characteristics, but all of the CO, NOx and PM emissions decrease obviously with the increase of injector hole diameter. Moreover, there exists an optimal nozzle hole cone angle, which can lead to a least composite rate emission. Compared with the original engine, the gross emissions of NOx and HC decrease approximately by 17.2% for improved OP2S engine after nozzle parameters optimization matching, and the improved OP2S engine is able to meet non-road diesel engine of China III emission requirement.