Technical Paper
Reduction of NOx in a Single Cylinder Diesel Engine Emissions Using Selective Non-Catalytic Reduction (SNCR) with In-Cylinder Injection of Aqueous Urea
2019-09-09
2019-24-0144
The subject of this study is the effect of in-cylinder selective non-catalytic reduction (SNCR) of NOx emissions in diesel exhaust gas by means of direct injection of aqueous urea ((NH2)2CO) into the combustion chamber. A single cylinder diesel test engine was modified to accept an electronically controlled secondary common rail injection system to deliver the aqueous urea directly into the cylinder during engine operation. Direct in-cylinder injection was chosen to ensure precise delivery of the aqueous urea without the risk of any premature reactions taking place. The injection strategy was four molar ratios, 4.0, 2.0, 1.0 and 0.5 with five varying injection timings of 60, 20, 10, 0, and -30 degrees after top dead center (ATDC). The main secondary injection fluid, aqueous urea, was mixed with glycerol (C3H8O3) in an 80-20 ratio, by mass, with the desire to function as a lubricant for the secondary injector.
