为了对乙醇,柴油混合燃料的应用和研究获取更全面的认识,在增压柴油机上对比了燃用纯柴油时与泵掺法(高压油泵掺醇)、化醇法和蒸气法(进气道掺醇)对排放性能的影响.研究结果表明,泵掺法的当量燃油消耗率优于原机;化醇法和蒸气法在低、中负荷范围内的当量燃油消耗率增大,在中、大负荷范围内接近原机水平.泵掺法的HC排放较原机有一定的增加;CO排放在小负荷工况略有上升,大负荷时明显低于原机;NOx排放有所下降,排气烟度显著降低.化醇法和蒸气法与原机比较,在所有工况的HC、CO排放均大幅上升;NOx排放降低的幅度不大,排气烟度有一定的降低.高压油泵掺醇方式对增压柴油机性能的改善效果明显优于进气道掺醇方式.
For a more comprehensive understanding of ethanol/diesel blends application, the comparison experiments of emission were carried out on a turbo-charged to study the effects on performance of diesel engine of supplying pure diesel oil and diesel/ ethanol blends mixed by high pressure pump, carburetor and evaporator(ethanol mixed through intake pipe). The results show that the equivalent oil consumption rate by using pump is better than that of the original engine,and that the equivalent oil consumption rate by using carburetor and evaporator rises at low and medium loads , and is close to that of the original engine at the full load condition. By using pump , the emission of HC has a little increase compared with that of the original engine; CO diseharges slightly rise at low load conditions, and are obviously lower than that of the original machine at high load conditions; NOx is decreased to a certain agree and exhaust smoke is reduced notably. By using carburetor and evaporator , HC and CO rise sharply compared with the use of the original machine at all operating conditions; NOx emission is only decreased slightly, and exhaust smoke is reduced to the extent. Therefore, supplying ethanol through high-pressure oil pump is obviously superior to that through intake pipe in improving the discharge performance of diesel engine.