柴油/丙烷混合燃料发动机燃烧和排放特性研究

比较了柴油和丙烷的主要理化性能;在一台单缸直喷式柴油机上开展了燃用柴油和柴油/丙烷混合燃料时的发动机燃烧和排放特性研究.研究结果表明：在相同工况下,与燃用柴油相比,燃用柴油/丙烷混合燃料时的有效热效率增加,柴油/丙烷混合燃料的有效热效率随丙烷比例的增加而稍有增加,混合燃料的滞燃期和燃烧持续期随丙烷比例的增加而缩短;缸内最大压力,最大燃烧放热率,最高平均燃烧温度随丙烷比例的增加而增加.燃用丙烷柴油混合燃料可同时降低CO、HC和碳烟排放,但NOx排放有所增加.

Study on Combustion and Emission Characteristics of a Diesel Engine Fuelled with Diesel-Propane Blends

In this paper, the physical and chemical properties of diesel and propane were compared. Engine combustion and emission characteristics fuelled with diesel fuel and propane-diesel blends in a singlecylinder, direct-injection engine were investigated. The results showed that under the same operating condition, the engine effective thermal efficiency of diesel-propane blends gave a Slightly higher value comparing to that of pure diesel, and the effective thermal efficiency increased with the increase of propane proportion in the blends. Ignition delay and combustion durations of diesel-propane blends were shortened, and they decreased with the increase of the propane proportion in the blends. The maximum cylinder pressure, the maximum rate of heat release and the maximum mean combustion temperature of diesel-propane blends increased with the increase of propane proportion in the blends. Simultaneous reduction in exhaust CO, HC and smoke emissions could be realized when operating on the diesel-propane blends, however, exhaust NOx emission gave an increasing trend.