柴油/天然气双燃料发动机性能研究

对比研究柴油/天然气双燃料发动机的动力性、经济性和排放特性,为柴油/天然气双燃料发动机性能开发奠定基础。在YN33CRD2高压共轨柴油发动机进气歧管加装天然气燃料喷射系统形成柴油/天然气双燃料发动机,并利用自主开发的双燃料ECU控制器及双燃料控制策略进行柴油/天然气双燃料发动机进行控制。试验结果表明:在动力性方面,柴油/天然气发动机的动力性可维持纯柴油模式的原机水平,且经济性和整体排放性能得到了较大改善,天然气替代率最高可达到85%;在经济性方面,在双燃料模式下,发动机的有效燃油消耗率要低于纯柴油模式约3%~7%,且有效热效率要高于纯柴油模式约1%~3%;在排放特性方面,在双燃料模式下发动机的NOx排放和碳烟排放均低于纯柴油模式,但碳氢排放总量高于纯柴油模式,主要是由于天然气燃烧不彻底的特性导致的。综合来看,柴油/天然气双燃料发动机较纯柴油模式可具有较好的综合性能,具有较好的发展前景。

Research on Performance of Diesel/Natural Gas Dual Fuel Engine

A comparative study of the performance of the power,economy and emission between diesel/natural gas dual fuel engine and pure diesel engine was carried out,which lays solid foundation for development of high performance diesel/natural gas dual fuel engine.Based on a common rail diesel engine(YN33 CRD2),the natural gas fuel injection system was retrofitted at the intake manifold to form a diesel/natural gas dual fuel engine.The electronic control unit(ECU)of the new duel fuel engine was selfdeveloped.The experiment results show:firstly,in the term of the power performance,the diesel/natural gas duel fuel engine can maintain the original level of pure diesel engine,and the economic and overall emission performance is better,and the natural gas replacement rate reaches up to 85%.Secondly,the effective fuel consumption rate of the duel fuel engine is 3%~7%lower than that of the pure diesel,and the effective thermal efficiency is 1%~3%higher than that of the pure diesel.Thirdly,the NOx emissions and soot emissions of the duel fuel engine are lower than the pure diesel mode,but due to the incomplete combustion characteristics of natural gas,the total hydrocarbon emissions are higher than the pure diesel engine.On the whole,the diesel/natural gas dual fuel engine has better comprehensive performance than the pure diesel mode,and it has a better development prospect.