可调二级增压柴油机瞬态加载性能的试验

对柴油机用可调二级增压系统进行了瞬态加载试验研究,建立了可调二级增压系统的柴油机瞬态试验系统,通过全工况范围内的稳态试验进行了可调二级增压旁通阀调节规律分析研究.基于稳态的旁通阀调节规律确定了瞬态加载过程的试验方法,进行了3条转速线上的瞬态定转速加载性能试验.试验结果表明:较低转速高负荷时应关闭涡轮旁通阀来改善燃烧,相应瞬态过程中在低负荷时也应关闭旁通阀来避免增压压力上升缓慢和排放性能差等问题.针对较高转速提出了一种修正调节规律,从而有效地提高了增压系统对柴油机加载过程的响应特性,同时也改善了烟度排放.

Experimental on Load Transit Performance of Diesel Engine with Regulated Two Stage Turbocharging System

Experimental study during load transit was conducted on a regulated two stage turbocharging(R2S) diesel engine.Transient test system of diesel engine with R2S was built.Regulating maps of R2S bypass valves were analyzed through the comprehensive steady-state experiment.Experimental method of load transit process was determined based on the steady-state regulating maps of bypass valves.Load transit performance test at same speed was conducted under three speed lines.Experimental results showed that the turbine bypass valve should be closed at low speed and high load.At low load,bypass valve was also closed to avoid the slowly rising of boost pressure and poor emissions performance.One modified regulating map was proposed to improve the response of turbocharging system of diesel engine.Meanwhile,smoke emission was improved.