启喷压力对电控单体泵供油系统喷油量的影响机理

以电控单体泵燃油系统为研究对象,研究了启喷压力对循环喷油量的影响。通过计算各工况下循环喷油量随启喷压力变化的百分比,研究了各工况循环喷油量随启喷压力变化的敏感程度,在此基础上进行了启喷压力对循环喷油量影响的机理分析。结果表明:循环喷油量随启喷压力的增加呈减小趋势,随着转速的增加,启喷压力对循环喷油量的影响程度越来越小;在各确定转速下,随着喷油脉宽的增加,循环喷油量对启喷压力变化的敏感程度越来越低;低速时启喷压力主要通过影响喷油器针阀开启关闭的运动过程而影响循环喷油量,中高速时启喷压力主要通过影响有效喷油脉宽而影响循环喷油量。

Influencing Mechanism of Opening Pressure on Fuel Injection Quantity of Electronic Unit Pump Injection System

For the electronic unit pump (EUP) fuel system ,the influence of opening pressure on fuel injection quantity per cy‐cle was researched .The sensitivity of fuel injection quantity to opening pressure was revealed by calculating the changed per‐centage of fuel injection quantity per cycle to opening pressure and the influencing mechanism of opening pressure on fuel injec‐tion quantity per cycle was researched .The results show that the fuel injection quantity decreases with the increase of opening pressure and is less influenced by the opening pressure with the increase of speed .At each certain speed ,the sensitivity of fuel injection quantity per cycle to opening pressure becomes weaker with the increase of injection pulse width .The fuel injection quantity per cycle is influenced by the opening and closing movement of injector needle valve at low speed and is influenced by the change of effective injection pulse width at medium and high speed .