不同条件下电控喷油器燃油温度变化及影响

Fuel Temperature Change and its Effect of Electronic Controlled Injector under Different Conditions

为说明电控喷油器(Electronic Controller Injector,ECI)燃油温度对喷油量的影响,简要分析了电控喷油器内燃油热交换形式,建立了燃油的摩擦生热模型、强迫对流换热模型和节流温度模型,运用液压流体仿真软件AMESim构建电控喷油器燃油热仿真模型,验证了电控喷油器燃油热模型的有效性,进而分析了不同初始温度下电控喷油器的燃油温度变化情况。结果表明:当入口燃油温度为40、60℃时,与喷射压力为90 MPa时相比,喷射压力为140 MPa时对应的针阀腔和控制室的燃油最高温度和稳定温度变化较大;同一喷油压力下,喷油脉宽1. 0、1. 5 ms时针阀腔的燃油温度变化不大,而初始燃油温度高低对控制室燃油温度影响非常显著;以喷孔出口燃油温度计算循环喷油量,其计算值与实测值的误差较小。

In order to explain the effect of the fuel temperature on the fuel injection quantity of the electronic fuel injector,fuel heat exchange forms of Electronic Controlled Injector(ECI)are briefly analyzed,and the friction heating model,forced convection heat transfer model and throttling temperature model are established.The fuel heat simulation model of ECI with hydraulic fluid calculation software AMESim is built,the validity of the model is verified with experimental data,and then the fuel temperature variation of ECI is analyzed at different initial temperatures.The results shows that in the condition of inlet fuel temperature 40℃and 60℃respectively,the maximum fuel temperature and stable temperature in the needle chamber and control chamber vary greatly when the pressure is 140 MPa compared with the pressure of 90 MPa.The fuel temperature of needle chamber has little change when the fuel injection pulse width is 1.0,1.5 ms under the same pressure,however,the initial fuel temperature level has significant impact on the fuel temperature of control chamber.The circulating fuel injection quantity is calculated by the outlet fuel temperature of the orifice,and the error between the calculated value and the measured value is small.