高压共轨喷油器压力波动与针阀响应解耦分析

Analysis of Pressure Fluctuation and Needle Valve Response Decoupling for High Pressure Common Rail Injector

多次喷射过程中,不同喷射之间的相互影响导致循环喷油量的控制难度增大。建立了高压共轨系统的AMESim仿真模型,通过数值仿真和试验测试相结合的方法,揭示了喷油器内部压力波动和针阀开启阶段动作响应的强耦合作用是导致主喷油量随喷射间隔波动的根本原因,当主喷油量基准值为60.0mm3时,其波动量最大可达3.6mm3。建立了共轨系统的无阻尼LC液力系统模型,通过对模型的分析,针对强耦合作用提出了减小喷油器内部油道长径比和盛油槽容积的解耦方法。对解耦方法的仿真试验验证表明,采用解耦方法后压力波动和针阀响应的耦合程度降低53%。

During the process of multi-injection,the mutual influences between different injections led to the difficult control of cycle fuel injection quantity.The AMESim model of high pressure common rail system was established.The fundamental reason of main injection fluctuation with injection interval was proved to be the strong coupling behavior of internal pressure fluctuation and needle valve opening action by combining the numerical simulation and actual test.The largest fluctuation was3.6mm^3 when the reference value of main injection was 60.0mm^3.In addition,the undamped LChydraulic system model was established and analyzed.The decoupling method of decreasing the length-diameter ratio of internal fuel duct and the delivery chamber volume with respect to the strong coupling was proposed.The simulation verification showed that the coupling degree of pressure fluctuation and needle valve response decreased by 53%.