小喷油量情况下喷油孔截面积对喷油器喷射性能的影响

Influence of Nozzle Flow Area on the Injection Performance under Small Injection Quantity

本文对一款商用系列电磁阀喷油器进行了建模仿真,通过与实验数据中的喷油速率和喷油量map图的对比验证了模型的可靠性,论文主要研究了小喷油量情况下喷油孔截面积对于喷油器单次和多次喷射性能的影响。研究结果表明:喷油器在较小的激励脉宽下随着喷油孔总流通截面积的减小,喷油量先增大后减小,而针阀升程却单调上升。同时,当喷油孔截面积较小时,喷油量的相对循环波动也较小。因此,为了满足柴油引燃天然气发动机对柴油喷嘴最小喷油量的需求,同时保证针阀能够稳定的开启(针阀升程较大)、保证喷射的稳定性,需要适当地选择喷油器尺寸。

In this work the 1D model of a commercial series solenoid injector for a Light-Duty Common Rail system was implemented and validated by using experimental data, such as injection rate and total injected volume. Then the model was applied to study the influences of nozzle flow area on the single-and multi-injection performance under small injection quantity. The results show that the total injected mass increases first and then decreases, when the nozzle flow area is reduced at a short energizing time, but the needle lift increases monotonically. Meanwhile, the cyclical fluctuation of injection quantity under multi-injection strategy is low, when the nozzle flow area is small. In order to satisfy the demands of minimum injected diesel quantity on natural gas engines, at the same time to insure stable opening of needle（higher needle lift） and to guarantee the injection stability, the size of nozzle holes should be carefully selected.