一种新型共轨喷油器仿真研究

Simulation on a New-type Common Rail Injector

针对发动机对"先缓后急"喷油规律的需求,研究了一种双控制腔进油量孔的新型共轨喷油器。基于AMESim平台建立了喷油器模型,并应用EFS测试数据进行了模型校准。结果表明:与常规共轨喷油器相比,新型共轨喷油器针阀关闭速度提高了2倍,控制腔进油量孔流通面积减少了50%以上,更容易得到"先缓后急"的靴形喷油规律;减小控制腔容积可以提高喷油响应速度,增加滑阀弹簧预紧力可以提高滑阀恢复速度,以上措施能够提高新型喷油器的多次喷射能力,满足不同发动机性能需求;受滑阀副油道的作用,新型共轨喷油器在单结构参数、单次喷射条件下,喷油一致性受加工误差影响系数降低。

According to the first slow and then fast injection requirement of engine,a new-type common rail injector with double inlet fuel cavities was researched.The injector model was built based on AMESim software and was corrected through EFS test data.The results show that the new-type injector can realize the injection law presenting boot shape easily.Compared with current common rail injector,the shutting speed of needle valve for the new-type injector accelerates by two times and the flow area of inlet hole for fuel cavity decreases by 50%.The injection response improves with the decrease of fuel cavity volume and the recovery of slide valve improves with the increase of pre-tightening force of valve spring.Therefore the multi-injection capacity of the new-type injector improves.Accordingly,the injector can meet the performance requirements of different engines.Due to the effect of side fuel passage,the machining error of injector has little influence on injection consistency under the conditions of single structure and single injection.