超高压共轨系统特性及其压力波动消除研究

摘要

To achieve an ideal fuel injection and improve the performance of diesel engine under vari-ous operational conditions,a concept of ultra high pressure common rail system is proposed.On the basis of introducing the configuration and working principle of this system,a simulation model is built up to verify the pressurization capacity and flexible fuel injection rate of the ultra high pressure com-mon rail system.The simulation results show that there is an obvious pressure fluctuation in pressuri-zation chamber of electric-controlled pressure amplifier.A method for eliminating pressure fluctuation is put forward to avoid the influence of pressure fluctuation on working stability of the injector.The results show that the pressure fluctuation is obviously weakened by adding a small rail cavity between electric-controlled pressure amplifier and injector,and the pressure fluctuation ends 10 ms earlier.%为实现更加理想的喷油规律,改善柴油机在各种运转工况下的经济性和排放性,提出了超高压共轨系统的概念.在阐明系统的结构组成和工作原理的基础上,建立了系统仿真模型,并利用模型验证了超高压共轨系统增压能力以及灵活喷油率的实现效果,仿真结果表明:系统电控增压器的增压室内存在明显的压力波动现象.为避免压力波动对喷油器的工作稳定性产生影响,就如何消除压力波动进行了研究,研究结果表明:采用在电控增压器与喷油器间加装小轨腔的方法对压力波动有明显的削弱作用,可以使压力波动提前10 ms结束.