气泡模型在喷油系统模型仿真中的应用

摘要

为了更准确预测喷油系统中压力脉动变化,引入了基于气泡溶解和析出的物理过程的气泡模型,将其应用到柴油机喷油系统模型中,并编制了喷油系统模型仿真程序.对含气率恒定和应用气泡模型的柴油机喷油系统分别进行仿真,并将仿真结果与试验数据进行了对比.对比结果表明:含气率恒定的喷油系统模型仿真结果曲线比较平滑,而应用了气泡模型的喷油系统模型中,由于气泡体积随着系统压力和时间而变化,尤其在压力大于45 MPa后,气泡体积减小速度增大,造成压力出现震荡,仿真结果和试验数据更加吻合.该研究不仅验证了气泡模型应用在柴油机喷油系统仿真中的可行性,而且为以后气液两相条件下的柴油机喷油系统模拟研究提供了基础.%In order to predict pressure fluctuation of the diesel fuel injection system accurately, the gas bubble model based on gas bubble resolving and releasing physical processes was applied to the diesel fuel injection system model,and simulation program of diesel fuel injection system model was presented. The diesel fuel injection system model with the constant void fraction and the gas bubble model were simulated respectively, and the simulation results were compared with experimental data. The results showed that the simulation result curve of the diesel fuel injection system model with constant void fraction was smooth. But for the model of fuel injection system simulation with gas bubble, the simulation result was more coherent with the experimental data because the gas bubble volume varied with system pressure and time, particularly when the pressure exceeded 45 MPa, and the increasing of reduction rate of gas bubble volume caused the pressure shock. The study not only verifies the application feasibility of gas bubble model in diesel fuel injection system, but also provides reference for diesel fuel injection system model under two-phase condition.