高压共轨燃油喷嘴空穴流动的非稳态模拟

Unsteady Simulation of Cavitation Flow for High Pressure Common-Rail Fuel Injector

建立了船用柴油机高压共轨燃油喷嘴空穴流动的非稳态计算模型,采用AMESim模拟计算结合高压共轨燃油系统平台试验的方法对高压共轨燃油喷嘴空穴流动进行研究。研究结果表明:该方法可以较为准确地确定燃油喷射过程中喷嘴内部的压力波动;非稳态模拟可以较好地反映燃油喷射压力的波动对喷嘴内部压力分布和喷孔中燃油喷射速度的影响;在高压喷射条件下,喷孔中形成挑射液流的空穴流态,燃油喷射压力的波动对其影响较小。

The unsteady calculation model of cavitation flow for high pressure common-rail fuel injector of marine diesel engine was set up. Then the cavitation flow for high pressure common-rail fuel injector was studied by the way of combining AMESim simulation with high pressure common-rail fuel injection system bench test. The results showed that： during fuel injection, the pressure fluctuation in injector could be exactly obtained by the method; the unsteady simulation could well reflect the effect of fuel injection pressure fluctuation on pressure distribution in injector and fuel injection velocity of nozzle hole ; in high pressure injection, the cavitation flow of hydraulic flip may be formed in nozzle hole, and the effect of injection pressure fluctuation on it was smaller.