用无网格粒子法直接模拟多相多组分界面流

Direct simulation of interfacial flows for multi-phase and multi-component mixtures using the particle method

模拟了以下两个多相多组分含复杂界面变形的流动:在脉冲加速下的液滴破裂和突然减压下的闪蒸射流。采用了移动粒子半隐式法(MPS)直接数值模拟方法。MPS法是一种适用于不可压缩流体流动计算的无网格粒子法。结果表明液滴破裂的临界Weber数等于13,该值与Pilch和Erdman的实验值相吻合。对于闪蒸射流,射流由于表面闪蒸被剥离为锥状,且射流长度随着压力衰减比的增加而减少。这些特征与实验观察是一致的。这两种模拟的结果表明了MPS法在处理复杂界面流动计算中的优势以及其鲁棒性。这些结果对反应堆事故分析有意义。

Two complicated interfacial flows, drop breakup during impulsive acceleration and the flashing of liquid jets during sudden depressurization were analyzed numerically using the moving particle semi-implicit method, which is a gridless particle method applicable to incompressible flows. The critical Weber number for the drop breakup obtained is 13, which is in agreement with the Pilch & Erdman experimental value. The simulation results for the flashing liquid jet demonstrate that a cone-shape liquid core develops immediately downstream of the orifice exit and that the extinction length of the flashing jet decreases with increasing depressurization ratio. This behavior of flashing jets agrees well with experimental observations. The results show that the method can be used to efficiently analyze complex interfacial flows.