具有壅塞环的空化器特性数值分析

摘要

Cavitating flow in choking pipe changes violently under chocking cavitation. Using the computational fluid dynamics software of Fluent, the standard k- model and multiphase flow cavitation model, mode numerical simulation on the cavitator with choking ring under different inlet velocity and back pressure conditions, analyzed the distributions of static pressure and void ratio in cavitation area when the choking ring at different position. The results show that choking ring can prompt the back pressure of the down stream of choking cross, and the farther choking ring from the annular nozzle exit is, the more obvious the effect is. The choking ring can increase the range of optimum back-pressure generating choking cavitation, and the closer choke ring from the annular nozzle is, the pressure range of cavitating flow bigger is.%出现壅塞空化现象时，壅塞管内流场会发生剧烈变化。利用计算流体力学软件Fluent，采用标准模型k-和多相流空化模型，在不同入口速度和背压条件下对具有壅塞环的空化器进行数值模拟，分析空化器壅塞环在不同位置时，空化区域内静压力和空隙率的分布情况。试验结果表明：壅塞环可以增加壅塞截面下游的恢复压力，且壅塞环离环形喷嘴出口越远，作用越明显；壅塞环可以增大产生壅塞空化的最佳背压范围，且壅塞环离环形喷嘴越近，产生壅塞空化流动的背压范围越大。