入口导流栅几何参数对高速泵诱导轮空化特性的影响

高速离心泵空化问题机理相对复杂，通常认为诱导轮间隙泄漏涡与回流漩涡是影响高速离心泵空化的主要原因。本文通过在诱导轮入口前增设导流栅来抑制旋转涡，达到提高离心泵空化性能的目的。采用RNG k-ε湍流模型，对带有矩形、椭圆形两种不同形状导流栅的离心泵进行全流场模拟，分析高速离心泵全流场数值计算结果，对比增置导流栅前后离心泵空化特性以及进口段流场。结果表明:带椭圆形导流栅的离心泵临界空化数有所降低，空化性能得到改善；增设导流栅后，诱导轮进口段旋转强度明显减弱，离心泵扬程均有明显提升，其中椭圆形导流栅方案较原方案提高了3%。

Influence of Geometric Parameters of Inlet Diversion Grid on Cavitation Characteristics of High-speed Pump Inducer

The mechanism of the cavitation problem of high-speed centrifugal pumps is relatively complicated. It is generally believed that the leakage vortex and return vortex of the inducer gap are the main reasons. In this study, a diversion grid was added before the inlet of the inducer to suppress the swirling vortex and achieve the purpose of improving the cavitation performance of the centrifugal pump. The RNG k-ε turbulence model was used to simulate the full flow field of a centrifugal pump with two different shapes of rectangular and elliptical diversion grids, and analyze the numerical calculation results of the full flow field of the high-speed centrifugal pump, and compare the cavitation characteristics of the centrifugal pump and the flow field in the inlet section before and after the installation of the diversion grid. The results show that the critical cavitation number of the centrifugal pump with elliptical diversion grid has been reduced, and the cavitation performance has been improved. After the addition of the diversion grid, the rotation strength of the inducer inlet section was significantly weakened, and the lift of the centrifugal pump was significantly improved. The elliptical diversion grid plan increased by 3% compared with the original plan.