叶片进口安放角对离心泵性能影响

Influence of Blade Inlet Angle on Performance of Centrifugal Pump

为全面了解进口安放角对离心泵性能的影响,在型号为DFG150-9离心泵叶轮水力模型基础上添加正负冲角,获得6组叶片模型,利用RNGκ-ε模型考虑湍流影响,采用均质多相模型和Rayleigh-Plesset方程考虑空泡生长和溃灭,对6组模型进行三维定常湍流数值模拟,并对效率、扬程和空化余量等进行预测和对比分析。结果表明,添加负冲角,泵效率下降很多,效率曲线向小流量方向偏移,且加速泵抗空化性能恶化;添加0°～15°冲角,所加正冲角越大,小流量区效率越低,大流量区效率越高,且效率曲线向大流量方向偏移,对泵空化性能影响不明显;当正冲角添加至20°时,泵抗空化性能急剧下降,泵效率下降很多。

For comprehensive study of the impact of inlet angle on cavitation performance, based on a hydraulic model of DFG150-9 centrifugal pump, the positive and negative incidence angles are added to the impeller and six group blade models are obtained. RNG k-e model is adopted to consider the impact of turbulence. Homogeneous multiphase model and Rayleigh-Plesset equation are used to consider cavity growth and collapse. Three-dimensional steady turbulent flow is nu merically simulated for the six group models. The efficiency, water head and cavitation residue are predicted and compared. The results show that when adding a negative incidence angle, the pump efficiency decreases too much, efficiency curve shifts to the direction of small flow and it accelerates the deterioration of the pump anti-cavitation performance; when adding a positive angle among 0°-15°, if the angle is larger, the efficiency is lower in the small flow area while higher in the large flow area and efficiency curve shifts to the direction of large flow, it has little impact of pump anti-cavitation performance; when adding the positive angle to 20°, pump anti-cavitation performance has a sharp decline and the pump efficiency decreases too much.