高扬程大流量离心泵CFD水力优化设计

选哈电A934模型叶轮作为对象叶轮,以预定的泵扬程流量特性(H-Q)为目标参数,在保证出口角不变的情况下,将对象叶轮出口直径延拓到目标叶轮直径,形成待优化的目标叶轮．使用CFX-TASCFlow软件进行改型设计,针对干河泵站最大扬程、最小扬程以及设计扬程对应的工况点,优化叶轮的轴面形状、叶片数量、叶片翼型以及进出口安放角等参数,直至CFD预测的H-Q特性接近或达到预期的目标,获得满足目标参数的目标叶轮．在此基础上,使用Ansys CFX对目标叶轮进行全通道水力设计,优化流道几何参数,匹配进水管、固定导叶以及蜗壳的几何形状,改善泵进出口区域的流场特性．在哈尔滨电机厂有限责任公司高水头试验II台上进行的模型试验表明,基于CFD技术开发的新型高扬程大流量离心泵在高海拔地区复杂工况条件下,扬程、流量、效率、空化性能等指标均达到了预定的设计目标．

Hydraulic design optimization of centrifugal pump with high head and large capacity by using CFD

The impeller of hydraulic model HEC A934 was used as an initial impeller for the centrifugal pump to be developed, and its diameter was enlarged to an expected value while the outlet blade angle kept unchanged, then the impeller geometry is going to be optimized. The meridian flow channel shape, number of blades, blade section profile, inlet and outlet blade angle and so on were altered according to the lowest, design and highest head specified by the pump user, the performance of those impellers was estimated by means of CFD code CFX-TASCFlow to examine if the expected head flow rate curve has been achieved; if not, the alteration will be continued until an impeller with best performance is obtained. Further, the flow in the pump with this optimized impeller was simulated by using Ansys CFX to check if the suction entry, guide vane and volute casing have matched the impeller. Finally, the corresponding model pump was measured on the high head test system II in HEC. It was confirmed that all the hydraulic parameters, namely, head, flow rate, efficiency, cavitation number etc have met the target values.