隔板长度对紧凑型高速磁力泵水力特性及叶轮径向力的影响

为探究蜗壳内隔板长度对紧凑型高速磁力泵外特性与叶轮径向力的影响,根据蜗壳型式及隔板长度的不同提出6种蜗壳方案.设单蜗壳为方案一,其余双蜗壳方案根据隔板长度从小到大依次设为方案二至方案六.采用ANSYS-CFX软件对不同工况下(0.8Q_d,1.0Q_d,1.2Q_d)各蜗壳方案泵内流场进行数值模拟,得到不同蜗壳方案的泵中心面静压分布云图,并进行径向力分析.采用方案四蜗壳作为泵实型样机进行试验,将试验值与计算结果进行对比.研究结果表明:相较于无隔板的单蜗壳泵,采用有隔板的双蜗壳泵有利于平衡叶轮径向力,在额定流量下单蜗壳在x,y方向的径向力最大分量分别为151.2,149.7 N,是双蜗壳方案四的1.5倍;随着隔板长度的增大,泵的扬程与效率均逐渐提高,叶轮径向力不断减小,3种工况下扬程的模拟值与试验值偏差均小于3.0%;试验表明数值计算结果具有可信性,研究结果可为紧凑型高速磁力泵在提高水力性能以及平衡叶轮径向力方面提供一定参考.

Influence of baffle length on hydraulic performance and impeller radial force of compact high-speed magnetic pump

In order to investigate the influence of the internal baffle length to the hydraulic characteri-stics of the compact high-speed magnetic pump and the radial force of the impeller, six volute schemes were proposed according to the different length of the internal baffle. The single volute was set as scheme 1, and the remaining double volute schemes were set as scheme 2 to scheme 6 according to the length of internal baffle. ANSYS-CFX software was used to simulate and analyze the flow field in the pump with various volute schemes under different working conditions(0.8Q_d,1.0Q_d and 1.2Q_d). The static pressure distribution of the pump cross section plane with different volute schemes was obtained, and the radial force was analyzed. The scheme 4 was used as the prototype of the pump, and its calculation results were compared with the experimental results. The results show that compared with the single volute pump without baffle, the double volute pump with baffle is beneficial to balance the radial force of impeller. The maximum components of radial force of single volute in x and y directions are 151.2 N and 149.7 N respectively at rated flow, which is 1.5 times of that of scheme 4. At the same time, with the increase of baffle length, the head and efficiency of the pump gradually increases, and the radial force of the impeller decreases continuously. The deviation between the simulated and the experimental results of the head under the three conditions is less than 3.0%. The numerical simulation results are credible, which provides a useful reference for improving the hydraulic performance and balancing the radial force of the impeller for the compact high-speed magnetic pump.