底部形式对一体化泵站水力性能CFD 影响研究

为探究一体化泵站不同底部形式对水力性能的影响,选取2台潜水轴流泵为研究对象,在一定流量条件下,基于CFD软件,分析泵站底部分别采用圆弧、椭圆、斜坡形式时的内部流动特性。由于底部形式的改变,导致泵吸水受影响,其中泵Ⅰ水力效率、进口流速均匀度高于泵Ⅱ 4%左右,泵Ⅰ进口加权平均角高于泵Ⅱ 1%~3%。底部形式为圆弧时,流态分布无明显差异,但两泵效率偏差相对较大。当圆弧半径为2.0 R时,流速均匀度与加权平均角有所增高,流态相对较好;在椭圆弧式底部形式下,流速分布较好,水泵效率较高,推荐选取椭圆弧半径为0.2 R;在斜坡底部形式下,随斜坡角度增加,易引起漩涡,流态发生恶化等,建议选取底部斜坡角度为30°。

Research on the Influence of Pump Bottom Forms on the Hydraulic Performance of Integrated Pumping Station by CFD

In order to explore the influence of different pump bottom forms on the hydraulic performance of the integrated pump station,this paper takes two axial flow pumps as the research object,under a certain flow condition,the influence of circular arc type,elliptical type and slope type on the flow characteristics of the integrated pump station is analyzed. Due to the change of bottom form and the influence of pump water absorption,Among them,the hydraulic efficiency and the uniformity of pump Ⅰ inlet velocity is about 4% higher than that of pump Ⅱ,and the weighted average angle of pump Ⅰ inlet is 1%~3% higher than that of pump Ⅱ. In the form of arc bottom,there is no obvious difference in the flow pattern distribution,but the efficiency deviation of the two pumps is relatively large. When the arc radius is 2.0 R,the flow rate uniformity and weighted average angle are relatively high,and the flow pattern is relatively good;in the form of ellipse arc bottom,the velocity distribution is good,and the pump efficiency is high,the radius of advancing ellipse arc is 0.2 R. In the form of slope bottom,with the increase of angle,it will cause vortex and even worsen the flow pattern. It is suggested to choose an angle of 30°.