大型低扬程泵装置优化设计与试验

Optimum hydraulic design and model test of large-scale low-lift pump devices

为了对配置肘形进水流道和虹吸式出水流道的立式泵装置进行深入的研究,得到一种高效的立式泵装置,在肘形进水流道和虹吸出水流道型线数学模型基础上,开发了基于流道设计参数的优化设计软件,能快速进行流道型线的绘制,使流道的型线自动符合一维流速渐变的原则,并对虹吸出水流道的最优驼峰位置进行了理论分析。结合计算流体动力学技术,对待建的某大型低扬程泵站进行了肘形进水流道和虹吸出水流道的优化设计,得到了水力性能优良的进出水流道型线方案。根据泵装置水力模型比选试验,优选出了效率高、高效运行范围宽、无不稳定运行区、汽蚀性能好的高比转数导叶式混流泵211-80模型,在配置优化了的进出水流道的基础上使泵装置在扬程5.4m时模型装置效率达到了79.62%。该泵装置的优化设计方法与试验结果对相同装置型式的大型低扬程泵站建设具有重要的参考价值。

Based on the mathematical models of the geometric contours of elbow inlet passage and siphon outlet conduit,the general software for hydraulic optimum design was developed with the geometrical parameters,and the geometric contours of elbow inlet passage and siphon outlet conduit could be drawn quickly in accordance with the principle that the average flow rate was gradually changing.,and the optimum hump section of the siphon outlet conduit was theoretically analyzed.The hydraulic design of elbow inlet passage and siphon outlet conduit were optimized by the combination of one-dimensional design theory and the computational fluid dynamics （CFD） technique.For selecting an execellent model pump,detailed model tests of pump device were carried.Therefore,a high specific speed vane-type mixed-flow pump 211-80 model with high efficiency,good anti-cavitation performance and no instability running area was gained in the end.The pump device with the 211-80 model worked in a wide high-efficiency zone,and its maximum efficiency reached 79.62% at the net lift of 5.4 meters.The optimum design methods and model test results can offer the reference in large low-lift pumping station constructions.