大型立式轴流泵装置泵工况及反向发电工况流道优化

Optimization of Flow Channel for Large Vertical Axial-flow Pump Device Under Both Pump Mode and Turbine Mode

泵装置是泵站的核心,开展泵装置优化研究非常重要。以轴向速度均匀度和速度加权平均角作为优化目标,实现对某大型立式轴流泵装置进出水流道在泵模式和反向发电模式下的全工况水力性能优化。通过对立式轴流泵装置的进出水流道进行多方案建模,在不改变进水流道起始面和出口断面形状的条件下,改变进出水流道弯肘段各个断面的尺寸及外侧型线,选取了不同进水流道和不同出水流道进行数值模拟结果的对比分析。细致分析了流道在泵模式和反向发电模式下叶轮进出口截面的流速分布均匀度、加权速度平均角度及进出水流道的水力损失、轴流泵装置外特性性能等指标的变化规律。研究成果表明,在泵站泵装置设计阶段,可以综合考虑进行流道在泵工况和反向发电工况下的水力设计来提高泵装置多种运行模式下的水力性能。研究成果为泵站泵装置水力设计和优化提供了理论支撑和工程实践参考。

Pump device is the core of pump station,it is very important to carry out optimization research of pump unit.Taking the uniformity of axial velocity and the weighted average angle of velocity as optimization objectives,the hydraulic performance of inlet and outlet channels of a large vertical axial flow pump under pump mode and reverse power generation mode was optimized under all working conditions.Through the multi-scheme modeling of the inlet and outlet flow channels of the vertical axial flow pump device,the size of each section and the outer inverted line of the elbow section of the inlet and outlet flow channels were changed without changing the initial surface and the shape of the outlet section.The numerical simulation results of different inlet and outlet flow channels were compared.The distribution uniformity of flow velocity at inlet and outlet section of impeller,the average angle of weighted velocity,the hydraulic loss at inlet and outlet channel,and the variation rule of external characteristics and performance of axial flow pump device were analyzed in detail under pump mode and reverse power generation mode.The research results show that the hydraulic design of the flow channel under pump condition and reverse power generation condition can be considered comprehensively to improve the hydraulic performance of the pump unit under various operating modes in the design stage of the pump device for pump station.The research results provide theoretical support and engineering practice reference for hydraulic design and optimization of pump device in pump station.