胥浦活水泵站肘形进水流道流态分析及优化

胥浦活水泵站为一座长江边低扬程引水泵站,设计流量5.0 m3/s,最大扬程3.3 m。为适应其低扬程、小流量的特点,选用了全贯流潜水泵,在原胥浦节制闸底板上改建安装。为了保证在长江低水位时,水泵进水口完全淹没,进水流道型线平顺,流道内无涡带或其他不良流态,机组启动正常和运行稳定,利用三维数值建模、边界条件设置与三维湍流流动模拟,运用计算流体动力学CFD方法,进行进水流道内部流动数值模拟,多方案分析和比较进水流道内部流态、水泵进水条件和流道的水力损失。计算结果表明,进口尺寸1.1 m×3.4 m(高×宽),出口直径1.2 m的型线B方案进水条件好,流道水头损失小,满足水泵高效运行的要求。优化设计方案为泵站安全运行提供最优的设计进水流道型线和设计参数。

Flow pattern analysis and optimization of elbow inlet conduits of Xupu running water pumping station

Xupu running water pumping station is a low head pumping station near the Yangtzi River， with a design discharge of 5 m3/s and a maximum head of 3.3 m. Considering its characteristics of its low head and small discharge， the submersible tubular pump is selected in the practice. The pump is reconstructed and installed on the original Xupu regulating sluice soleplate. Its inlet conduit bottom board and the original sluice plate have the same elevation and the hydrological data are unchanged. It should be ensured that when the Yangtze River is at low water level, the water inlet conduit of the water pump is submerged fully and the inlet conduit line is plain sailing. No vortex or other undesirable flow patterns should occur in the flow conduit， and the unit should start normally and operate steadily. In this paper, by adopting three-dimensional numerical simulation， domain parameter setting and three-dimensional turbulent flow simulation, and using the computational fluid dynamics method CFD, numerical simulation of internal flow inlet channel is made and comparison of inlet conduit internal flow and pump flow conditions is carried out, and the hydraulic loss of the inlet conduit in various schemes is analyzed. The analysis results show that the line-type B (having inlet size of 1.1 m×3.4 m and outlet diameter of 1.2 m) is in good inflowing condition, having a small head loss, and meeting the requirements of high pumping efficiency. The results can be used as a reference for the optimal design of inlet type line and for the safe operation of the pumping station.