杭州八堡泵站斜式泵装置流道水力优化

为保证杭州八堡泵站斜式泵装置的安全、稳定和高效运行,运用三维湍流数值模拟方法对该站斜式进、出水流道进行了水力优化设计研究.基于流道三维流场数值计算结果,揭示了进水流道高度和泵轴倾角分别对斜式进水流道水力性能的影响规律,揭示了出水流道平面扩散角和泵轴倾角分别对斜式出水流道水力性能的影响规律.结果表明:斜式进水流道高度愈大流道水力性能愈好,泵轴倾角愈小流道水力性能愈好;斜式进水流道转向角度愈小,水流受离心力影响愈小,愈有利于水流流动调整;斜式出水流道扩散角愈小流道水力性能愈好,泵轴倾角愈大流道水力性能愈好;受螺旋状的水流和急剧转向的“S”形弯曲流道的共同影响,斜式出水流道内不可避免地存在不对称旋涡;综合考虑八堡泵站流道水力性能、土建工程量、闸门提升高度和水泵机组安装检修难度等多方面的因素,确定该站斜式泵装置的泵轴倾角为20°.

Conduit Hydraulic optimization of the slanted pump system for Babao Pumping Station of Hangzhou

In order to ensure the slanted pump system of Babao Pumping Station to operate safely, reliably and efficiently, the optimum hydraulic design on the station′s slanted inlet conduit and slanted outlet conduit has been completed by the method of three-dimensional turbulent flow numerical simulation. Based on the numerical simulation results, the influences of conduit height and pump shaft angle on the hydraulic performance of slanted inlet conduit were respectively studied and the influences of diffusion angle and pump shaft angle on the hydraulic performance of slanted outlet conduit were respectively studied. The results indicate that the larger the height of the slanted inlet conduit, the better the conduit hydraulic performance; the smaller the angle of pump shaft, the better the conduit hydraulic performance; the smaller the turn angle of inlet conduit is, the smaller the influence of centrifugal force is, and the more advantageously the flow adjusts; the smaller the diffusion angle of slanted outlet conduit, the better the conduit hydraulic performance, the larger the angle of pump shaft, the better the conduit hydraulic performance; affected by both the spiral flow and the S-shaped curving conduit which turns sharply, the asymmetric vortex exists inevitably in slanted outlet conduit; comprehensive consideration on the various factors of Babao Pumping Station such as conduit hydraulic performance, civil engineering quantity, hoisting height of sluice gate and installation and maintenance difficulty of pumping unit, the angle of pump shaft is determined as 20° for the slanted pump system of the station.