立柱对大型泵站前池和进水池流态影响的数值分析

为了研究泵站工程前池内部流态对水泵机组的效率及水力稳定性的影响.以某大型泵站为研究对象,基于3种不同增设立柱方案对前池进行整流.研究结果表明:增设立柱对前池流态有较好的改善作用,并降低了吸水喇叭管进口及水泵进口处的涡量强度,有利于提高机组水力稳定性.在保证流动损失几乎不变的情况下,等间距单排方案、等间距双排方案与非等间距双排方案的流速分布均匀度分别提高了3.13%,3.91%和4.95%,平均偏流角分别减小了1.45%,2.11%和2.66%.非等间距双排方案计算的叶轮进口压力脉动强度较等间距单排方案显著降低,其脉动系数峰值由0.016减小为0.006.对比结果显示,非等间距双排方案在前池整流中有较大优势.因此在前池中增设非等间距双排立柱可使前池流速分布较为均匀.研究结果可为类似前池设置水力优化措施提供参考.

Numerical analysis on influence of vertical column on flow pattern in forebay and intake of large pumping station

In order to study the influence of flow pattern in forebay on the efficiency and hydraulic stability of pumping unit. This paper takes a large pumping station as the research object, and the forebay was rectified based on three different additional column schemes. The research results show that adding a column has a better effect on improving the flow pattern of the forebay, and reduces the vortex intensity at the inlet of the suction horn pipe and the water pump, which is beneficial to improve the hydraulic stability of the unit. Under the condition that the flow loss was almost unchanged, the uniformity of the flow velocity of equal spacing single row plan, equal spacing double row plan and non-equal spa-cing double row scheme are increased by 3.13%,3.91% and 4.95%, respectively, and the average drift angle was reduced by 1.45%, 2.11% and 2.66%, respectively. Furthermore, the result show that the intensity of impeller inlet pressure pulsation was calculated by the non-equal spaced double-row scheme is significantly lower than that of the equidistant single-row scheme, and the peak value of the pulsation coefficient was reduced from 0.016 to 0.006. The comparison results show that the non-equal spaced double row scheme has a greater advantage in the front pool rectification. Therefore, the velocity distribution in forebay can be more uniform by adding non equidistant double row columns. The research results of the study can be used as a reference for similar hydraulic optimization measures in forebay settings.