导叶位置对S型轴伸贯流泵装置水力性能的影响

为了研究不同导叶位置对S型轴伸式贯流泵装置水力性能的影响,设计了4种不同导叶相对位置的方案,并分别针对小流量(Q=0.8Q0)、设计流量(Q=1.0Q0)、大流量(Q=1.2Q0)3种工况下的S型轴伸贯流泵装置进行了数值模拟计算。对比数值模拟结果与试验结果,并分析计算结果的外特性与内特性,通过模型试验验证了数值模拟计算结果的准确性。结果表明,泵装置效率和扬程随导叶相对位置逐渐增大呈现先上升后下降的趋势,导叶与叶轮之间的相对距离存在最优值A=10 mm,在此位置时,泵装置效率和扬程相对最高,导叶体水力损失与出水流道水力损失相对最小,导叶体对于动能的回收能力强。小流量与设计流量工况下,出水流道进口平均涡角的大小随导叶相对位置先减小后增加,对应出水流道水力损失先下降后上升的趋势。大流量工况下,平均涡角不随导叶相对位置变化而变化。

Effect of the Position of Guide Vane on Hydraulic Performance of the S-shaped Extension Pumping System

The influences of guide vane position on hydraulic performance of the S-shaped extension pumping system were studied in this paper numerically. We considered four positions and three flow conditions:designed flow (Q0), reduced flow (0.8Q0) and fast flow (1.2Q0). The results showed that with the relative position ofthe guide vane increasing, the efficiency and lifting height of the pump increased first before declining. The optimal relative distance between the guide vane and the impeller was 10 mm at which the energy loss in both the impel-ler body and the outlet passage was minimal, the pump efficiency and lift height peaked, and the guide vane was most effective in recovery of the kinetic energy. Under the reduced and designed flow rates, the average inlet vor-tex angle of the outlet passage and energy loss at the outlet passage decreased first before increasing. Under high flow rate, in contrast, the average vortex angle remained constant, independent of the relative position of the guide vane.