水锤泵内部流道优化及性能研究

Flow passage optimization and performance study of the hydraulic ram pump

水锤泵是一种不用电和油的自动泵水机械,在缺电、无电的山区、农村具有广阔的应用前景。为解决传统设计过程中难以对流道进行评析、研发周期长以及产品性能低的难题,提出了水头损失系数、阀瓣升力系数、阀瓣受力偏心距和出口流速分布均匀度的水锤泵内部流道评价指标和相应的数学模型,建立了采用前扩式和后扩式流道的水锤泵数值模型,并进行了分析对比。前扩式和后扩式流道的水头损失系数分别为4.51和3.72,泄水阀的升力系数分别为4.11和2.23,泄水阀受力来流方向的偏心距分别为0.21 mm和2.02 mm,泄水阀出口的流速分布均匀度分别为47.8%和69.2%。经对比,后扩式流道的水头损失系数和泄水阀升力系数小,受力偏心距大,出口流速分布均匀度高,是一种较为合理的布置形式。选择后扩式流道制造生产了新型水锤泵,在不同作用水头和扬程下进行多工况性能测试,建立了扬水量评估公式,给出了所需的来水量。

The hydraulic ram pump, an automatic water-pumping device without any external energy input like electricity or oil, can be widely used in mountainous and rural areas short of power. To solve the is- sues of unavailable flow passage analysis, long development period and poor performance encountered with traditional means, evaluation indexes, including head loss coefficients, drag coefficients, eccentric distance of pressure on the waste valve and velocity uniformity of the outlet, were proposed as well as numerical models. Numerical models were established and compared with the front-expansion and back-expansion flow passage. The head loss coefficients are 4.51 and 3.72 respectively. The drag coefficients are 4.11 and 2.23, the eccentric distances of pressure on the waste valve are 0.21mm and 2,02mm and the velocity uniformity of the outlet are 47.8% and 69.2%. The back-expansion flow passage has lower head loss coefficient and drag coefficient, larger eccentric distance of pressure and higher velocity uniformity of the outlet than those of the former one. Therefore, the back-expansion flow passage was adopted in the novel hydraulic ram pump. Through numerous experiments of variable supply and delivery heads, the formula for the delivery flow was built and the inflow required was given.