Optimal design and performance analysis of hydraulic ram pump system

Abstract

Hydraulic ram pump is an automatic water-pumping equipment generally used to pump drinking and irrigation water in mountainous and rural areas having short of power. In the past, it has been analyzed and optimized by fabricating various prototypes and conducting experiments and comparisons. This process is time and labor consuming and detailed flow features cannot be determined except efficiency, discharge, and period. In this paper, a method for the optimal design and performance analysis of hydraulic ram pump system with numerical simulation and physical experiment is presented to shorten the number of prototypes and develop high-performance product. The proposed evaluation indexes include head loss coefficient, drag coefficient, eccentric distance of pressure, and velocity distribution uniformity. Two types of structures, named front-enlargement and back-enlargement, were initially designed. According to the numerical simulation, the latter one has lower head loss coefficient and drag coefficient, larger eccentric distance of pressure and higher velocity distribution uniformity and was adopted in the novel hydraulic ram pump. Then, the design theory and method on adjustable and high-head experimental platform have been developed, so that the delivery head can be easily controlled and regulated in laboratory. Experiments were carried out for the delivery heads of 2.0 m and 2.7 m and comparisons were conducted with other products. The results show that, when the delivery head is less than 50 m, the efficiency of the new product ranges from 50% to 70% while the delivery flow is the largest. Its application in Liangshui River, Beijing, indicates that the novel hydraulic ram pump is a practical tool in fountain sight and for irrigation purpose without external power input.