Hydraulic Performance of a Box Culvert-Type Two-Way Channel Pumping System: An Experimental Study

With the increasing application of box culvert-type two-way channel pumping systems in low-head pumping stations along rivers in China, a comprehensive investigation of their hydraulic performance is of significant importance. In this study, a physical model test was conducted on a box culvert-type two-way channel pumping station located along the Yangtze River. The energy performance, cavitation characteristics, runaway characteristics, and pressure pulsation behavior of the pumping system were systematically examined. The experimental results indicate that the pumping system achieves optimal energy performance when the blade installation angle is −2°, under which the maximum system efficiency reaches 68.0% while satisfying the operational requirements across different head conditions. For a given blade angle, the critical cavitation margin of the pumping system initially decreases and subsequently increases as the head decreases. At the same head, the critical cavitation margin increases with increasing blade installation angle. Furthermore, the unit runaway speed of the pumping system increases as the blade angle decreases. The blade installation angle significantly influences the amplitude of pressure pulsations at the impeller, whereas its effect on the dominant frequency is relatively minor. The overall pressure pulsation amplitudes measured at the impeller are less than 0.20 m. These findings provide valuable experimental insights for the hydraulic optimization design and operational regulation of similar pumping stations, contributing to improved operational efficiency and reliability while reducing operating costs.