Experimental and numerical study of reverse power generation in coastal axial flow pump system using coastal water

Abstract

Coastal areas require frequent drainage to prevent waterlogging, and are often equipped with axial flow pump systems to enable this. Reverse power generation from CAPS (coastal axial flow pump systems) using coastal water is an untapped but high-potential source of renewable energy. However, the design of CAPS usually considers only the pumping conditions; there isa huge difference in flow during the reverse power generation condition (TC) and the conventional pumping condition (PC). If such a CAPS were to operate under TC, there would be unknown risks to its hydraulic performance and operational stability. In this study a special experimental test bench is built for the evaluation of CAPS. Energy test and measurement of internal pressure field are carried out for TC and PC of CAPS under full flow condition. Then, the energy loss characteristics and the propagation law of CAPS under PC and TC are investigated by an unsteady numerical simulation, and the results of the simulation are compared with the experimental results. The flow field difference between the PC and TC is analyzed in detail, and the hydraulic performance, operation safety, and stability of CAPS under TC are evaluated. This paper is expected to be of reference value for the renewable utilization of low-head water resources in coastal areas.