Pumping Station Inflow - Discharge Hydraulics, Generalized Pump Sump Research Study

摘要

This report contains the first phase of a continuing sump research study for typical small pumping stations (capacities less than 200cfs) with relatively low submergences. The facility consists of three operational mixed-flow pumps and one suction of dummy pump. An automatic data acquisition system is housed in an environmentally controlled building. Comparison testing was conducted with an operational pump and the dummy pump. Optimum location of the pump within the sump was determined by a wide range of testing. Surface vortex suppressors and other appurtenance were tested to improve approach inflow conditions and diminish vortex action. The improved sump design with optimum pump location was used for repetitive test to determine base to plot performance 'signature' curves for each of the three operational pumps. The coordinates of these signature curves were installed in the permanent memory of the microcomputer for comparison of subsequent sump designs. An 0.8D- to 2-D-high vertical drop was located across the sump approach at varying distance from the pump. Test results showed only minor deviations from the signature data; when the distance was equal to or greater than 2D, the flow was in the lateral plane, and the submergence was equal to or greater than 0.47D. Criteria for similarity of surface vortices in pump station models are discussed using a search of the literature. Similarity of submerged vortices is investigated in physical models of different size. (fr)