Optimal Design Schemes of Centrifugal Pump Compound Impeller at Super-Low Specific Speed

The paper has established sixteen design schemes for super-low specific speed centrifugal pump compound impeller with orthogonal method, based on the main factors impacting the design of compound impeller, like short blades number of compound impeller, the relative position of blade radial inlet, blade circumferential bias degree, deflection angle, etc.,. By numerical simulation, the optimal design scheme has been determined. Compared with the method of permutation and combination, the optimal design scheme can greatly reduce the workload of the designers. In the meantime, by applying the orthogonal method for compound impeller design, the compound impeller internal pressure and velocity field distribution become quite reasonable, the curve H Q − is more flat, the Q η− curve excurses to the big flow, and also the work performance is fairly good.