Method of Improving Efficiency of Low Specific Speed Centrifugal Pump

Aiming at the mechanical loss caused by shaft seal,bearing,impeller disk friction and the hydraulic and volume losses resulting in low efficiency of super-low specific-speed centrifugal pump,five kinds of methods are put forward to improve the efficiency of super-low specific-speed centrifugal pump,such as increasing pump speed,choice of larger blade outlet setting angle,increasing blade outlet width,appropriately increasing throat area of pump body,adopting composite blade combined with long and short blades.Experimental simulation method is used to verify the high efficiency of composite impeller pump and the results show that the energy-saving effect is remarkable;meanwhile the efficiency of composite impeller pump is higher 5.69-10.34 percent than that of ordinary impeller pump with four blades,which increases from 43.80 percent to 49.49-54.14 percent.