MULTI-STATE CENTRIFUGAL PUMP

摘要

PROBLEM TO BE SOLVED: To achieve miniaturization and improvement of efficiency by improving the channel configuration of a guide impeller in a multi-state centrifugal pump provided with a plurality of impellers on the same rotary shaft. SOLUTION: The multi-state centrifugal pump provided with a plurality of impellers on the same rotary shaft comprises a guide impeller 5 in the channel linking the outlet port of an impeller of a former stage and the inlet port of an impeller of a latter stage. The guide impeller 5 has a back shroud 11 for partitioning between the impellers of the former and latter stages. The back shroud 11 comprises a guide vane 9 as a diffuser disposed outside the former and latter impellers, and a return vane 10 disposed in a circular blade-like arrangement in a channel 7 linking the guide vane 9 and the inlet of the former and latter impellers. The number of the blades of the guide vane 9 is larger than the number of the blades of the return vane 10, and the number of the blades of the return vane 10 is larger than the number of the blades of the impellers. The channel 7 is a free channel without a blade row so that mixing of flows is promoted by interference of a pressure pulsation generated by the guide vane 9 and the impellers so as to restrain the pressure pulsation. COPYRIGHT: (C)2009,JPO&INPIT