A Mechanism for Suppressing Backflow Vortex at Centrifugal Pump Impeller Inlet

Abstract

Disclosed is a mechanism for inhibiting a backflow vortex of an impeller inlet of a centrifugal pump. A revolving-body choma of which the section is in an approximate L shape is added between a water inlet pipe of a pump and the impeller inlet. The L-shaped choma is fixedly connected to a pump body through a bolt. The head part of the bolt is flush with the end face of the L-shaped choma. An adjusting spacer is mounted between the pump body and the L-shaped choma. The inner side of the front edge of a front cover plate of an impeller is in a streamline shape. The impeller inlet and the L-shaped choma together form an annular gap of which the width is decreased gradually. The section of the annular gap is divided in to a front segment in a streamline shape, a middle segment in a trapezoidal shape and a transition segment in a rectangular shape. The impeller inlet faces towards the L-shaped choma. The front cover plate of the impeller and a choma arranged on the pump body form a gap. The inner diameter of the L-shaped choma is the same as the inner diameter of the water inlet pipe, and the water inlet pipe, the L-shaped choma and the impeller keep coaxiality.

Description

technical field [0001] The invention relates to the field of centrifugal pumps, in particular to a mechanism for suppressing backflow vortices at the inlet of impellers of centrifugal pumps. Background technique [0002] In the centrifugal pump, due to the centrifugal force generated by the high-speed rotation of the impeller, the uneven force of the blade on the liquid flow makes a pressure difference between the outer edge of the impeller inlet and the center near the shaft. Wherein, the pressure at the outer edge is higher than that at the inner edge, which causes the liquid at the outer edge of the blade to flow back into the suction pipe, thereby forming a backflow vortex. When the flow rate decreases, the return vortex generally first appears at the impeller inlet near the front cover. As the flow rate decreases, the strength of the recirculation vortex, the recirculation area, the speed of the reverse flow of the liquid flow and the intensity of the pre-swirl increas...

AI Technical Summary

Problems solved by technology

[0004] The present invention overcomes the above-mentioned shortcomings of the prior art, and proposes a mechanism for suppressing the reflux vortex at the inlet of the impeller of the centrifugal pump, which can effectively solve the problems of unstable operation and poor performance caused by the reflux vortex at the inlet of the centrifugal pump when it is working at a small flow rate.

Images