Centrifugal pump hydraulic design task

Centrifugal pump over-current part mainly includes the suction chamber, impeller and pressurized water chamber. Centrifugal pump hydraulic design of the basic tasks are: According to given the head, flow, NPSH, efficiency and other design parameters, design a good energy and cavitation characteristics of the centrifugal pump flow components shape, one of the most critical components is impeller. 1, inhalation room generally has three forms: 1), tapered tube suction chamber. For small single-stage single-suction cantilever centrifugal pump, the structure is simple, easy to manufacture, the role of the impeller in front of the flow caused by the flow and accelerate the flow, so that flow uniformity, loss reduction. 2), spiral suction chamber. This suction chamber flow better, more uniform speed, but the flow into the impeller pre-rotation, to a certain extent, will reduce the head, but for low specific speed pump, this effect is not obvious. At present, China's cantilevered centrifugal oil pump and open multi-stage volute are used in this suction chamber. 3) annular suction chamber. The structure of the suction chamber is simple, the axial size is short, but before the flow into the impeller impact and vortex loss, the flow is not uniform, commonly used in multi-stage centrifugal pump. 2, there are three types of impeller: 1), closed impeller. Front and rear covers, runners are closed, high hydraulic efficiency, suitable for high-lift, suitable for conveying clean liquid. 2), semi-open impeller. Only the rear cover without front cover, the flow channel is semi-open, suitable for conveying liquids containing solid particles and impurities. 3), open impeller. No front and back cover, the flow channel is completely open, often used to convey slurry or pasty liquid.