Pump Performance Prediction with Tip Clearance in Screw-Type Centrifugal Pump

摘要

An impeller of a screw-type centrifugal pump has a conical hub cone with one 3-D spiral blade. The influence of the tip clearance on the pump performance has not been clarified yet because of its complicated configuration. In the present study, the pump head and the efficiency were predicted numerically and compared with the experimental results. Due to the tip clearance along the long spiral blade, the tip clearance was not kept constant in the experiment. The numerical simulations have been carried out under the condition with four kinds of constant tip clearances. The numerical results of the pump head agreed well with the experimental results. The torque calculation was conducted by considering disk friction of the impeller back shroud and mechanical loss. The difference of pump efficiency between the prediction and the experiment was less than 10% with neglecting mechanical loss. Besides, flow patterns with different tip clearance were compared.