Analytical Methods and Verification of Impeller Outlet Velocity Slip of Solid–Liquid Disc Pump with Multi-Type Blades

The intensive exploration to improve the accuracy of the calculation model of velocity slip and theoretical head has always been a major issue in pump research. Discontinuous blade of disc pump is different from the continuous blade of traditional pump. Disc pump realizes energy transfer by the effect of boundary layer. In order to fill in the theoretical blank of current research on the velocity slip and theoretical head of blade disc pump, the velocity slip is calculated by the systematic analysis under solid–liquid flow. In this study, the current misconception of velocity slip was corrected. Based on the different normal velocity components between particle and liquid on the blade surface, a new method is proposed to further verify the difference of solid–liquid flow velocity in impeller passage. Through the proposed method of calculating average circumferential velocity, the calculation model of the velocity slip coefficient and theoretical head of disc pump with linear and curved blade are given and verified. The accuracy of calculation model is increased by 39.4%. This model has good application value in theoretical head calculation, which lays a foundation for further research on energy conversion, energy efficiency prediction and reverse optimization design of disc pump with different blade shapes.