Transient flow field characteristics of scraper pump based on viscosity wall strategy

This study presents an innovative scraper pump design. The design utilizes the synchronized movement of the upper and lower scrapers of the rotor to adjust the cavity volumes on either side, facilitating efficient fluid transfer. Unlike previous studies, scraper pumps face the challenge of dynamic contact between the scraper and the rotor due to their unique structure. A viscous wall strategy was employed to address hydrodynamic challenges at the point of contact, significantly improving performance prediction accuracy. The experimental data verified the accuracy of the simulation model, and the mass flow rate deviation between the simulation results and the experimental results was maintained within 10% when the viscosity at the contact point was set to 40 times the original medium viscosity. In addition, the study examined the effect of different operating speeds and load pressures on the pump performance. The results indicated that the outlet flow rate decreased by 22% when the pressure was increased from 2 MPa to 10 MPa and increased by 88.24% when the speed was increased from 900 r/min to 2200 r/min. These quantitative analyses provided valuable insights into optimizing scraper pump design and offered clear guidance for improving hydraulic performance and operational efficiency.