Effect of Tip Clearance on Hydraulic Performance of Water jet Pump
The k o Shear Stress Transport (SST) turbulence model is adopted to study the hydrodynamic performance of the water jet axial pump which is applied in Unmanned Surface Vehicle (USV) The numerical simulation of the whole passage of the water jet pump is carried out for four different tip clearance with d 0.3 mm, d 0.8 mm, d 1 mm and d 1.4 mm. And the results, in term of external characteristics and internal flow field, show that, due to the tip leakage flow, the leakage vortex is formed behind the blade after the fluid flows over the impeller blades. Moreover, with the expansion of tip clearance, the head and efficiency of the water jet pump will be affected, and this impact is weakened with the increase of the flow rate. Finally, the suggestion of structure optimization of water jet pump can be made.