Abstract：The dynamic properties of pump annular seals can be improved by modeling on the cylindrical sealing surface. To improve the stiffness characteristics, a new spiral grooves modeled on the cylindrical surface of annular seals was proposed. Considering cavitation the CFD method was used to simulate the internal flow of annular seals, and the small annular eccentricity was ensured by the moving mesh technology. The influence of spiral grooves on the flow characteristics was studied and comparatively analyzed with that of smooth annular seals. The results show that the spiral grooves can generate dynamic pressure effect and pumping effect. The low and the high pressure zones appear at the sharp corners of stair and dam side respectively. With eccentricity, the spiral grooves can enhance stiffness and reset force with reduced offset angle, which indicates that the spiral grooves is helpful to acquire better rotor concentricity. The spiral grooves can also obviously reduce the leakage and slightly increase the frictional torque. The spiral grooves is beneficial to improve the hydrodynamic characteristics of annular seals and the performance of rotor concentricity, which can also reduce the friction and wear.
2019, Vol. 40 
