Research on regular pattern of gap flow in Shaftless Rim-driven thruster

摘要

Shaftless rim-driven thruster integrates the duct, the propeller, the motor and the bearings to form a complete propulsor. While thruster works underwater, there is water flow running through the gap flow channel due to pressure difference, resulting in additional friction power consumption in the gap, furthermore affecting the hydrodynamic efficiency of the propulsor. A 5.5kW shaftless rim-driven thruster model which adopts the above structure was built after offering the concrete gap structure and geometric parameters. The integrated computer engineering and manufacturing for computational fluid dynamics (ICEM CFD) was employed to mesh the model before it was calculated in fluent, a CFD software that is widely used. The effects of different gap ratio in radial and axial direction, speed and pressure on the gap flow field were analyzed. Results showed that friction torque increased with the gap, and friction torque in both axial and radial direction had mutual effects on each other, and the heat generated in motor dissipated quickly in gap flow .