Abstract: In this work, a RNG k-ε turbulence model is used to simulate the flows inside a canned motor, and flows in its stator section are calculated using a porous media model and the Ergun equation. We construct a theoretical model for hydraulic loss analysis based on energy conservation, and use it to reveal the time evolution of the motor’s hydraulic loss. Flow patterns are analyzed in details. The results show that spiral flow patterns occur in the gap between the rotor and porous medium, and the impacting water flow forms multiple axisymmetric vortices in this gap, which are attributed to the larger resistance in the porous medium. Near the thrust bearing, some axisymmetric vortices similar to the blade flow are located at its radial flow channel inlet, and high-vorticity circulating flows develop in the flow outside of it. These findings suggest a complex geometric structure may result in more vortices and cause a significant hydraulic loss, especially between the thrust bearings and sliding bearings. This study would be a useful reference for optimizing the geometric parameters and structure of related motors.

Key words: porous media flow, hydraulic loss, vortex, thrust bearing, canned motor