11018 Heat removal characteristics in rotating coaxial cylinders with slits simulated an electric vehicle motor

Toward the improvement of performance of the electric vehicle (EV), the design of the motor shape appropriate to heat removal is required. A typical EV motor is composed of the pair of coaxial cylinders with the fixed outer cylinder (i.e., stator) and rotating inner cylinder (i.e., rotor). Furthermore, the EV motor may have axial slits on the stator inner wall. Hence, the aim of the present study is to clarify heat removal characteristics in rotating coaxial cylinders with slits simulated an EV motor. The flow behavior in slits was measured via PFV with fluorescent particles distributed in the water, and the heat transfer between the stator and rotor was numerically examined. The results show that the vortex flow is observed in the slits, and the heat transfer between the stator and rotor is affected by the vortex flow.