Heat Transfer Inside an Electric Motor

Abstract

Convection heat transfer from an axial air flow inside the gap between the rotor and the stator of a four-pole surface permanent magnet (SPM) electric motor has been investigated. All surfaces considered smooth with heat is being generated within the rotor while the stator is considered insulated. This study has been carried out numerically using ANSYS-CFX. The effect of the axial flow and rotational speed on the average Nusselt number has been investigated in terms of the axial and rotational Reynolds numbers in the range of 2140-6420 and 1750-27000, respectively. Numerical results have been validated using experimental data and found in reasonable agreement. Results show that the effect of the axial Reynolds number is more dominant than that of the rotational Reynolds number.