A numerical study on heat release characteristics on configuration of coolant passages in air vehicle motor

Heat characteristics of air vehicle motors are essential for the design of electric aircraft because of heat generation when air vehicle takes off. In this study, the numerical simulation of a water-cooled AFPM motor was carried out to obtain heat transfer characteristics. A simplified computational domain was adopted with coolant passages, and electromagnetic losses of copper, iron, and eddy currents were considered. The steady-state and incompressible flows were assumed to represent the cruising flying condition of the 150-kW power rating in the motor. The system pressure loss and coil temperature were analyzed by changing passage configurations in 4-partition cases. To resolve thermal imbalance, it is best to have the number of channel partitions increase upstream and gradually decrease as you go downstream. This study allows motor designers for air vehicles to evaluate various coolant passage configurations numerically in advance.