无轴轮缘推进器的间隙流动功耗与散热

针对间隙流体的摩擦功耗及其对电机散热的影响问题,利用流体计算软件FLUENT计算不同结构参数和工况参数下间隙内的摩擦扭矩变化,并与经验公式得出的结果进行对比分析,结果显示两者相吻合。对考虑电机发热因素间隙流体的温度场分布进行数值计算,分析不同参数对间隙流体温度分布的影响规律。研究结果表明:轴向和径向间隙尺寸越大,间隙流体摩擦功耗均越大,但增大间隙尺寸对电机散热有利,因此间隙尺寸设计需综合考虑功耗、散热和磁场强度等;间隙尺寸和水流速度等是影响间隙流道温度场分布的关键因素,推进器工作产生的推力导致转子轴向移动,间隙流道功耗随之增加,温度场分布也发生变化。

Power Consumption and Heat Dissipation of Gap Flow in Shaftless Rim-driven Thruster

Aiming at the problem of the influence of friction power loss in the gap flow on the motor cooling, the friction torque change in the gap under different structural parameters and different working conditions are calculated by flow software FLUENT. The results are analyzed comparing with those from the empirical method. Both results show good agreement. Considering the motor heating, the temperature distribution in the gap is numerically calculated. The influencing law of different gap dimensions on the flow gap temperature distribution is analyzed. The results show that the friction power loss increases with the axial and radial gap sizes increasing. But increasing the gap dimension is benefit for the heat dissipation. Therefore, the gap dimension design should comprehensively consider the power consumption, cooling and magnetic density. The gap dimensions and flow velocity are key factors influencing the temperature distribution in the gap. The thrust generated from the thruster leads the rotor ring to move in axial direction. Then the power loss in the gap increases and the temperature distribution changes.