涵道风扇电机强迫风冷散热结构设计与实验

Design and Test of Forced Air Cooling Structure for Ducted Fan Motor

针对涵道风扇电机的轻量化高效散热需求,提出基于涵道风扇内部流场的强迫风冷散热方法,设计了肋片高度为3 mm、6 mm、9 mm和12 mm的四种风冷散热结构,应用工程估算和CFD方法对不同风速下散热效果进行对比分析,搭建实验平台开展地面试验验证。结果表明,在桨毂上增加散热肋片能够有效提高散热效率,壁面温升可降低至无肋片模型的74%、55%、44%、35%;对于轴向风冷,肋片能显著强化散热,但是存在温度不均的问题。工程估算和CFD方法对电机的带肋表面风冷散热分析有较好的精度,可用于涵道风扇电机的温升预示,为涵道风扇推进系统的使用提供依据。根据分析结果提出了高功率密度电机强化散热的研究方向。

Aiming at the lightweight and efficient heat dissipation requirements of ducted fan motors,a forced air cooling method based on the internal flow field of the ducted fan was proposed.Four kinds of fin air cooling structures with fin heights of 3 mm,6 mm,9 mm and 12 mm were designed.The heat dissipation effects under different wind speeds were analyzed using engineering estimation and CFD method,and a test platform was built to perform ground test verification.It showed that the heat dissipation efficiency was greatly enhanced by fin structures arranged on the outside of the hub,and the rise of wall temperature could be reduce to 74%,55%,44%and 35%of the finless model.For axial air cooling,fin could significantly enhance heat dissipation,but the temperature distribution in axial direction was uneven.The engineering estimation and CFD method have a good precision for the analysis of the heat dissipation of the ribbed surface of the motor,which can be used to predict the temperature rise of the ducted fan motor and provide valuable information for the application of ducted fan propulsion system.Further research direction of strengthening heat dissipation for high power density motor was proposed.