电动静液作动器热力学建模方法及油液温升规律

电动静液作动器（EHA）是多电飞机关键子系统之一，其高度集成设计在减小体积和质量的同时，大幅降低换热能力，导致EHA油液温度过高、功能丧失。针对目前EHA一维热力学建模不足问题，以油冷电机驱动的EHA为研究对象，提出EHA的“三维+一维+三维”的热力学建模方法。首先，分析EHA能量转换及传递规律，探究EHA热能产生和扩散途径，在考虑参数时变基础上提出EHA的“三维+一维+三维”热力学建模方法；其次，基于ANSYS平台建立EHA电机生热和壳体对流换热的三维热力学模型；然后，建立柱塞泵、液压缸、阀和增压油箱等一维热力学模型；最后，在AMESim平台上搭建EHA的“三维+一维+三维”的热力学模型。仿真和实验验证了EHA的“三维+一维+三维”热力学建模方法的正确性，揭示了EHA油液温升规律，为EHA的热设计提供了理论依据。 

A thermodynamic modeling method of electro-hydrostatic actuator and law of oil temperature rise

Electro-hydrostatic actuator (EHA), one of the key subsystems in the more electric aircraft,can reduce the size and weight of airborne equipment because of its highly compact design. However, the heat dissipation is weakened simultaneously, which can easily lead to an extremely rapid temperature increase and loss of function. In view of the drawbacks of traditional 1D thermal model, a “3D-1D-3D” thermal modeling method was proposed in order to research on the temperature rise of EHA driven by oil-cooled motor. Firstly, the conversion and transfer of energy in EHA were analyzed, aiming to find out the heat source and its diffusion. Further, the “3D-1D-3D” thermal modeling method was proposed considering that the parameters varied with time. Secondly, the 3D thermal model of EHA motor was established in ANSYS including the heat generation module and dissipation module, while the other components, for instance piston pump, hydraulic cylinder, valves, pressurized tank, etc., were studied with 1D thermal models. Finally, the whole “3D-1D-3D” thermal model of EHA was integrated on AMESim platform, and validated by experimental results. The results from simulations and experiments reveal the law of temperature rise in EHA, which provides the theoretical guidance for thermal design of EHA.