A research team led by Professor Wang Shaoping from Beihang University’s School of School of Automation Science and Electrical Engineering has made significant strides in addressing the thermal management challenges of oil-immersed electro-hydrostatic actuators. Their paper, titled "Cumulative thermal coupling modeling and analysis of oil-immersed motor-pump assembly for electro-hydrostatic actuator," was recently published in the prestigious Chinese Journal of Aeronautics. The research proposes a novel Dynamic Thermal coupling Model (DTM) method, shedding light on the multi-physics thermal interactions and their dynamic impact on system performance.

The paper was co-authored by Fan Siming, Wang Shaoping, Wang Qiyang, Wang Xingjian, Liu Di, and Wu Xiao, with Professor Wang Shaoping as the team leader and Professor Wang Xingjian as the corresponding author.

With the rapid development of modern aircraft, the Electro–Hydrostatic Actuator (EHA) is utilized in more electric aircraft to improve reliability, safety, and maintainability of the flight control system. In EHA, the Oil-Immersed Motor Pump (OMP) serves as the core as a power assembly. However, the compact integration of the OMP presents challenges in efficiently dissipating internal heat, leading to performance degradation of the EHA due to elevated temperatures. Therefore, accurately modeling and predicting the internal thermal dynamics of the OMP hold considerable significance for monitoring the operational condition of the EHA.

To address these challenges, Professor Wang’s team proposed a thermal modeling approach that considers the cumulative effects of thermal coupling. Based on this method, a dynamic thermal model that considers the effects of heat transfer and accumulation on the temperature distribution within the OMP system was developed. The model includes heat accumulation models for the OMP system and heat transfer models for oil leakage into the motor. Experimental verification and simulation comparison results have shown that the model can accurately forecast the temperature distribution and trend within the system under various operating conditions.

Internal heat generation and transfer relationship of OMP

This study provides a new methodology for thermal modeling and performance prediction of oil-immersed EHA systems, with promising applications in high-reliability equipment across aviation, aerospace, and marine industries. The findings hold significant engineering value for improving system safety and extending operational lifespan.

Link to the paper: https://www.sciencedirect.com/science/article/pii/S1000936124003935?via%3Dihub

Editor: Lyu Xingyun