Volume 68

Lightweight Passive Thermal Management of High-Power Density Electric Aircraft Motors Using Form-Stable PCMs Huanyi Ning1, Xinzhu Mou1,2*, Naseer M. Khan1, Jingyang Zhang1, Weidong Chen3

Abstract

With the rapid development of electric aircraft, thermal management of high power-density motors is increasingly limited by compact structures, high heat flux, and lightweight constraints. This study proposes a passive thermal management strategy for motor housings using form-stable composite phase change materials (FS-PCMs). The FS-PCM exhibits leakage-free phase transition, a melting range of 50–55 °C, latent heat of ~149 J g⁻¹, and good thermal stability. Two identical motor housings, with and without FS-PCM embedded in fin gaps, were fabricated and tested under different heat source temperatures, ambient conditions, and pulsed heating loads. Results show that FS-PCM integration reduces peak temperature by 15–20 °C, delays temperature rise, and induces a stable phase change plateau. Under pulsed heating, the performance strongly depends on the matching between duty cycle, ambient temperature, and phase transition kinetics. Thermal resistance and energy analyses indicate that mechanical compaction reduces interfacial thermal resistance to below 0.1 K W⁻¹, with negligible mass penalty. Overall, the proposed structure provides an effective lightweight passive thermal management solution for aerospace motor applications.

Keywords Latent heat storage; Motor thermal protection; Precision thermal control; Discrete embedding