Wing-Integrated Surface Heat Exchanger for Electric Propulsion Units in Regional Aircraft

The present study addresses the cooling of electric components for a regional aircraft architecture that features fuel cell electric propulsion with eight electric propulsion units distributed along the wings, while the fuel cell system is located separately from these units. This enables the use of the wing surface for heat dissipation while increasing heat transfer by exploiting the propeller slipstream. The results show that the waste heat produced by the electric propulsion units in the considered megawatt power class can be dissipated to the ambient airflow, leaving enough margin to even cover critical off-design operating points such as hot and high take-off scenarios. Further, sensitivity studies show that with varying geometries and geometrical boundary conditions the electric components can be cooled sufficiently. Thus, the wing-integrated surface heat exchanger represents a stand-alone cooling concept for the relevant electric components in the investigated aircraft architecture by decreasing the relative fuel burn penalty by 6% compared to the reference ram air heat exchanger configuration.