Aerodynamic shape optimization of an electric aircraft motor surface heat exchanger with conjugate heat transfer constraint

Electrified aircraft benefit from the versatile ways electric motors can be integrated with an airframe. However, thermal management is needed to move waste heat out of the motors because the heat is not expelled with the exhaust as in a conventional engine. Plate-fin, fin, and surface heat exchangers are incorporated as air-side heat exchangers for electrified aircraft thermal management systems. Typically, analytic tools are used to design heat exchangers within these categories. However, analytic tools lack the fidelity required for detailed shaping and assessment of general heat exchanger configurations. Tools based on first principles, such as finite element analysis or computational fluid dynamics, can verify heat exchanger performance but are too costly to use in a manual design loop. Shape optimization can be used with first-principles-based models to design heat exchangers without limiting the geometry to those previously well studied. In this work, we apply this methodology to design a heat sink for the high-lift motor of an electric technology demonstrator, the X-57 Maxwell. We use a gradient-based optimizer to modify the