Convection Cooling of Power Electronics Operating in Deep-Space

Since most traditional spacecraft are designed to operate in a vacuum environment, forced convection cooling has seen limited use in space-applications. This paper considers an ideal candidate–the Dragonfly Lander, a rotorcraft being sent into Deep-space to conduct experiments on Saturn's largest moon, Titan. A forced convection based thermal management solution is presented for the Rotor Drive Electronics (RDE) unit, a high-power electronics box responsible for controlling the rotors that allow the Lander to fly on Titan. A thermal flow model was built in Solidworks Flow Simulation to evaluate the effectiveness of a fan system integrated into the packaging design and used as the primary method for cooling the RDE. The model was validated with temperature data collected from custom designed ground support equipment. It was found that utilizing forced convection allows temperatures of the electronics within the tightly packaged RDE to remain within operational limits when conductive and radiative heat transfer alone are insufficient. Titan's dense atmosphere results in greater mass flow rates through fans compared to on Earth, making forced convection a particularly efficient method of heat transfer. This research may guide the use of forced convection in future space missions, or non-traditional environments.