Managing high thermal loads in small satellites - Analysis, design, and verification of a 3D-printed radiator

The increasing focus on small satellite missions currently propels space access and will likely serve as a main driver in the ongoing space revolution. With increasingly complex and energy-demanding payloads, thermal analysis becomes an important cornerstone of mission design even for small satellites. However, currently available modelling solutions cannot easily adapt to the limited development times and resources of such missions. Here, we present a time-resolved, fast, and flexible thermal modelling approach specifically designed to fulfil the requirements for the modelling of small spacecraft. Making use of the increased surface to volume ratio of the satellite geometry, it employs a lumped capacitance network approach in conjunction with a highly parallelized software solution to compute component's individual thermal loads over the whole mission time. Specifically, we identify a critical thermal load within our German 12U nanosatellite. For the required thermal balancing, we employ the feedback from the thermal model to design a radiator with 3D structured surface and bionic heat-conduction geometry by an interdisciplinary topology optimization approach. The incorporation of the resulting radiator geometry successfully mitigates the critical thermal load and displays the strength of the combined approach