CubeSat Thermal Control

Increases in power density mean that better thermal control measures are needed for CubeSats. ISISPACE and NLR have identified this need for solutions and have developed solutions for CubeSat thermal control. A mechanically pumped loop developed by Royal NLR provides a reliable solution for dissipating the heat produced by the satellite’s electronics. NLR developed a modular modelling application in the space thermal analysis tool ESATAN-TMS that demonstrates how this mini pump can be an effective solution.

Mechanically pumped Loop

To integrate a TCS into a CubeSat, it needs to be low-cost, physically small, low in power consumption and both modular and flexible. As a robust solution for this, Royal NLR developed a new thermal concept, the mini mechanically pumped loop (MPL). The MPL transports the heat dissipated at one, or multiple hot spots to thermal radiators where the heat is radiated away into space. The heart of the system is the multi-parallel micro-pump (MPMP), which provides a low-mass MPL solution with high reliability due to having multiple pumps operating in parallel to generate the flow. This design avoids the single point of failure of one pump in the loop. The individual micro-pumps are piezo-driven displacement pumps with passive micro-valves. The flat design allows similar performance both on the ground and in micro-g operations in space. The mini MPL is designed to be capable of a heat transport of at least 20 W which can be increased as desired up to 200 W. This heat transport is achieved by using less than 5% of the transported heat equivalent as input power. The total mass of the system is less than 700 gram and its volume is about 0.5 U.

CubeSat modular thermal modeling

The absence of thermal control solutions for current CubeSats is inherently related to their short development times, which have resulted in suboptimal thermal designs. Increases in power density mean that thermal control measures are needed, requiring low-cost hardware and software solutions. Together with ISISPACE, NLR developed an innovative modular approach for CubeSat thermal analyses using ESATAN-TMS. The key to this approach is the interchangeability and scalability of validated thermal submodels allowing fast and more accurate analysis for low Earth orbit (LEO) missions. Any design can be quickly evaluated in ESATAN-TMS in the CubeSat frame model. Eventually, the thermal model can describe the advantages and drawbacks of the system compared to conventional thermal design options.