Future space exploration missions require advanced thermal control systems (TCS) to dissipate heat from spacecraft, rovers, or habitats to external environments. These TCSs must be lightweight, reliable, and able to effectively control cabin and equipment temperatures under widely varying heat loads and ambient temperatures. In contrast to single‑phase pumped coolant loops, two‑phase pumped loops are very attractive for this application because of the uniform cooling temperature provided by the boiling coolant, low required pumping power, high‑heat transfer coefficients, and high thermal conductance. However, introduction of two‑phase flow can pose design challenges associated with flow management and dynamic stability. A condensing radiator technology is needed to enable future heat rejection systems with high turndown ratio, compatibility with freezing, and deployability, while balancing considerations unique to two‑phase flow condensation. To meet these performance requirements, Creare has developed a freeze‑tolerant, variable‑conductance radiator for deployable heat rejection in two‑phase pumped loop systems.
Creare’s freeze‑tolerant radiator is designed specifically with NASA’s needs in mind, in particular to enable deployable heat rejection from space‑borne two‑phase pumped loop systems. The technology would be applied to dissipate heat from spacecraft, rovers, or habitats to external environments. In addition to thermal control, this system could be used for heat rejection in a Rankine power cycle.
An active industry is developing around use of two‑phase TCSs for satellite thermal management. Several large satellite manufacturers and integrators are working to develop and implement space‑borne two‑phase thermal control loops for powerful telecommunications satellites seeking to reject 1‑10 kW. These systems would require a condensing radiator similar to Creare’s proposed technology.