Phase Change Materials (PCMs) are substances with the capacity to absorb and release significant amounts of latent heat during phase transitions, making them invaluable for thermal management in space applications. They are usually stored in a container, usually called PCM heat capacitor, which is hermetically sealed and thermally coupled to a dissipative unit. The most common and efficient PCMs are the paraffins, which include many compounds offering different transition temperatures. PCM capacitors have been used for a long time on several Space missions, and are still being developed and improved. Although they have used on several launchers, entry or re-entry vehicles, it is not common to find them on European orbiting missions, with long-term utilization including many thermal cycles. In this paper, we will explore the potential applications of PCMs in thermal regulation within orbiting spacecrafts, efficiently absorbing excess heat during peak of dissipation or exposure to sunlight and releasing it during periods of idle or shadow. Parametric studies presented in this paper show that a PCM capacitor coupled to a highly dissipative unit with a low duty cycle can help saving a significant portion of the radiator area and thus heating power when off, without mass penalty. These analyses have been supported by several tests to both extend the qualification of PCM capacitor to long-term missions, including thermal cycling, mechanical tests, burst tests and radiation, and to characterize their thermal performances. These latter tests have enabled the development of a consolidated correlated thermal mathematical model, which parameters will be explained in the paper. This paper eventually highlights the significance of PCMs in enhancing thermal control for specific cases, in particular when power consumption saving is crucial.
Peyrou-Lauga et al. (Sun,) studied this question.