Effect of Size on Thermal Performance of Limited Size Multilayer Insulation

Abstract

Multilayer insulation blankets are used in various sizes for thermal control of space systems. These multilayer insulation blankets are processed, usually by being seamed and patched. It is qualitatively understood that the thermal performance of small size multilayer insulation is more or less deteriorated. The effects of size of space use multilayer insulation blankets on thermal performance are known qualitatively, but not quantitatively. In this study, the thermal performance of limited size multilayer insulation blankets was measured by using the boil-off calorimeter method with liquid nitrogen. The temperature distribution on a rectangular multilayer insulation was also measured in order to investigate the nonuniformity of the local heat flux across the rectangular multilayer insulation. Thermal performance declines with the decrease of multilayer insulation area. This is because the local heat flux drastically increases in the hem region and the gap between the edge of blanket and base plate. Based on these measurement results, an equation to predict the thermal performance of multilayer insulation blankets of limited size was proposed.