Advanced Two-phase Thermal Management In Spacecraft

Abstract

Advanced thermal control systems have been considered for spacecraft applications in the areas of heat acquisition, heat transport and heat rejection. A desirable system minimizes the temperature drop between the payload and the radiator to reduce the area and weight of the radiator. The heat pipe radiator/heat exchanger must be compact and lightweight. The heat exohanger musk be able to accommodate either mechanically pumped or capillary pumped two-phlase loops without serious operational constraints. A simple analysis shows that the amount of savings of the radiator area is a function of the heat flux applied to the payload. Nomenclature h, hi * interface heat transfer coefficient = overall heat transfer coefficient of cold plate, W/cm*-K between payload and cold plate, W/cma-K q" = heat flux, W/cmZ S = saving of radiator area, % To = cold plate condenser temperature ,K Tp = payload temperature, K Tr = radiator temperature, K T r r E = temperature of current radiator, K T,,, = temperature of new radiator, K T* =i sink temperature, K