High Conductivity Carbon-Carbon Heat Pipes for Light Weight Space Power System Radiators

Based on prior successful fabrication and demonstration testing of a carbon-carbon heat pipe radiator element with integral fins this paper examines the hypothetical extension of the technology via substitution of high thermal conductivity composites which would permit increasing fin length while still maintaining high fin effectiveness. As a result the specific radiator mass could approach an ultimate asymptotic minimum value near 1.0 kg/m 2 , which is less than one fourth the value of present day satellite radiators. The implied mass savings would be even greater for high capacity space and planetary surface power systems, which may require radiator areas ranging from hundreds to thousands of square meters, depending on system power level. Nomenclature A i inner surface area; A o outer surface area A r ( j ) incremental radiator area at section j dA i elemental inner wall surface, or heat pipe evaporator area dA r dA o , is the elemental radiating outer wall surface, or heat pipe condenser area