Thermal Control Definition of COLUMBUS Pressurized Modules 871483
Thermal Control design of the COLUMBUS pressurized modules is driven by very stringent requirements such as lifetime (10 years for replaceable units and 30 years for non-replaceable units), on orbit reconfigurability of payloads and subsystems, failure tolerance and temperature ranges of equipment and structure.
Thermal design is being defined through a systematic sequence of trade-offs (single versus dual loop concepts, single versus two phase loop, loop arrangements, radiator panel type, optimization of heat load accommodation and regulation…).
A common design concept is established for both the pressurized modules (four and two Spacelab segments in length); water loops are utilized in the manned area of the modules, while freon R114 loops are employed in external areas to collect the heat from the water loop and feed the heat rejection system.
Hybrid radiators (heat pipes panel and fluid header) are employed as they are not drastically damaged by micrometeoroid puncture. The control philosophy and the adaptability of the Thermal Control to any payload configuration represent the most complicated part of the design study and need additional detailed trade-offs.