DESCRIPTION AND ORBIT DATA OF VARIABLE-CONDUCTANCE HEAT-PIPE SYSTEM FOR THE COMMUNICATIONS TECHNOLOGY SATELLITE

摘要

A variable-conductance heat-pipe system (VCHPS) with methanol as the working fluid and a nitrogen and helium mixture as the control gas was used for the thermal control of a 200-W rf traveling-wave tube of the Communication Technology Satellite. Three stainless-steel heat pipes (one redundant) and an aluminum radiator were designed to transfer 196 watts for an evaporator temperature of 50° C. The system has operated for 3 years with no noticeable change in performance. On four occasions the heat pipes apparently deprived. A short time after reducing the tube power, the heat pipes reprised and the system continued to operate normally. A description, qualification testing, and orbit data of the VCHPS are presented.