Analysis of Contamination Degradation of Thermal Control Surfaces on Operational Satellites

The change in performance of a passive radiator, when vent paths are modified to avert contamination flow, is pre­ sented. Solar absorptance increases for the radiator were calculated and compared for three different vent path con­ figurations, on a series of synchronous orbiting satellites. The improved design on the latest flight has drastically reduced the degradation rate. Computer programs have also been developed which model the contamination process using a line-of-sight assumption. This analysis predicted a contaminant distribution that is similar to flight data results. The information can be used to direct the analysis of new satellite designs to minimize the contamination of thermal control surfaces.