Development of a thermal environment simulator for large test articles in a vacuum

The simulation of the thermal environment by varying the effective sink temperature about the test article was examined. The accuracy of this simulation depends upon the spectral emissivity/absorptivity, the number and size of the control zones, the temperature of each zone, and the geometry of the enclosure. A very large number of zones closely conforming to the surface of the test article quickly become prohibitive due to expense and control problems. A two zone low price enclosure does not have the fidelity required for thermal balance testing. The development of a simulator which for a reasonable cost, simulates the thermal balance environment for most large test articles in the future is described.