Thermal Environment Simulator for Vacuum Testing of Large Spacecraft

A thermal environment simulator (TES) with 56 independently controllable temperature zones has been developed for Martin Marietta's Space Simulation Laboratory. This simulator is designed to test shuttle payloads in a thermal vacuum chamber with liquid nitrogen cold walls. The thermal environment simulator is an alternative to a 4.9-m (16-tt) diameter vertical beam solar simulator and two-axis gimbal system. The simulator can accommodate larger test articles at a lower cost. It provides complex heat flux distributions by surrounding the test articles with a multifaceted temperature environment. Issues resolved during initial operation included vacuum and cryogenic compatibility, control capabilities, instrumentation, calibration, heat flux uniformity, and reliability.