Determination of Structural Heat Losses for Orbiter ATCS Operational Simulation

The betterment of Space Shuttle Environmental System Consumables Analysis Program (ESCAP) has been in progress by the determination and incorporation of a newly' developed structural heat loss model. Heat exchange apparently exists among components, orbiter structure, and space/sun/earth. This results in a net heat loss from the orbiter to space for most cases. The heat losses have been correlated to flight parameters in attitude and duration, beta-angle, altitude, and power level. This has corrected a long-standing over-estimation of ATCS heat rejection and heat sink inlet temperatures. It also improves performance prediction of radiators and the subsequent supply water management. Therefore, this work is regarded as a major breakthrough that enables the STS community to perform pre-flight and post-flight studies, thermal analysis tasks, and real-time console support with high fidelity for Space Shuttle missions.