PRELIMINARY G189A COMPUTER PROGRAM MODELING OF THE SPACE STATION ECLSS

The initial development and subsequent evolution of the Environmental Control and Life Support System (ECLSS) for the manned Space Station requires a numerical modeling computer program that can accurately simulate the ECLSS.

The G189 program has successfully provided this modeling function for the Skylab refrigeration system and for the Environmental Control System (ECS) in the Space Shuttle Orbiter. Presently being developed at Boeing Aerospace is an overall Space Station ECLSS model, which is being constructed and operated at increasing levels of complexity.

This paper presents and discusses the Boeing G189A model of the baseline Space Station ECLSS. The model is in an early stage of refinement and includes all ECLSS functional operations except Fire Detection and Suppression (FDS) (which is in the detection mode only during normal Station operation) and the Avionics Air Cooling/Heating portion of the Temperature and Humidity Control (THC) Subsystem. At the present level of development, the model is used primarily to obtain detailed fluid-interface mass flows and other mass-balance information, while thermal exchange and interrelationships are very simplified.