Hydraulic Design of the Space Station Active Thermal Control System Utilizing SINDA/FLUINT Flow Models

An analysis method has been developed to aid in the design of the ammonia thermal control system of the Space Station. Although developed for a specific thermal control system, the method is applicable to other systems with a similar working principle. The method uses SINDA/FLUINT models with basic concepts in engineering and statistics and comprises the logical approach to organizing a large number of pertinent parameters to obtain an optimum yet robust design and to evaluate the degradation of system performance caused by variations in the pertinent parameters. The analysis is described in the iterative design/analysis of the thermal control system and consists of the sizing of the ammonia lines, flow control orifices, the best-estimate model, and the departure from the best estimate of flow distribution due to the uncertainty bands of the system components.