Expert Systems Applied to Spacecraft Fire Safety Unclad Prepared for Lewis Research Center under Purchase Order C-32000-m
SUMMARY E x p e r t systems a r e p r o b l e m-s o l v i n g programs t h a t combine a knowledge base and a r e a s o n i n g mechanism t o s i m u l a t e a human " e x p e r t. " The development o f an e x p e r t system t o manage f i r e s a f e t y i n s p a c e c r a f t , i n p a r t i c u l a r t h e NASA Space S t a t i o n Freedom, i s d i f f i c u l t b u t c l e a r l y advantageous i n t h e l o n g-t e r m. The r e p o r t d i s c u s s e s some needs i n l o w-g r a v i t y f l a m m a b i l i t y c h a r a c t e r i s t i c s , v e n t i
Safety considerations in the design of manned spaceflight hardware
Some of the significant potential hazards affecting NASA's planned space-flight initiatives are discussed together with the safety design strategies they mandate. Attention is given to the role played by NASA's newly centralized safety organization during the design of manned space flight hardware and software. Prompt-effect/physical hazards include fire, explosions and depressurization, and natural and man-made space debris. Delayed-effect hazards include radiation and toxic contamination, microgravity effects, crew illness and injury, and isolation. Safety design considerations for software and hypersonic transatmospheric vehicles are evaluated.
Suppression of Fires in Confined Spaces by Nitrogen Pressurization: Ml Extinction Limits for Liquid Pool Fires
Abstract Larger scale studies of liquid pool fires involved varying the pool surface area and depth, the chamber size and geometry, the pressurization rate, and the fuel and fuel temperature. Fuel-oxidant mixing and fuel temperature are the primary determinants of how much nitrogen is needed for flame suppression. In the worst cases, turbulent fires of boiling n-heptane or ethanol, reduction of the ambient oxygen concentration to about 10.9 percent by volume was required. The results are discussed with regard to other extinction experiments and are found to be consistent.