A SUBCRITICAL LIQUID OXYGEN SYSTEM DEVELOPMENT OF A SUBCRITICAL LIQUID OXYGEN SYSTEM

THE PRESENT PRIMARY LIFE SUPPORT SYSTEM (PLSS) UTILIZES HIGHPRESSURE GASEOUS OXYGEN FOR OPERATION, WHICH REPRESENTS A SIGNIFICANT SAFETY RISK AND POTENTIAL LOGISTICS PROBLEMS FORFUTURE MISSIONS. THE USE OF SUBCRITICAL LIQUID OXYGEN FOR PPLSS OFFERS MANY ADVANTAGES, BUT PREVIOUS ATTEMPTS AT USING LOX HAVE NOT SUCCEEDED DUE TO A NUMBER OF PROBLEMS, SUCH AS PRESSURIZATION AND DEALING WITH A TWO-PHASE FLOW IN A MICROGRAVITY ENVIRONMENT. FOSTER-MILLER HAS DEVISED A SUBCRITICAL LOX SYSTEM THAT IS CAPABLE OF ADDRESSING THESE PROBLEMS, WHILE DELIVERING THE BENEFITS OF REDUCED SYSTEM WEIGHT AND VOLUME (28 AND 79 PERCENT, RESPECTIVELY), AND ELIMINATING THE HAZARDS OF HIGH PRESSURE OXYGEN SYSTEMS. THE PROPOSED SYSTEM EMPLOYS A CRYOGENIC TANK EQUIPPED WITH AFLEXIBLE BLADDER, CONSTRUCTED FROM A LIQUID CRYSTAL POLYMER (LCP) MATERIAL, AND A HELIUM GAS SPRING THAT MAINTAINS THE LOX IN A SUBCOOLED STATE, PREVENTING VAPOR FORMATION, MAINTAINING SYSTEM PRESSURE, AND MAKING THE TASKS OF METERING AND INVENTORY MEASUREMENT RELATIVELY EASY.