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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Polymeric materials in expulsion bladders for cryogenic liquids, describing fabrication, flexibility, permeability, storage, transfer, control factors, etc
The NASA Portable Life Support System (PLSS) for the Exploration Extravehicular Mobility Unit (xEMU) incorporates a Feedwater Supply Assembly (FSA) to store consumable cooling water. The FSA accepts pure water prior to each Extra-Vehicular Activity (EVA), then supplies this water to a membrane evaporator at ambient suit pressure during the eight hour EVA. The FSA must function reliably for hundreds of EVAs over 15 years of service without introducing contamination that may accumulate and foul the membrane. We present a unique design that combines the benefits of a flexible fluoropolymer bladder with the strength and convenience of a rigid tank, providing an ultra-pure, ambient-pressure reservoir with fill-drain cycle life exceeding 3000, internal pressure tolerance exceeding 100 psi, high volumetric efficiency, near-zero dead volume, optical transparency for visual inspection, simplified mounting, and very low mass. We also incorporate a novel volume sensor suitable for both microgravity and arbitrarily accelerated environments and capable of real-time monitoring with accuracy on the order of 2.5% full scale. Analytical predictions are supported by experimental test data from a mature subscale prototype.
Calibration of a pressure switch is accurately checked by a thin-walled circular bladder. It is placed in the pressure switch and applies force to the switch diaphragm when expanded by an external pressure source. The disturbance to the normal operation of the switch is minimal.
Polymeric cryogenic positive expulsion bladders filled with liquid hydrogen
Gold braze investigation of multicycle metallic reversing bladders
Chemical compositions, propellant permeability, and mechanical properties of storable propellant bladder materials based on polymeric chemical structure
Polymer positive expulsion bladders for liquid oxygen systems
Polymeric materials in expulsion bladders for cryogenic liquids, describing fabrication, flexibility, permeability, storage, transfer, control factors, etc
Permeation reduction of nitrogen oxides in teflon expulsion bladders through chemical vapor deposited aluminum coatings
Teflon bladders to ensure positive expulsion of fuel and oxidizer for Surveyor Vernier Propulsion System
Steady state leakage rate by diffusion through laminated composite bladder structure with cylindrical hole
Inflatable bladder facilitates the removal of heavy, highly finished metal parts from tote boxes or shipping containers. The proposed concept permits removal without danger of damage to the parts or injury to handling personnel.
Leak-free clamping of a two section accumulator is accomplished by a flat metallic ring molded peripherally to the rubber flange of the bladder, and an inset rubber seal bonded to the face of the flange of each section. Method maintains constant torque on the clamping bolts.
Multiply polymeric films tested for use as liquid hydrogen positive expulsion bladders
Chemical vapor deposition of aluminum permeation barriers in Teflon-aluminum laminated expulsion bladders
Aluminum foil-Teflon laminates for positive explusion bladder materials
Technique development and test methods for improvement of polytetrafluoroethylene films for bladder expulsion
Expulsion bladders for metering propellants into rocket engine thrust chamber and for testing rubber-to-gold adhesive system