Helium Buffer Seals are used in Liquid Oxygen (LOX) Pumps to separate hydrogen enriched steam from the cryogenic liquidoxygen. A prime example is the space shuttle main engine LOXpumps. Prior investigations have shown that advanced fluid-filmseals can significantly improve performance and reduce leakage. The savings in helium storage requirements translate to anadditional 1000 pounds of payload that could be carried aboardthe shuttle. The proposed program is intended as a technologydevelopment program for potential application to futurepropulsion systems. Shuttle pump conditions are used for model purposes. Design and analysis of two circumferential sectoredbuffer seals are proposed. The first involves modifications toimprove a T-shaped sector that had been previouslyinvestigated.. The second design employs opposed L- shapedsectors. The program will establish configurations, producepeformance predictions and design drawings.Commercial Applications:These buffered seals can be utilized where ever a particularsystem contains a pressure generating device, such as acompressor, and where system fluids require absolute separation. An example is the prevention of high temperature gas fromentering an oil lubricated bearing compartment and causing oilcoking. Machinery examples include high temperature turbochargers , jet engines, gas turbines, gas generators andcentrifugal compressors.Note: no official Abstract listing exists of selected NASA Phase II SBIR projects for this year. Hence, this abstract is modified by idi from relevant Phase I data. The specific Phase II work statement and objectives may differ.
