Helium Refueling Demonstration for On-Orbit Servicing Applications using Efficient High-Pressure-Ratio Compressor

Flight Works Inc. proposes to develop an efficient helium compressor for on-orbit servicing applications and to demonstrate key elements of the concept under Phase I with hardware tests. As noted in the topic description, the current state of the art for efficient and timely on-orbit transfer of gaseous fluids, specifically helium, in large quantities is nonexistent. Flight Works has been developing such capability for Xenon up to 3000 psi and will adapt that concept to the higher pressures needed for efficient helium transfer. The approach uses a multi-stage compression scheme with inter-stage cooling to optimize the work done on the fluid and reduce waste heat. This scheme allows for a large pressure-ratio of both high outlet pressures (6000 psia) and low inlet pressure (500 psia) to maximize the applicability of this servicing technology. The Phase I R&D technical objectives focus on obtaining high pressure test data with helium to guide the design of the high-pressure helium compressor. This is done by leveraging the Xenon compressor design and using that compressor as a point of departure for helium. This leads to a preliminary design of the flight unit capable of compressing helium from 500 psia to 6,000 psia with less than 600 W. It also includes the development of a (near) detailed design of a flight engineering development unit to be finalized, built and tested under Phase II. The proposed innovation is an efficient helium compressor for on-orbit servicing application. The current state of the art for efficient and timely on-orbit transfer of gaseous fluids, specifically helium, in large quantities is nonexistent. Flight Works has been developing such capability for Xenon up to 3000 psi and will adapt that concept to the higher pressures needed for efficient helium transfer. The approach uses a three-stage compression scheme with inter-stage cooling to optimize the work done on the fluid and reduce waste heat. This scheme allows for a large pressure-ratio of both high outlet pressures (6000 psia) and low inlet pressure (500 psia) to maximize the applicability of this servicing technology. While developed for helium, the compressor can be used for a wide range of other gases such as argon, krypton, methane and nitrogen. It can also be modified to operate with oxygen.
Benefits: The compressor is designed for on-orbit transfers of helium and can be used to service any spacecraft using helium or other gases such as krypton, nitrogen, methane, etc. Because it is highly scalable and designed to move inert gases, refrigeration and thermal management tasks are likely candidates. It can also be modified to be compatible with other gases such as oxygen. Overall applications include electronics or optics cooling, and recompression systems. Scavenging gases for processing in habitats (space stations, lunar bases) or sampling missions, or even deflating structures for relocation or re-entry, are other potential applications. Non-NASA applications include helium (and other gases such as nitrogen or krypton) on-orbit refueling of DoD and commercial spacecraft. For example, refueling of spacecraft chemical propulsion systems that include refilling of a high-pressure helium storage. The scalability and versatility of the system in compressing gases makes it an attractive candidate for numerous fluid systems.