Description:

The need and demand for long term space missions, such as missions to Near Earth Object’s (NEO’s) and interplanetary missions, is growing rapidly. To satisfy this demand, on-orbit propellant storage and transfer technologies are being developed. The ability to re-fuel a space system, once on-orbit, will provide a means of success for these types of space missions without the need for continual development and advancement of heavy lift vehicles. Additionally, the adaptation of existing technology will allow on-orbit refueling of spacecraft to become a near term reality, cutting the need for advanced heavy launch vehicle development as well as the corresponding cost, time, and manpower.

This effort was awarded an SBIR Phase I in 2019: Spacecraft On-orbit Advanced Refueling and Storage.

Problem Statement 
Currently, the United Launch Alliance (ULA) is developing on-orbit propellant storage and transfer systems that are derived from the Centaur upper stage of the Atlas launch vehicle. Once on-orbit, these systems will be spin stabilized about their major axis while several propellant transfers take place. During these propellant transfers flowing liquid propellant, pressure gradients, and liquid slosh caused by the oscillatory motion of the space system are anticipated to pose a drastic change on the system’s rotational dynamics. To further advance propellant storage and transfer technologies, the dynamics of on-orbit propellant transfers need to be understood.

Technology Maturation 
A successful completion of the proposed microgravity testing will advance the current knowledge of these space systems and raise the Technology Readiness Level (TRL) of cryogenic propellant transfer systems from 4 to TRL 6.


Overview of Flight Test
The Eigen Systems’ SOARS payload flew aboard Blue Origin NS-35, successfully demonstrating autonomous multiphase fluid management and advancing the Gravitational Flow Reactor (GFR) to TRL-7. Building on NASA’s Flight Opportunities maturation pathway, GFR is now positioned for follow-on demonstrations that could align with STMD priorities in Cryogenic Fluid Management and the Lunar Surface Innovation Initiative, while potential applications in biomanufacturing and in-space production applications (InSPA) and future Commercial LEO Destinations (CLD). In the longer term, GFR may also support ESDMD exploration architectures for Artemis, with broad translation opportunities across in-space refueling, ISRU, biomanufacturing, and life support systems.
 

Benefits: This technology is intended to benefit future NASA missions such as those to Near Earth Objects (NEOs) and other planets by supporting the ability to re-fuel an on-orbit space system. This ability will potentially limit the need for continual development and advancement of heavy-lift vehicles that must carry all of the required fuel for the duration of the mission at launch.