The Stability of In-Space Cryogenic Systems experiment will study the stability of spacecraft propellant during refueling as it relates to temperature and mechanical disturbances,which are important measurements for preventing flow control failure and equipment damage. Testing on parabolic flights will assess the threshold of heat pulses and vibration at which flow oscillations are triggered. Tests will also evaluate the factors controlling liquid nitrogen flow stability and, if successful, result in a strategy to enhance propellant stability and prevent hydraulic shocks.

Problem Statement
The storage and transfer of cryogenic propellants in microgravity is critical for lunar and deep space exploration. Thermal-hydrodynamic instabilities on long-duration missions could make controlling propellant and the propellant transfer process more difficult. More research is needed to determine safety parameters for propellant refueling with heat and mechanical disturbances.

Technology Maturation
Knowledge gained from parabolic flight tests will advance technology for cryogenic transport operations in space–to which NASA has currently assigned a TRL of 4 –to TRL 6. This demonstration will assess the role of gravity in propellant transport by measuring the contrast in heat and mechanical disturbances between a ground and microgravity environment, supporting the development of propellant stability guidelines.

This knowledge payload could advance the field of cryogenic storage and transfer overall. In addressing this critical NASA need, this technology will establish guidelines for and reduce the risk of in-space propellant transfer by analyzing the role of gravity in potential propellant disturbances. These guidelines are crucial for sustainable, long-duration space missions as well as ground-based cryogenic management. This would benefit NASA missions and the commercial space industry.

Future Customers
•Long-duration space exploration missions
•Ground-based cryogenic applications