- Advance the state-of-the-art for long-term storage of cryogenic fluids in reduced gravity environments by:
- developing the most promising analytical and numerical models;
- anchoring the models with new or existing test data;
- developing the most promising pressure control concepts through a combination of component and system level testing. (TRL ~ 4); and
- gaining experience with full scale loading/control of potential green propellants for future systems.
- NASA Centers involved: Glenn, Ames, Marshall, Goddard
Models of cryogenic space systems require several key features to accurately
predict the tank thermodynamic & fluid behavior.
- Simultaneous time-accurate solution of governing equations in both liquid & gaseous regions
- Heat transfer between gas/liquid/wall/penetrations
- Buoyancy effects
- Variable external heating & acceleration
- Surface tension effects in low gravity
- Multi-species ullage gas with noncondensable component
(and possible diffusion of noncondensable into liquid)
- Interface dynamics & slosh prediction
- Thermodynamic vent systems submodels
- Turbulence modeling
- Effect of LADs
- (if spray bar) Spray atomization, vaporization/condensation, drop interactions
with solid surfaces and liquid/ullage interface
Tank Thermal & Pressure Control Modeling
- Goal is to advance the state of the art in analysis tools (CFD and analytical)
for long term storage of cryogens.
- Model advanced design concepts in the appropriate environment and scale.
- Spray Bar
- Axial Jet
- Zero Boil-Off
- Provide IV&V for the Prime Contractor's design concept under the full range of
mission/environmental conditions (including off-nominal).
- Method will be to develop parallel models (using different codes) and evaluate strengths
and weaknesses of each approach.
- Fluent, CFX, Flow-3D, NCC, CAT, SINDA/FLUINT, GFSSP
- Compare and anchor models to existing ground and flight data.
- Identify additional tests - MHTB, Mass Gauge
Researchers from Combustion Branch:
Jeffrey P. Moder
Anthony C. Iannetti