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High-Fidelity Gas and Granular Flow Physics Models for Rocket Exhaust…

Award Information

National Aeronautics and Space Administration
Award ID:
Program Year/Program:
2010 / STTR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
CFD Research Corporation
215 Wynn Dr., 5th Floor Huntsville, AL -
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Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 2
Fiscal Year: 2010
Title: High-Fidelity Gas and Granular Flow Physics Models for Rocket Exhaust Interaction with Lunar Soil
Agency: NASA
Contract: NNX10CB66C
Award Amount: $599,992.00


Current modeling of Lunar and Martian soil erosion and debris transport caused by rocket plume impingement lacks essential physics from the peculiar granular characteristics of highly irregular regolith particles. Current granular mechanics models are based on mono-disperse spherical particles empiricism unsuitable for capturing the poly-disperse irregularly shaped grain mechanics. CFDRC and the University of Florida successfully demonstrated a novel approach in Phase I to develop granular mechanics constitutive models through innovative Discrete Element Methods emulating non-spherical, jagged particles constructed as clusters of linked/overlapping spheres. This first principle modeling captures the fundamental relationship between particle shape and particle-phase stress, cohesion, and particle flow kinetics. In Phase II, detailed regolith granular flow constituent models will be derived with these methods. An Eulerian granular phase model with the resulting constitutive models will be implemented in the Unified Flow Solver (UFS) simulation framework developed by CFDRC and UF for lunar debris transport and applied in Eulerian multi-phase gas-regolith interaction simulations. Surface stresses from turbulent jet plume scouring and regolith roughness that amplify erosion mechanisms will be captured using a Reynolds Stress Turbulence model. The integrated UFS simulation tool will be validated against erosion and cratering experiments with sand, lunar/Mars simulants, and reduced gravity effects. The technology will be applied for Moon/Mars landing crater formation and debris transport predictions. This high-fidelity simulation capability will be essential for predicting regolith dust and debris transport and for developing mitigation measures.

Principal Investigator:

Peter Liever
Principal Investigator

Business Contact:

Silvia Harvey
Business Official
Small Business Information at Submission:

CFD Research Corporation
215 Wynn Drive, 5th Floor Huntsville, AL 35805

EIN/Tax ID: 630944385
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Research Institution Information:
University of Florida
P.O. Box 116550 (339) Weil Hall
Gainesville, FL 32611
Contact Phone: 3523929448