NASA STTR 2008 Solicitation


PROPOSAL NUMBER: 08-2 T7.01-9911
RESEARCH SUBTOPIC TITLE: Predictive Numerical Simulation of Rocket Exhaust Interactions with Soil
PROPOSAL TITLE: High-Fidelity Gas and Granular Flow Physics Models for Rocket Exhaust Interaction with Lunar Soil

NAME: CFD Research Corp. NAME: University of Florida
STREET: 215 Wynn Drive, 5th Floor STREET: P.O. Box 116550 (339) Weil Hall
CITY: Huntsville CITY: Gainesville
STATE/ZIP: AL  35805 - 1944 STATE/ZIP: FL  32611 - 6550
PHONE: (256) 726-4858 PHONE: (352) 392-9448

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Peter Liever
215 Wynn Drive
Huntsville, AL 35805 - 1944
(256) 726-4800

Estimated Technology Readiness Level (TRL) at beginning and end of contract:
Begin: 5
End: 6

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
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.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The debris simulation tool will be of first order importance to the Space Exploration program for lunar robotic and human mission architecture definition. The tool will be equally applicable to follow-on Mars robotic and human missions. The developed technology will also be applicable for analysis of solid propulsion systems with embedded solid particle.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
Many potential non-NASA commercial applications exist in civil and military industries. Dust, sand and snow stir-up during helicopter landing and take-off in a desert or arctic environment result in severe visibility impairment (brown-out), windshield abrasion and danger of debris ingestion. Civil engineering and environmental engineering applications include wind-borne landscape erosion and dust transport to populated areas

TECHNOLOGY TAXONOMY MAPPING (NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.)
Fundamental Propulsion Physics
Simulation Modeling Environment
Software Tools for Distributed Analysis and Simulation
Testing Requirements and Architectures

Form Generated on 05-25-10 13:36