NASA SBIR 2008 Solicitation


PROPOSAL NUMBER: 08-1 X8.01-9307
SUBTOPIC TITLE: Detachable, Human-Rated, Ablative Environmentally Compliant TPS
PROPOSAL TITLE: Heatshield Ablation Pattern Roughness Onset and Effects

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
St. Croix Research
5535 Fern Dr.
San Jose, CA 95124 - 6311
(408) 723-1216

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Charles Powars
5535 Fern Dr.
San Jose, CA 95124 - 6311
(408) 723-1216

Expected Technology Readiness Level (TRL) upon completion of contract: 4

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
This project will develop a practical method for predicting pattern roughness onset and quantitative effects on heat and mass transfer rates for heatshield materials such as Phenolic Impregnated Carbon Ablator (PICA) and environments such as those anticipated for the Crew Exploration Vehicle (CEV). Surface roughness patterns (e.g., scallops, crosshatching) form on many materials ablating under turbulent flow conditions. Equivalent sand grain roughness models are inaccurate and inappropriate for calculating Stanton numbers. In Phase I, we will develop a near-term method based on pattern roughness data, observations, and models from diverse fields. This method may predict Stanton number increases directly from material and aerothermal environment information instead of sequentially predicting pattern dimensions, equivalent roughness height, and Stanton number effects. We will also plan a more rigorous longer-term model and validation tests to be implemented in Phase II.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The ablative material pattern roughness onset and effects prediction method we propose to develop is directly applicable to the PICA heatshield material tentatively planned for the Orion CEV. Unlike most previous earth and planet entry missions, turbulent flow conditions are anticipated for CEV. Although PICA-CEV pattern roughness development and effects are unknown, other materials ablating in turbulent flow conditions usually develop surface roughness patterns, and factor-of-two increases of heat transfer and ablation rates are not unusual. Current NASA aerothermal environment and heatshield ablation prediction tools do not account for pattern roughness development or effects on heat transfer and ablation. Our proposed technology will also be applicable to other future NASA exploration missions where heatshields are exposed to turbulent fluid flow.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
If our proposed project is successful, it may facilitate an understanding of how to tailor charring ablator material formulations or processing to control turbulent flow induced surface roughness pattern development and effects. This would provide opportunities to partner with material manufacturers and/or patent and license technology. Our predictive model, and possibly our control technology, may also be applicable in other fields where pattern roughness development and effects are issues. Examples include corrosion, ice accretion, dissolution, saltation, and geological erosion.

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.

Launch and Flight Vehicle
Thermal Insulating Materials

Form Generated on 11-24-08 11:56