NASA SBIR 2006 Solicitation


PROPOSAL NUMBER: 06-2 S2.03-8433
SUBTOPIC TITLE: Energy Conversion and Power Electronics for Deep Space Missions
PROPOSAL TITLE: Variable Conductance Heat Pipes for Radioisotope Stirling Systems

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Advanced Cooling Technologies, Inc.
1046 New Holland Avenue
Lancaster, PA 17601 - 5688
(717) 295-6061

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
William G Anderson
1046 New Holland Avenue
Lancaster, PA 17601 - 5688
(717) 295-6104

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
The overall technical objective of the proposed Phase II program is to complete a system-level demonstration to show the capability and benefits of integrating this backup radiator/Variable Conductance Heat Pipe (VCHP) with the Advanced Stirling Radioisotope Generator (ASRG). The Phase I project developed a feasible VCHP radiator design that can be integrated with the ASRG. In Phase II, a trade study will be conducted to optimize the VCHP design. A superalloy heat pipe will be fabricated from Haynes 230, which has good strength at the 850oC operating temperature and long term life tests with alkali metals. In addition to the VCHP, a General Purpose Heat Source (GPHS) simulator and a Heater Head simulator will both be designed and fabricated. Testing of the VCHP with the GPHS and Heater Head simulators will verify the ability of the VCHP to provide backup cooling for the Stirling convertors. The goal at the end of the program would be to bring the concept to Technology Readiness Level 5: Component Validation in a Relevant Environment.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
One potential commercial application based on a current product line at ACT is the pressure-controlled isothermal furnace liner. An isothermal furnace liner is an annular alkali metal heat pipe. Replacing the current heat pipe with a pressure controlled VCHP will allow much tighter temperature control. A second commercial application is the alkali metal VCHPs in fuel cell reformers. In a fuel cell reformer, diesel fuel and air pass through a series of high temperature reactors to generate hydrogen. The operating temperature of the reactors must be closely controlled to maintain their chemical equilibrium. A typical system must maintain inlet and outlet temperatures within ±30oC despite a turndown ratio of 5:1 in the reactant flow rate. The current scheme uses bypass valves, which has several drawbacks: it requires active control, consumes power, and has a large pressure drop. The alkali metal VCHP heat exchangers can replace the current heat exchangers and control valves with a passive system that automatically maintains the output stream from the heat exchanger at a constant temperature.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The immediate NASA application is to provide backup cooling for the Advanced Stirling Radioisotope Generator (ASRG). The heater head lifetime decreases rapidly at temperature above the design temperature of 850oC, so the Stirling engines can only be stopped briefly before the heater head overheats. VCHPs allow the engines to be stopped to minimize electromagnetic interferences and mechanical vibrations while taking scientific measurements for as long as desired, without the danger of damaging the heater head. In addition to allowing multiple stops and starts of the Stirling engines, the VCHPs also help to isothermalize the heater head, increasing the engine performance.

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.

Nuclear Conversion

Form Generated on 08-02-07 14:39