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Variable Conductance Heat Pipes for Radioisotope Stirling Systems

Award Information

National Aeronautics and Space Administration
Award ID:
Program Year/Program:
2007 / SBIR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
Advanced Cooling Technologies
1046 New Holland Ave. Lancaster, PA 17601-5606
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Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 1
Fiscal Year: 2007
Title: Variable Conductance Heat Pipes for Radioisotope Stirling Systems
Agency: NASA
Contract: NNC07QA40P
Award Amount: $69,919.00


The overall program objective is to develop a high temperature variable conductance heat pipe (VCHP) backup radiator, and integrate it into a Stirling radioisotope power system. A VCHP is similar to a heat pipe, but has a reservoir and a controlled amount of non-condensable gas (NCG) inside the reservoir. At low power, most of the condenser is blocked by the NCG. As the power increases, more and more of the condenser becomes active. This allows a VCHP to passively control the temperature while the power varies. Aluminum/ammonia VCHPs are commonly used in spacecraft thermal control. The proposed program will extend this concept to the alkali metal heat pipes that will be required for a Stirling system. During normal operation, the VCHP will be inactive. If the Stirling engine stops working for any reason, the VCHP will passively remove the heat from the General Purpose Heat Source (GPHS) preventing the GPHS from overheating. The benefits of the VCHP radiator include increased safety and reliability, and the ability to design an optimum Stirling engine.

Principal Investigator:

William G. Anderson
Principal Investigator

Business Contact:

Jon L. Zuo
Small Business Information at Submission:

Advanced Cooling Technologies, Inc.
1046 New Holland Avenue Lancaster, PA 17601

EIN/Tax ID: 571146896
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No