NASA SBIR 2007 Solicitation


PROPOSAL NUMBER: 07-1 X11.01-8478
SUBTOPIC TITLE: Thermal Control for Surface Systems and Spacecraft
PROPOSAL TITLE: VCHP Radiators for Lunar and Martian Environments

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

Expected Technology Readiness Level (TRL) upon completion of contract: 3 to 4

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
Long-term Lunar and Martian systems present challenges to thermal control systems, including changes in thermal load, and large changes in the thermal environment between Lunar (or Martian) day and night. The Lunar thermal environment typically includes long periods in extremely cold thermal environments. A variable conductance heat pipe (VCHP) radiator will be developed that passively accommodates the changing thermal load and environment. In a VCHP, a non-condensable gas is added that blocks a portion of the condenser. The gas charge blocks more of the condenser as the heat pipe evaporator temperature changes. This allows the heat pipe evaporators (and any attached heat exchanger) to remain at an almost constant temperature. In addition to passively controlling the thermal load, the gas allows the fluid in the heat pipe to freeze in a controlled fashion as the heat pipe is shut down, avoiding damage. In addition, the gas in the VCHP will help with start-up from a frozen condition.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The immediate NASA application is for Lunar and Martian radiators that can passively accommodate the large swings in environmental conditions between Lunar (or Martian) day and night, including long periods at very low temperatures. In addition, the VCHP can passively accommodate large changes in thermal load, and avoid damage during periods of low thermal load. In addition, the non-condensable gas in the VCHP will help with the heat pipe start-up from cold conditions.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
A commercial application is VCHP heat exchangers 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 reactant flow rate. The current scheme uses a bypass valve, which has several drawbacks: it requires active control, requires power, and has a large pressure drop. ACT believes that VCHP heat exchangers can replace the current heat exchanger and control system with a passive system that automatically maintains the output stream from the heat exchanger at a constant temperature.

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.


Form Generated on 09-18-07 17:50