NASA SBIR 00-II Solicitation


PROPOSAL NUMBER: 20.01-9569 (For NASA Use Only - Chron: 000432 )
PROPOSAL TITLE: High Heat Flux Electronics Cooling Cycle

The increased capabilities and decreasing size of satellites will continue to push the requirements of onboard thermal control systems. The capillary pressure limit for current passive thermal systems such as heat pipes and Capillary Pumped Loops (CPL) serves as a barrier beyond which such systems cannot be effectively employed.

In Phase I, TDA Research, Inc. (TDA) demonstrated a passive heat transport system that generates large driving pressures to circulate the working fluid. An analytical model of the system performance was developed and a large data set that validates the model was collected. A loop employing poor-performing R-134a was demonstrated to outperform a CPL employing high-performing ammonia. The high-pressure delivery of the loop allows greater heat rejection over significantly longer distances and against gravity. Experiment-limited transport up to 2330W, at 42W/cm2, over a 16m distance was demonstrated. Driving pressure differences over 1.8Mpa (262psid) were achieved. The performance of this passive loop may be best compared with mechanically pumped cycles.

In Phase II we will demonstrate turnkey operation of the loop for high power, high heat flux, long transport distance applications. We will also map the operational window of the loop and supply the analytic design tools necessary to build systems to meet customer needs.

The passive thermal transport loop generates high driving pressure gradients: it competes with mechanically pumped cycles but does not require a pump. It does not suffer from capillary flow or pool boiling limitations. Aerospace commercial applications will be in the thermal control of unmanned satellites (i.e., communication satellites) for the removal of heat from electronic components. Terrestrial applications include high-volume commercial electronics cooling and residential heating applications.

NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR (Name, Organization Name, Mail Address, City/State/Zip)
Dr. Mark M. Weislogel
TDA Research, Inc.
12345 W. 52nd Ave.
Wheat Ridge , CO   80033 - 1917

NAME AND ADDRESS OF OFFEROR (Firm Name, Mail Address, City/State/Zip)
TDA Research, Inc.
12345 W. 52nd Ave.
Wheat Ridge , CO   80033 - 1917

Form Printed on 11-26-01 17:18