Project Title:

Passive, Modular, Heat-Driven Heat Pump for Lunar and Martian Explorations

92-1-09.10-6551A                                                  NAS09-18928
Passive, Modular, Heat-Driven Heat Pump for Lunar
     and Martian Explorations
Thermacore, Inc.
780 Eden Road
Lancaster, PA  17601
Nelson J. Gernert                                    (717-569-6551)

Abstract:

     A self-contained, modular, passive, low-to-medium
temperature, heat-driven, heat pump refrigerator will be developed
for cooling components in a Lunar or Mars environment. The heat
pump uses a gravity-assisted capillary pump loop, heat pipes, and
"steam jet" ejector principles requiring no moving parts. Phase I
will test the principle of the heat pump system. A non-optimized,
scaled, proof-of-concept, heat-pipe heat pump will be tested to
demonstrate the concept's feasibility. Estimates of performance
show a 50øC lift, from 10øC to 60øC, is possible using lunar
gravity and existing wick technology. A lift of 70øC could be
achieved if existing wick pore radii can be reduced in size by a
factor of 2. This passive, heat-driven, heat pump is effective,
and using a capillary pump and "steam jet" ejector principles
provides a reliable, compact system that is easy to operate and
maintain. This heat pump concept provides a mechanism for
rejecting heat during the lunar day. Improvements in wick pumping
capability can also lead to overall reductions in main radiator
sizes.

Potential Commercial Application:

Potential Commercial Applications:  A number of industries, such
as steel, refineries, chemical, marine, and electrical utilities
projects have waste heat that could be used to power air
conditioning. This project's passive design may prove cost-
effective for these applications, but an automobile air
conditioning system powered from engine heat seems to be the most
attractive commercial opportunity.

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