Project Title:

Cryogenic, Capillary, Pumped Loop

92-1-09.08-0292                                                   NAS05-32415
Cryogenic, Capillary, Pumped Loop
Cullimore & Ring Technologies, Inc.
49 Dawn Heath Circle
Littleton, CO  80127
Brent A. Cullimore                                   (303-971-0292)

Abstract:

     A capillary pumped loop (CPL) will be developed for use in
cryogenic applications such as infrared sensor cooling and long-
term cryogenic storage. CPLs not only overcome some of the
obstacles encountered in missions requiring cryogenic heat pipes,
their important performance improvements extend their use into
applications not currently within the reach of heat pipes.
Important advantages of CPLs over heat pipes include improved
ground testability due to greater capillary pressures; improved
mechanical isolation due to the use of long, thin flexible lines;
faster diode shut down and fewer reverse heat leaks; elimination
of thermal switches in redundant cryocooler applications through
the use of proven condenser flow control techniques; tighter
control of detector temperatures without increasing the rejection
load; and higher performance and greater ease of integration
because CPLs can be assembled from components. Phase I will
experimentally verify the operation of a capillary evaporator pump
using a cryogenic working fluid and will analytically explore
design options that enable start up from a supercritical state.

Potential Commercial Application:

Potential Commercial Applications:  Immediate applications in the
aerospace industry include the production of cold temperatures for
cryogenic sensors and detectors, and the long term storage of
cryogenic liquids for propulsion, environmental control, and
sensor cooling applications. Another emerging application is in
the cooling of cryogenic electronics for the next generation of
computers.

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