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Visualization of the freeze/thaw characteristics of a copper/water heat pipe - Effects of non-condensible gasThe freeze/thaw characteristics of a copper/water heat pipe of rectangular cross section were investigated experimentally to determine the effect of variations in the amount of non-condensible gases (NCG) present. The transient internal temperature profiles in both the liquid and vapor channels are presented along with contours of the frozen fluid configuration obtained through visual observation. Several interesting phenomena were observed including total blockage of the vapor channel by a solid plug, evaporator dryout during restart, and freezing blowby. In addition, the restart characteristics are shown to be strongly dependent upon the shutdown procedure used prior to freezing, indicating that accurate prediction of the startup or restart characteristics requires a complete thermal history. Finally, the experimental results indicate that the freeze/thaw characteristics of room temperature heat pipes may be significantly different from those occurring in higher temperature, liquid metal heat pipes due to differences in the vapor pressures in the frozen condition.
Document ID
19910058841
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Ochterbeck, J. M.
(Texas A&M Univ. College Station, TX, United States)
Peterson, G. P.
(Texas A & M University College Station, United States)
Date Acquired
August 15, 2013
Publication Date
June 1, 1991
Subject Category
Fluid Mechanics And Heat Transfer
Report/Patent Number
AIAA PAPER 91-1402
Accession Number
91A43464
Distribution Limits
Public
Copyright
Other

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