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Title: Interfacial thermodynamics of micro heat pipes

Abstract

Successful analysis and modeling of micro heat pipes requires a complete understanding of the vapor-liquid interface. A thermodynamic model of the vapor-liquid interface in micro heat pipes has been formulated that includes axial pressure and temperature differences, changes in local interfacial curvature, Marangoni effects, and the disjoining pressure. Relationships were developed for the interfacial mass flux in an extended meniscus, the heat transfer rate in the intrinsic meniscus, the 'thermocapillary' heat-pipe limitation, as well as the nonevaporating superheated liquid film thickness that exists between adjacent menisci and occurs during liquid dry out in the evaporator. These relationships can be used to define quantitative restrictions and/or requirements necessary for proper operation of micro heat pipes. They also provide fundamental insight into the critical mechanisms required for proper heat pipe operation. 29 refs., 6 figs.

Authors:
 [1];  [2]
  1. (Heat Transfer Research, Inc., College Station, TX (United States))
  2. (Texas A M Univ., College Station, TX (United States))
Publication Date:
OSTI Identifier:
6562640
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States); Journal Volume: 117:1
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; HEAT PIPES; THERMODYNAMICS; INTERFACES; HEAT TRANSFER; THIN FILMS; CAPILLARIES; MATHEMATICAL MODELS; THERMODYNAMIC MODEL; VAPORS; BLOOD VESSELS; BODY; CARDIOVASCULAR SYSTEM; ENERGY TRANSFER; FILMS; FLUIDS; GASES; ORGANS; PARTICLE MODELS; STATISTICAL MODELS; 420200* - Engineering- Facilities, Equipment, & Techniques; 420400 - Engineering- Heat Transfer & Fluid Flow; 990200 - Mathematics & Computers

Citation Formats

Swanson, L.W., and Peterson, G.P.. Interfacial thermodynamics of micro heat pipes. United States: N. p., 1995. Web. doi:10.1115/1.2822303.
Swanson, L.W., & Peterson, G.P.. Interfacial thermodynamics of micro heat pipes. United States. doi:10.1115/1.2822303.
Swanson, L.W., and Peterson, G.P.. 1995. "Interfacial thermodynamics of micro heat pipes". United States. doi:10.1115/1.2822303.
@article{osti_6562640,
title = {Interfacial thermodynamics of micro heat pipes},
author = {Swanson, L.W. and Peterson, G.P.},
abstractNote = {Successful analysis and modeling of micro heat pipes requires a complete understanding of the vapor-liquid interface. A thermodynamic model of the vapor-liquid interface in micro heat pipes has been formulated that includes axial pressure and temperature differences, changes in local interfacial curvature, Marangoni effects, and the disjoining pressure. Relationships were developed for the interfacial mass flux in an extended meniscus, the heat transfer rate in the intrinsic meniscus, the 'thermocapillary' heat-pipe limitation, as well as the nonevaporating superheated liquid film thickness that exists between adjacent menisci and occurs during liquid dry out in the evaporator. These relationships can be used to define quantitative restrictions and/or requirements necessary for proper operation of micro heat pipes. They also provide fundamental insight into the critical mechanisms required for proper heat pipe operation. 29 refs., 6 figs.},
doi = {10.1115/1.2822303},
journal = {Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States)},
number = ,
volume = 117:1,
place = {United States},
year = 1995,
month = 2
}
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