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Title: Limits on aspect ratio in two-fluid microscale heat exchangers

Abstract

This research investigates the theoretical limit on aspect ratio within two-fluid counter-flow microchannel heat exchangers. The counter-flow device is comprised of alternating layers of microchannels, which allow the two fluids to flow in opposite directions, separated by fins. A theoretical model for interpreting the span of the fin as a function of the fin thickness is established. The model is verified experimentally by fabricating two kinds of test specimens to simulate the counter-flow device. Results from metallography and leakage testing reveal that for a given set of bonding conditions, there exists a maximum permissible value of elastic fin deflection during bonding beyond which leakage is bound to occur. Furthermore, the results imply that higher aspect ratios can be achieved at smaller scales.

Authors:
 [1];  [1];  [1];
  1. (Oregon State Univ., Corvallis, OR)
Publication Date:
Research Org.:
Oregon State University, Corvallis, OR; Albany Research Center (ARC), Albany, OR
Sponsoring Org.:
US Department of the Navy, Office of Naval Research (ONR)
OSTI Identifier:
923533
Report Number(s):
DOE/ARC-2001-131
TRN: US200804%%1134
DOE Contract Number:
Not cited
Resource Type:
Conference
Resource Relation:
Conference: 29th North American Manufacturing Research Conference (NAMRC XXIX), Gainesville, FL, May 22-25, 2001
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; ASPECT RATIO; HEAT EXCHANGERS; MINIATURIZATION; LIMITING VALUES; COUNTERFLOW SYSTEMS; MATHEMATICAL MODELS; LEAK TESTING; FINS; THICKNESS

Citation Formats

Paul, B.K., Hasan, Hadi, Thomas, J.S., and Wilson, R.D.. Limits on aspect ratio in two-fluid microscale heat exchangers. United States: N. p., 2001. Web.
Paul, B.K., Hasan, Hadi, Thomas, J.S., & Wilson, R.D.. Limits on aspect ratio in two-fluid microscale heat exchangers. United States.
Paul, B.K., Hasan, Hadi, Thomas, J.S., and Wilson, R.D.. Mon . "Limits on aspect ratio in two-fluid microscale heat exchangers". United States. doi:.
@article{osti_923533,
title = {Limits on aspect ratio in two-fluid microscale heat exchangers},
author = {Paul, B.K. and Hasan, Hadi and Thomas, J.S. and Wilson, R.D.},
abstractNote = {This research investigates the theoretical limit on aspect ratio within two-fluid counter-flow microchannel heat exchangers. The counter-flow device is comprised of alternating layers of microchannels, which allow the two fluids to flow in opposite directions, separated by fins. A theoretical model for interpreting the span of the fin as a function of the fin thickness is established. The model is verified experimentally by fabricating two kinds of test specimens to simulate the counter-flow device. Results from metallography and leakage testing reveal that for a given set of bonding conditions, there exists a maximum permissible value of elastic fin deflection during bonding beyond which leakage is bound to occur. Furthermore, the results imply that higher aspect ratios can be achieved at smaller scales.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2001},
month = {Mon Jan 01 00:00:00 EST 2001}
}

Conference:
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