Flow and Heat Transfer Characteristics of a Natural Circulation Evaporative Cooling System for Electronic ComponentsSource: Journal of Electronic Packaging:;2004:;volume( 126 ):;issue: 003::page 317DOI: 10.1115/1.1772412Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Experiments were conducted to study the flow and heat transfer characteristics of a natural circulation liquid cooling system for electronic components. The test loop consisted of a horizontal test section, a horizontal evaporator, a vertical tube, a horizontal condenser, a rubber bag attached at the exit of the condenser, a downcomer, a mass flow meter, and a liquid subcooler. The loop height H was set at either 250 or 450 mm. FC-72 was filled in the test loop up to some level of loop height and the upper part was filled with air. During the operation of the cooling system, the rubber bag expanded and stored the mixture of generated vapor and air. Thus the inner pressure was maintained at atmospheric pressure. In the test section, a silicon chip with dimensions of 10×10×0.5 mm3 was attached at the bottom surface of a horizontal duct with dimensions of 10×14 mm2 . A smooth chip and four chips with square micro-pin-fins with 150 to 300 μm in fin height were tested. The duct height s was set at 10 mm for most of the experiments. The cases of s=1 and 25 mm were also tested for one of the micro-pin-finned chips. For each H, the average flow rate of FC-72 was correlated well as a function of the static pressure difference between the two vertical tubes. All chips showed the boiling curve similar to that for pool boiling except that the critical heat flux was lower for the natural circulation loop. For all chips tested, the maximum allowable heat flux qmax increased monotonically with increasing liquid subcooling ΔTsub. Comparison of the results for s=1, 10 and 25 mm revealed that the highest qmax was obtained with s=10 mm. The values of qmax for s=1 and 25 mm were 36–46% and 87–90% of that for s=10 mm, respectively. The maximum value of qmax=56 W/cm2 was obtained by one of the micro-pin-finned chips at s=10 mm and ΔTsub=35 K.
keyword(s): Flow (Dynamics) , Heat transfer , Vapors , Boiling , Electronic components , Condensers (steam plant) , Ducts , Pool boiling , Heat flux , Critical heat flux , Evaporative cooling , Cooling systems , Fins , Subcooling , Temperature , Cooling , Water , Pressure , Rubber AND Flowmeters ,
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contributor author | Hiroshi Honda | |
contributor author | ZhengGuo Zhang | |
contributor author | Nobuo Takata | |
date accessioned | 2017-05-09T00:12:42Z | |
date available | 2017-05-09T00:12:42Z | |
date copyright | September, 2004 | |
date issued | 2004 | |
identifier issn | 1528-9044 | |
identifier other | JEPAE4-26235#317_1.pdf | |
identifier uri | http://yetl.yabesh.ir/yetl/handle/yetl/129851 | |
description abstract | Experiments were conducted to study the flow and heat transfer characteristics of a natural circulation liquid cooling system for electronic components. The test loop consisted of a horizontal test section, a horizontal evaporator, a vertical tube, a horizontal condenser, a rubber bag attached at the exit of the condenser, a downcomer, a mass flow meter, and a liquid subcooler. The loop height H was set at either 250 or 450 mm. FC-72 was filled in the test loop up to some level of loop height and the upper part was filled with air. During the operation of the cooling system, the rubber bag expanded and stored the mixture of generated vapor and air. Thus the inner pressure was maintained at atmospheric pressure. In the test section, a silicon chip with dimensions of 10×10×0.5 mm3 was attached at the bottom surface of a horizontal duct with dimensions of 10×14 mm2 . A smooth chip and four chips with square micro-pin-fins with 150 to 300 μm in fin height were tested. The duct height s was set at 10 mm for most of the experiments. The cases of s=1 and 25 mm were also tested for one of the micro-pin-finned chips. For each H, the average flow rate of FC-72 was correlated well as a function of the static pressure difference between the two vertical tubes. All chips showed the boiling curve similar to that for pool boiling except that the critical heat flux was lower for the natural circulation loop. For all chips tested, the maximum allowable heat flux qmax increased monotonically with increasing liquid subcooling ΔTsub. Comparison of the results for s=1, 10 and 25 mm revealed that the highest qmax was obtained with s=10 mm. The values of qmax for s=1 and 25 mm were 36–46% and 87–90% of that for s=10 mm, respectively. The maximum value of qmax=56 W/cm2 was obtained by one of the micro-pin-finned chips at s=10 mm and ΔTsub=35 K. | |
publisher | The American Society of Mechanical Engineers (ASME) | |
title | Flow and Heat Transfer Characteristics of a Natural Circulation Evaporative Cooling System for Electronic Components | |
type | Journal Paper | |
journal volume | 126 | |
journal issue | 3 | |
journal title | Journal of Electronic Packaging | |
identifier doi | 10.1115/1.1772412 | |
journal fristpage | 317 | |
journal lastpage | 324 | |
identifier eissn | 1043-7398 | |
keywords | Flow (Dynamics) | |
keywords | Heat transfer | |
keywords | Vapors | |
keywords | Boiling | |
keywords | Electronic components | |
keywords | Condensers (steam plant) | |
keywords | Ducts | |
keywords | Pool boiling | |
keywords | Heat flux | |
keywords | Critical heat flux | |
keywords | Evaporative cooling | |
keywords | Cooling systems | |
keywords | Fins | |
keywords | Subcooling | |
keywords | Temperature | |
keywords | Cooling | |
keywords | Water | |
keywords | Pressure | |
keywords | Rubber AND Flowmeters | |
tree | Journal of Electronic Packaging:;2004:;volume( 126 ):;issue: 003 | |
contenttype | Fulltext |