Experimental Investigation of the Air Flow Behavior and Heat Transfer Characteristics in Microchannels With Different Channel LengthsSource: Journal of Heat Transfer:;2017:;volume( 139 ):;issue: 005::page 52403DOI: 10.1115/1.4035589Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: This paper attempts to experimentally investigate the influence of channel length on the flow behavior and heat transfer characteristics in circular microchannels. The diameters of the channels were 0.4 mm and the length of them were 5 mm, 10 mm, 15 mm, and 20 mm, respectively. All experiments were performed with air and completed with Reynolds number in the range of 300–2700. Results of the experiments show that the length of microchannels has remarkable effects on the performance of flow behavior and heat transfer characteristics. Both the friction factor and Poiseuille number drop with the increase of channel length, and the experimental values are higher than the theoretical ones. Moreover, the channel length does not influence the value of critical Reynolds number. Nusselt number decrease as the increase of channel length. Larger Nusselt numbers are obtained in shorter channels. The results also indicate that in all cases, the friction factor decreases and the Poiseuille number increases with the increase of the Reynolds number. It is also observed that the value of critical Reynolds number is between 1500 and 1700 in this paper, which is lower than the value of theoretical critical Reynolds number of 2300.
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contributor author | Tao, Zhi | |
contributor author | Zhu, Zhibing | |
contributor author | Li, Haiwang | |
date accessioned | 2017-11-25T07:16:50Z | |
date available | 2017-11-25T07:16:50Z | |
date copyright | 2017/14/2 | |
date issued | 2017 | |
identifier issn | 0022-1481 | |
identifier other | ht_139_05_052403.pdf | |
identifier uri | http://138.201.223.254:8080/yetl1/handle/yetl/4234232 | |
description abstract | This paper attempts to experimentally investigate the influence of channel length on the flow behavior and heat transfer characteristics in circular microchannels. The diameters of the channels were 0.4 mm and the length of them were 5 mm, 10 mm, 15 mm, and 20 mm, respectively. All experiments were performed with air and completed with Reynolds number in the range of 300–2700. Results of the experiments show that the length of microchannels has remarkable effects on the performance of flow behavior and heat transfer characteristics. Both the friction factor and Poiseuille number drop with the increase of channel length, and the experimental values are higher than the theoretical ones. Moreover, the channel length does not influence the value of critical Reynolds number. Nusselt number decrease as the increase of channel length. Larger Nusselt numbers are obtained in shorter channels. The results also indicate that in all cases, the friction factor decreases and the Poiseuille number increases with the increase of the Reynolds number. It is also observed that the value of critical Reynolds number is between 1500 and 1700 in this paper, which is lower than the value of theoretical critical Reynolds number of 2300. | |
publisher | The American Society of Mechanical Engineers (ASME) | |
title | Experimental Investigation of the Air Flow Behavior and Heat Transfer Characteristics in Microchannels With Different Channel Lengths | |
type | Journal Paper | |
journal volume | 139 | |
journal issue | 5 | |
journal title | Journal of Heat Transfer | |
identifier doi | 10.1115/1.4035589 | |
journal fristpage | 52403 | |
journal lastpage | 052403-7 | |
tree | Journal of Heat Transfer:;2017:;volume( 139 ):;issue: 005 | |
contenttype | Fulltext |