Flow and heat transfer characteristics in a rectangular channel with vortex generators

doi:10.7523/j.issn.2095-6134.2018.02.014

Abstract

Abstract: In this study, effects of longitudinal vortex generator configurations (Case A-F) on the heat transfer and flow friction characteristics in a rectangular channel are investigated using numerical method. The results show that longitudinal vortex generator enhances the heat transfer performance, compared with the smooth channel. The field synergy principle analyses indicate that the intersection angles between velocity and temperature gradient of all longitudinal vortex generator configurations are smaller than that of smooth channel, and the comparison results show that at the same Reynolds number the smaller synergy angle the larger the Nusselt number is completely consistent with the field synergy principle. Comparisons of the performance evaluation parameter, JF factor, indicate that Case F has the best overall heat transfer performance and that Case F brings about more enhancement of heat transfer at a modest expense of the additional pressure. Therefore, Case F is a suitable configuration for enhancing the overall heat transfer performance for channels.

Key words: rectangular channel, longitudinal vortex generator, flow and heat transfer, field synergy principle

CLC Number:

TK124

TANG Linghong, ZENG Min. Flow and heat transfer characteristics in a rectangular channel with vortex generators[J]. , 2018, 35(2): 240-247.

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