Heat Transfer Performance in Double-Pass Flat-Plate Heat Exchangers with External Recycle

Ho-Ming  Yeh

doi:10.6180/jase.2014.17.3.10

Heat Transfer Performance in Double-Pass Flat-Plate Heat Exchangers with External Recycle

Ho-Ming Yeh This email address is being protected from spambots. You need JavaScript enabled to view it.¹

¹Energy and Opto-Electronic Materials Research Center, Department of Chemical and Materials Engineering, Tamkang University, Tamsui, Taiwan 251, R.O.C.

Received: August 30, 2011
Accepted: June 12, 2014
Publication Date: September 1, 2014

Download Citation: ||https://doi.org/10.6180/jase.2014.17.3.10

ABSTRACT

The effect of external recycle on the performance in double-pass rectangular heat exchangers was investigated. Theoretical equations for heat transfer rate were derived base on the effectivenesseffect analysis. In constrast to a single-pass device without recycle, improvement in heat transfer of more than 20% is achievable if parallel-flow heat exchange is operated in a double-pass device of same size with external recycle which provides the increase of fluid velocity, resulting in reduction of heat-transfer resistance. It is found that the performances obtained in the double-pass devices with external recycle operating under concurrent and countercurrent flows are exactly the same.

Keywords: Heat Transfer, External Recycle, Effectiveness-Factor Analysis, Double Pass, Heat Exchanger, Performance Improved

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