Thermo-hydraulic Performance of a Circular Tube Heat Exchanger with Combined Turbulators

Authors

  • Amnart Boonloi

Keywords:

heat exchanger, combined turbulators, thermal performance, V-baffle, wavy surface

Abstract

This article presents numerical investigations on heat transfer behaviors, flow configurations and thermal performance assessments in a circular tube heat exchanger with combined turbulators. The combined turbulators; wavy plate with 30o V–baffle, are selected to enhance the heat transfer rate in the tube heat exchanger. The effects of the blockage ratios; b/D = BR, and flow directions; V–tip pointing downstream (called V–Downstream) and V–tip pointing upstream (called V–Upstream), for the baffles are investigated for the Reynolds number based on the diameter of the test tube, Re = 100 – 1200. The numerical results are presented in terms of flow configurations, heat transfer characteristics and performance evaluations and also compared with the smooth tube. It is found that the use of the combined turbulators can help to improve the thermal performance in the heating system due to the longitudinal vortex flows and the disturbance of the thermal boundary layer. In addition, the maximum TEF is found to be around 2.3 at the highest Reynolds number for the combined turbulators with BR = 0.20 and V-tip pointing downstream.

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Published

2016-04-16

How to Cite

Boonloi, A. (2016). Thermo-hydraulic Performance of a Circular Tube Heat Exchanger with Combined Turbulators. Asian Journal of Applied Sciences, 4(2). Retrieved from https://www.ajouronline.com/index.php/AJAS/article/view/3742

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