Thermal Performance Improvement in Square Duct with Inclined Ribs Inserted Diagonally

Authors

  • Amnart Boonloi King Mongkut’s University of Technology North Bangkok

Keywords:

heat transfer, square-duct, full rib, discrete rib

Abstract

In the current work, a numerical simulation is performed to investigate periodic laminar flow and heat transfer characteristics in a square channel with diagonally 45° fullribbed and discreteribbed tape inserts. The rib height (b/H, BR) is in a range of 0.1 to 0.3 with a single pitch ratio of 1.0. The uniform heat-flux condition is applied to the duct walls. The computations based on the finite volume method and the SIMPLE algorithm has been implemented. Air is used as the test fluid with the airflow rate in terms of Reynolds number ranging from 4000 to 20,000. The numerical results are obtained from using the RNG kε turbulence model. Effects of ribbedtape inserts on heat transfer and pressure loss in the tube are examined and their results are also compared with the smooth tube. The numerical results reveal that the tube with inclinedribbed tape inserts gives the heat transfer rate and pressure loss higher than the smooth tube. The fullribbed tape performs slightly better than the discrete one. In addition, the TEF is found to be about 1  1.25 and 1  1.22 for the fullribbed and the discreteribbed tapes, respectively.

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Published

2015-04-17

How to Cite

Boonloi, A. (2015). Thermal Performance Improvement in Square Duct with Inclined Ribs Inserted Diagonally. Asian Journal of Applied Sciences, 3(2). Retrieved from https://www.ajouronline.com/index.php/AJAS/article/view/2450

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