Heat Transfer Augmentation in a Round Tube with 60^o Winglet Pair Inserts

Abstract:

The experimental study on heat transfer enhancement in a tubular heat exchanger fitted with 60^o winglet pairs is carried out by varying airflow velocity in turbulent region in the test section having a constant wall heat-flux. Effects of three blockage ratios (BR=e/D= 0.1, 0.15 and 0.2) and three pitch ratios (PR=P/D= 1, 1.5 and 2) of the winglet pairs on heat transfer rates in the terms of Nusselt number (Nu) and pressure loss in the form of friction factor (f) are examined. The experimental results illustrated that the tube with winglet pair insert provides the heat transfer rate higher than the smooth tube around 1.7 to 2.6 times, depending upon operating conditions. The thermal enhancement factor for using the winglet-pair turbulator is in a range of 1.03 - 1.31.

• Periodical: Advanced Materials Research (Volumes 931-932)
• Pages: 1188-1192
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.931-932.1188
• Online since: May 2014
• Authors: Suriya Chokphoemphun, Pattarapan Tongyote, Pongjet Promvonge*, Withada Jedsadaratanachai, Teerapat Chompookham
• Keywords: Counter-Vortex, Friction Factor, Nusselt Number, Thermal Performance, Winglet

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