Heat transfer characteristics of staggered wing-shaped tubes bundle at different angles of attack

• Published in: Heat and mass transfer Vol. 50; no. 8; pp. 1091 - 1102
• Main Authors: Sayed Ahmed, Sayed Ahmed E., Ibrahiem, Emad Z., Mesalhy, Osama M., Abdelatief, Mohamed A.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-08-2014
• Subjects: Engineering; Engineering Thermodynamics; Heat and Mass Transfer; Industrial Chemistry/Chemical Engineering; Original; Thermodynamics; Heat Transfer Characteristic; Heat Transfer; Heat Exchanger; Heat Transfer Rate; Tube Bundle
• ISSN: 0947-7411; 1432-1181
• DOI: 10.1007/s00231-014-1323-3

An experimental and numerical study has been conducted to clarify heat transfer characteristics and effectiveness of a cross-flow heat exchanger employing staggered wing-shaped tubes at different angels of attack. The water-side Re
w
and the air-side Re
a
were at 5 × 10
2
and at from 1.8 × 10
3
to 9.7 × 10
3
, respectively. The tubes arrangements were employed with various angles of attack θ
1,2,3
from 0° to 330° at the considered Re
a
range. Correlation of Nu, St, as well as the heat transfer per unit pumping power (ε) in terms of Re
a
and design parameters for the studied bundle were presented. The temperature fields around the staggered wing-shaped tubes bundle were predicted by using commercial CFD FLUENT 6.3.26 software package. Results indicated that the heat transfer increased with the angle of attack in the range from 0° to 45°, while the opposite was true for angles of attack from 135° to 180°. The best thermal performance and hence the efficiency η of studied bundle occurred at the lowest Re
a
and/or zero angle of attack. Comparisons between the experimental and numerical results of the present study and those, previously, obtained for similar available studies showed good agreements.