Laminar flow and heat transfer through square duct with twisted tape insert

✍ Scribed by S. Ray; A.W. Date

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 528 KB
• Volume: 22
• Category: Article
• ISSN: 0142-727X
• DOI: 10.1016/s0142-727x(01)00078-9

✦ Synopsis

Numerically predicted characteristics of laminar ¯ow and heat transfer through square duct with twisted tape insert are presented in this paper. The transport equations are solved on a non-staggered non-orthogonal grid using the curvilinear version of the ``Complete Pressure Correction'' algorithm. Both the ¯ow and heat transfer are in a state of periodic development in the axial direction. The heat transfer characteristics are predicted under axially and peripherally constant wall heat ¯ux conditions. Correlations for friction factor and Nusselt number are developed from the predicted data. The agreement between the correlation and experimental data for friction factor is found to be excellent. Relative thermo-hydraulic performance of square and circular ducts, both ®tted with twisted tapes of same twist ratio is also presented in this paper. The study shows signi®cant improvements can be achieved with the square duct, particularly at higher Prandtl numbers and lower twist ratios. Improvement is observed even for air, over certain ranges of Reynolds number.