TURBULENT FLOW AND HEAT TRANSFER CHARACTERISTICS IN U-TUBES: A NUMERICAL STUDY

Abstract

Using the standard k-e model, 3-dimensional turbulent flow and heat transfer characteristics in U-tubes are investigated. Uncertainty is approximated using experimental correlations and grid independence study. Increasing the Dean number is shown to intensify a secondary flow within the curved section. The overall Nusselt number for the tube is found to decrease substantially relative to straight tubes, while the overall skin friction coefficient remains practically unaffected. Local skin friction coefficient, Nusselt number, and wall temperature along the tube wall are presented.

Keywords

Dates

  • Submission Date2008-05-25
  • Revision Date2008-10-01
  • Acceptance Date2008-11-11

DOI Reference

10.2298/TSCI0904175A

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