Experimental and numerical investigation of nanofluid heat transfer in helically coiled tubes at constant wall temperature using dispersion model

Farzan Akbaridoust, Milad Rakhsha, Abbas Abbassi, Majid Saffar-Avval

Research output: Contribution to journalArticleResearchpeer-review

76 Citations (Scopus)

Abstract

In the present research, laminar, steady state flow in helically coiled tubes at a constant wall temperature was studied numerically and experimentally. Pressure drop and the convective heat transfer behavior of nanofluid were investigated. In the experimental section, a heat exchanger was designed, capable of providing constant wall temperature for coils with different curvature and torsion ratio for the ease of assembly. Pressure drop measurement and average convective heat transfer coefficient calculation were carried out. In the numerical study, the three dimensional governing equations were solved by finite difference method with projection algorithm using FORTRAN programming language. Homogeneous model with constant effective properties was used. The difference between numerical and experimental results was significant. Dispersion model was employed to make the observed difference between numerical and experimental results negligible. Dispersion model was modified to be applicable for helical tubes. This modification resulted in negligible difference between the numerical and the experimental results. More enhanced heat transfer was observed for tubes with greater curvature ratio. Moreover, the performance evaluation of these enhanced heat transfer methods presented. Utilization of base fluid in helical tube with greater curvature compared to the use of nanofluid in straight tubes enhanced heat transfer more effectively.

Original languageEnglish
Pages (from-to)480-491
Number of pages12
JournalInternational Journal of Heat and Mass Transfer
Volume58
Issue number1-2
DOIs
Publication statusPublished - 7 Jan 2013
Externally publishedYes

Keywords

  • Constant wall temperature
  • Experimental setup
  • Helically coiled tube
  • Homogeneous dispersion model
  • Nanofluid
  • Projection algorithm

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