A numerical investigation of conjugated-natural convection heat transfer enhancement of a nanofluid in an annular tube driven by inner heat generating solid cylinder

Mina Shahi*, Amir Houshang Mahmoudi, Farhad Talebi

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

31 Citations (Scopus)


Laminar conjugate heat transfer by natural convection and conduction in a vertical annulus formed between an inner heat generating solid circular cylinder and an outer isothermal cylindrical boundary has been studied by a numerical method. It is assumed that the two sealed ends of the tube to be adiabatic. Governing equations are derived based on the conceptual model in the cylindrical coordinate system. The governing equations have been solved using the finite volume approach, using SIMPLE algorithm on the collocated arrangement. Results are presented for the flow and temperature distributions and Nusselt numbers on different cross sectional planes and longitudinal sections for Rayleigh number ranging from 105 to 108, solid volume fraction of 0<Φ<0.05 with copper-water nanofluid as the working medium. Considering that the driven flow in the annular tube is strongly influenced by orientation of tube, study has been carried out for different inclination angles.

Original languageEnglish
Pages (from-to)533-542
Number of pages10
JournalInternational Communications in Heat and Mass Transfer
Issue number4
Publication statusPublished - Apr 2011
Externally publishedYes


  • Annular tube
  • Conjugated- Natural convection heat transfer
  • Heat generating solid rod
  • Nanofluid
  • Numerical method
  • Solid concentration
  • Volumetric heat generation

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