A study of natural convection heat transfer in a nanofluid filled enclosure with elliptic inner cylinder

– The purpose of this paper is to study the effects of natural convection heat transfer in a cold outer circular enclosure containing a hot inner elliptic circular cylinder. The fluid in the enclosure is Cu-water nanofluid. The main emphasis is to find the numerical treatment for the said mathematical model. The effects of Rayleigh number, inclined angle of elliptic inner cylinder, effective of thermal conductivity and viscosity of nanofluid, volume fraction of nanoparticles on the flow and heat transfer characteristics have been examined. , – A very effective and higher order numerical scheme Control Volume-based Finite Element Method (CVFEM) is used to solve the resulting coupled equations. The numerical investigation is carried out for different governing parameters namely; the Rayleigh number, nanoparticle volume fraction and inclined angle of elliptic inner cylinder. The effective thermal conductivity and viscosity of nanofluid are calculated using the Maxwell-Garnetts (MG) and Brinkman models, respectively. , – The results reveal that Nusselt number increases with an increase of nanoparticle volume fraction, Rayleigh numbers and inclination angle. Also it can be found that increasing Rayleigh number leads to a decrease in heat transfer enhancement. For high Rayleigh number the minimum heat transfer enhancement ratio occurs at. , – To the best of the authors’ knowledge, no such analysis is available in the literature which can describe the natural convection heat transfer in a nanofluid filled enclosure with elliptic inner cylinder by means of CVFEM.

[1]  N. K. Ghaddar.  Natural convection heat transfer between a uniformly heated cylindrical element and its rectangular enclosure , 1992 .

[2]  Ioan Pop,et al.  Numerical study of natural convection between a circular enclosure and a sinusoidal cylinder using control volume based finite element method , 2013 .

[3]  N. Akbar,et al.  Mixed Convective Magnetohydrodynamic Peristaltic Flow of a Jeffrey Nanofluid with Newtonian Heating , 2013 .

[4]  Davood Domiri Ganji,et al.  Natural convection in a nanofluid filled concentric annulus between an outer square cylinder and an inner elliptic cylinder , 2013 .

[5]  Richard J Goldstein,et al.  An experimental and theoretical study of natural convection in the annulus between horizontal concentric cylinders , 1976, Journal of Fluid Mechanics.

[6]  Stephen U. S. Choi,et al.  Role of Brownian motion in the enhanced thermal conductivity of nanofluids , 2004 .

[7]  Eiyad Abu-Nada,et al.  Effects of variable viscosity and thermal conductivity of Al2O3-water nanofluid on heat transfer enhancement in natural convection , 2009 .

[8]  R. Prasher,et al.  Thermal conductivity of nanoscale colloidal solutions (nanofluids). , 2005, Physical review letters.

[9]  Mohammad Mehdi Rashidi,et al.  COMPARATIVE NUMERICAL STUDY OF SINGLE-PHASE AND TWO-PHASE MODELS FOR BIO-NANOFLUID TRANSPORT PHENOMENA , 2014 .

[10]  Mohammad Mehdi Rashidi,et al.  Magnetohydrodynamic biorheological transport phenomena in a porous medium: A simulation of magnetic blood flow control and filtration , 2011 .

[11]  Tasawar Hayat,et al.  Peristaltic flow of a nanofluid in a non-uniform tube , 2012 .

[12]  Clement Kleinstreuer,et al.  Laminar nanofluid flow in microheat-sinks , 2005 .

[13]  Davood Domiri Ganji,et al.  Magnetic field effect on nanofluid flow and heat transfer using KKL model , 2014 .

[14]  Davood Domiri Ganji,et al.  Effect of a magnetic field on natural convection in an inclined half-annulus enclosure filled with Cu–water nanofluid using CVFEM , 2013 .

[15]  Davood Domiri Ganji,et al.  Natural convection heat transfer in a nanofluid filled semi-annulus enclosure ☆ , 2012 .

[16]  M. Gorji-Bandpy,et al.  Two phase simulation of nanofluid flow and heat transfer using heatline analysis , 2013 .

[17]  Davood Domiri Ganji,et al.  Magnetic field effects on natural convection around a horizontal circular cylinder inside a square enclosure filled with nanofluid , 2012 .

[18]  Davood Domiri Ganji,et al.  Application of LBM in simulation of natural convection in a nanofluid filled square cavity with curve boundaries , 2013 .

[19]  J. Koo,et al.  Viscous dissipation effects in microtubes and microchannels , 2004 .

[20]  Rahmat Ellahi,et al.  Series solutions of non-Newtonian nanofluids with Reynolds' model and Vogel's model by means of the homotopy analysis method , 2012, Math. Comput. Model..

[21]  Rozaini Roslan,et al.  Natural convection heat transfer in a nanofluid-filled trapezoidal enclosure , 2011 .

[22]  Davood Domiri Ganji,et al.  Numerical investigation of MHD effects on Al2O3–water nanofluid flow and heat transfer in a semi-annulus enclosure using LBM , 2013 .

[23]  R. Ellahi.  The effects of MHD and temperature dependent viscosity on the flow of non-Newtonian nanofluid in a pipe: Analytical solutions , 2013 .

[24]  Davood Domiri Ganji,et al.  Nanofluid flow and heat transfer in a rotating system in the presence of a magnetic field , 2014 .

[25]  Saeed Zeinali Heris,et al.  HEAT TRANSFER ENHANCEMENT USING AL2O3/WATER NANOFLUID IN A TWO-PHASE CLOSED THERMOSYPHON , 2009 .

[26]  Davood Domiri Ganji,et al.  Analytical investigation of MHD nanofluid flow in a semi-porous channel , 2013 .

[27]  Mohammad Mehdi Rashidi,et al.  Entropy generation in steady MHD flow due to a rotating porous disk in a nanofluid , 2013 .

[28]  Davood Domiri Ganji,et al.  Natural convection of nanofluids in an enclosure between a circular and a sinusoidal cylinder in the presence of magnetic field , 2012 .

[29]  M. Esfahany,et al.  Experimental investigation of turbulent convective heat transfer of dilute γ-Al2O3/water nanofluid inside a circular tube , 2010 .

[30]  Eiyad Abu-Nada,et al.  Effects of inclination angle on natural convection in enclosures filled with Cu–water nanofluid , 2009 .

[31]  Davood Domiri Ganji,et al.  Natural convection heat transfer in a cavity with sinusoidal wall filled with CuO–water nanofluid in presence of magnetic field , 2014 .

[32]  S. Haldar.  Combined convection in developing flow through a horizontal concentric annulus , 1998 .

[33]  Ziyad N. Masoud,et al.  Natural convection heat transfer enhancement in horizontal concentric annuli using nanofluids , 2008 .

[34]  M. Gorji-Bandpy,et al.  Free convection of nanofluid filled enclosure using lattice Boltzmann method (LBM) , 2013 .

[35]  Rahmat Ellahi,et al.  Numerical analysis of steady non‐Newtonian flows with heat transfer analysis, MHD and nonlinear slip effects , 2012 .

[36]  Davood Domiri Ganji,et al.  Effect of magnetic field on Cu–water nanofluid heat transfer using GMDH-type neural network , 2013, Neural Computing and Applications.

[37]  Sohail Nadeem,et al.  Endoscopic Effects on Peristaltic Flow of a Nanofluid , 2011 .

[38]  Davood Domiri Ganji,et al.  Nanofluid Flow in a Semi-porous Channel in the Presence of Uniform Magnetic Field , 2013 .

[39]  Rahmat Ellahi,et al.  Effects of MHD on Cu–water nanofluid flow and heat transfer by means of CVFEM , 2014 .

[40]  B. R. Baliga,et al.  A CONTROL VOLUME FINITE-ELEMENT METHOD FOR TWO-DIMENSIONAL FLUID FLOW AND HEAT TRANSFER , 1983 .

[41]  Tasawar Hayat,et al.  Peristaltic flow of a nanofluid with slip effects , 2012 .

[42]  Amgad Salama,et al.  Effect of thermal dispersion on free convection in a fluid saturated porous medium , 2009 .

[43]  N. Akbar,et al.  Peristaltic flow of a Phan-Thien-Tanner nanofluid in a diverging tube , 2012 .

[44]  Sohail Nadeem,et al.  Analytical and Numerical Analysis of Vogel’s Model of Viscosity on the Peristaltic Flow of Jeffrey Fluid , 2012 .

[45]  Davood Domiri Ganji,et al.  Heat transfer of Cu-water nanofluid flow between parallel plates , 2013 .

[46]  I. Hashim,et al.  Numerical Investigation of the Effect of Magnetic Field on Natural Convection in a Curved-Shape Enclosure , 2013 .

[47]  K. Khanafer,et al.  BUOYANCY-DRIVEN HEAT TRANSFER ENHANCEMENT IN A TWO-DIMENSIONAL ENCLOSURE UTILIZING NANOFLUIDS , 2003 .

[48]  Davood Domiri Ganji,et al.  MHD natural convection in a nanofluid filled inclined enclosure with sinusoidal wall using CVFEM , 2012, Neural Computing and Applications.