Numerical Investigation of Mixed Convection and Entropy Generation in a Wavy-Walled Cavity Filled with Nanofluid and Involving a Rotating Cylinder

This numerical study considers the mixed convection and the inherent entropy generated in Al2O3–water nanofluid filling a cavity containing a rotating conductive cylinder. The vertical walls of the cavity are wavy and are cooled isothermally. The horizontal walls are thermally insulated, except for a heat source segment located at the bottom wall. The dimensionless governing equations subject to the selected boundary conditions are solved numerically using the Galerkin finite-element method. The study is accomplished by inspecting different ranges of the physical and geometrical parameters, namely, the Rayleigh number (103≤Ra≤106), angular rotational velocity (0≤Ω≤750), number of undulations (0≤N≤4), volume fraction of Al2O3 nanoparticles (0≤ϕ≤0.04), and the length of the heat source (0.2≤H≤0.8). The results show that the rotation of the cylinder boosts the rate of heat exchange when the Rayleigh number is less than 5×105. The number of undulations affects the average Nusselt number for a still cylinder. The rate of heat exchange increases with the volume fraction of the Al2O3 nanoparticles and the length of the heater segment.

[1]  Gh.R. Kefayati,et al.  Double-diffusive laminar natural convection and entropy generation of Carreau fluid in a heated enclosure with an inner circular cold cylinder (Part II: Entropy generation) , 2018 .

[2]  W. Liu,et al.  Natural convection heat transfer of alumina-water nanofluid in vertical square enclosures: An experimental study , 2010 .

[3]  Rehena Nasrin,et al.  Combined convection flow in triangular wavy chamber filled with water–CuO nanofluid: Effect of viscosity models , 2012 .

[4]  Vitor A. F. Costa,et al.  Steady mixed convection in a differentially heated square enclosure with an active rotating circular cylinder , 2010 .

[5]  XueTao Cheng,et al.  Discussion on the applicability of entropy generation minimization to the analyses and optimizations of thermodynamic processes , 2013 .

[6]  C. Chon,et al.  Empirical correlation finding the role of temperature and particle size for nanofluid (Al2O3) thermal conductivity enhancement , 2005 .

[7]  Saman Rashidi,et al.  Volume of fluid model to simulate the nanofluid flow and entropy generation in a single slope solar still , 2018 .

[8]  Marta Cianfrini,et al.  Two-phase mixture modeling of natural convection of nanofluids with temperature-dependent properties , 2013 .

[9]  Ammar Ben Brahim,et al.  Entropy Generation at Natural Convection in an Inclined Rectangular Cavity , 2011, Entropy.

[10]  Kenneth E. Torrance,et al.  Cavity flows driven by buoyancy and shear , 1972, Journal of Fluid Mechanics.

[11]  Yasin Varol,et al.  Free convection in a shallow wavy enclosure , 2006 .

[12]  Liwu Fan,et al.  Laminar mixed convection heat transfer of SiC-EG nanofluids in a triangular enclosure with a rotating inner cylinder: simulations based on the measured thermal conductivity and viscosity , 2015 .

[13]  Man Yeong Ha,et al.  Effect of the position of a circular cylinder in a square enclosure on natural convection at Rayleigh number of 107 , 2009 .

[14]  Saman Rashidi,et al.  Sensitivity Analysis of Entropy Generation in Nanofluid Flow inside a Channel by Response Surface Methodology , 2016, Entropy.

[15]  Rehena Nasrin,et al.  Investigation of buoyancy-driven flow and heat transfer in a trapezoidal cavity filled with water–Cu nanofluid ☆ , 2012 .

[16]  Yasin Varol,et al.  Natural convection in wavy enclosures with volumetric heat sources , 2011 .

[17]  Mohamed Bouzit,et al.  Analysis of mixed convection in an inclined lid-driven cavity with a wavy wall , 2013 .

[18]  P. Lettieri,et al.  An introduction to heat transfer , 2007 .

[19]  Rozaini Roslan,et al.  Effect of rotating cylinder on heat transfer in a square enclosure filled with nanofluids , 2012 .

[20]  Adrian Bejan,et al.  Second-Law Analysis in Heat Transfer and Thermal Design , 1982 .

[21]  Guanshui Xu,et al.  The Effects of Perforation Erosion on Practical Hydraulic-Fracturing Applications , 2017 .

[22]  Ali J. Chamkha,et al.  Conjugate heat transfer and entropy generation in a cavity filled with a nanofluid-saturated porous media and heated by a triangular solid , 2016 .

[23]  A. Bejan.  A Study of Entropy Generation in Fundamental Convective Heat Transfer , 1979 .

[24]  Boqi Xiao,et al.  Prediction Of Convective Heat Transfer Of Nanofluids Based On Fractal-Monte Carlo Simulations , 2013 .

[25]  Aroon Shenoy,et al.  Convective Flow and Heat Transfer from Wavy Surfaces: Viscous Fluids, Porous Media, and Nanofluids , 2016 .

[26]  M. Corcione.  Empirical correlating equations for predicting the effective thermal conductivity and dynamic viscosity of nanofluids , 2011 .

[27]  Muneer A. Ismael,et al.  Numerical solution of mixed convection in a lid-driven cavity with arc-shaped moving wall , 2017 .

[28]  Chao-An Lin,et al.  Mixed convection of a heated rotating cylinder in a square enclosure , 2014 .

[29]  Ioan Pop,et al.  Analysis of Entropy Generation in Natural Convection of Nanofluid inside a Square Cavity Having Hot Solid Block: Tiwari and Das' Model , 2015, Entropy.

[30]  Wu-Shung Fu,et al.  Enhancement of natural convection heat transfer of an enclosure by a rotating circular cylinder , 1994 .

[31]  R. Ellahi,et al.  Optimization of mixed convection heat transfer with entropy generation in a wavy surface square lid-driven cavity by means of Taguchi approach , 2016 .

[32]  Abdalla M. Al-Amiri,et al.  Numerical simulation of combined thermal and mass transport in a square lid-driven cavity , 2007 .

[33]  Ali J. Chamkha,et al.  Effect of rotating solid cylinder on entropy generation and convective heat transfer in a wavy porous cavity heated from below , 2018, International Communications in Heat and Mass Transfer.

[34]  Ishak Hashim,et al.  Entropy Generation Analysis and Natural Convection in a Nanofluid-Filled Square Cavity with a Concentric Solid Insert and Different Temperature Distributions , 2018, Entropy.

[35]  Saman Rashidi,et al.  Influences of wavy wall and nanoparticles on entropy generation over heat exchanger plat , 2017 .

[36]  Ali J. Chamkha,et al.  Effect of spatial side-wall temperature variation on transient natural convection of a nanofluid in a trapezoidal cavity , 2017 .

[37]  Ali J. Chamkha,et al.  Mixed convection of Al2O3-water nanofluid in a double lid-driven square cavity with a solid inner insert using Buongiorno’s two-phase model , 2018 .

[38]  Ali J. Chamkha,et al.  Mixed convection flow of a nanofluid in a lid-driven cavity with a wavy wall , 2014 .

[39]  Ali J. Chamkha,et al.  Entropy Generation and Natural Convection of CuO-Water Nanofluid in C-Shaped Cavity under Magnetic Field , 2016, Entropy.

[40]  Her-Terng Yau,et al.  Enhancement of natural convection heat transfer in a U-shaped cavity filled with Al2O3-water nanofluid , 2012 .

[41]  Ali J. Chamkha,et al.  Effects of heat sink and source and entropy generation on MHD mixed convection of a Cu-water nanofluid in a lid-driven square porous enclosure with partial slip , 2017 .

[42]  Ali J. Chamkha,et al.  Mixed convection in a lid-driven square cavity with partial slip , 2014 .

[43]  Jianchao Cai,et al.  Research on Relative Permeability of Nanofibers with Capillary Pressure Effect by Means of Fractal-Monte Carlo Technique , 2017 .

[44]  A. Bejan.  Entropy Generation Minimization: The Method of Thermodynamic Optimization of Finite-Size Systems and Finite-Time Processes , 1995 .

[45]  Roydon Andrew Fraser,et al.  FREE CONVECTION AND ENTROPY GENERATION INSIDE A VERTICAL INPHASE WAVY CAVITY , 2004 .

[46]  Jae Min Hyun,et al.  Mixed convection in a driven cavity with a stable vertical temperature gradient , 1993 .

[47]  S. Kashani,et al.  Entropy generation and natural convection of nanoparticle-water mixture (nanofluid) near water density inversion in an enclosure with various patterns of vertical wavy walls , 2014, Appl. Math. Comput..

[48]  Rehena Nasrin,et al.  Influences of Physical Parameters on Mixed Convection in a Horizontal Lid-Driven Cavity with an Undulating Base Surface , 2012 .

[49]  Ali J. Chamkha,et al.  Mixed convection in superposed nanofluid and porous layers in square enclosure with inner rotating cylinder , 2017 .

[50]  Dengwei Jing,et al.  Optimization of a circular-wavy cavity filled by nanofluid under the natural convection heat transfer condition , 2016 .

[51]  Bittagopal Mondal,et al.  Hydromagnetic Mixed Convective Transport in a Vertical Lid-Driven Cavity Including a Heat Conducting Rotating Circular Cylinder , 2014 .

[52]  Ningqun Guo,et al.  Entropy generation of viscous dissipative nanofluid flow in thermal non-equilibrium porous media embedded in microchannels , 2015 .

[53]  Chao-An Lin,et al.  Influence of Prandtl number on the instability of natural convection flows within a square enclosure containing an embedded heated cylinder at moderate Rayleigh number , 2015 .

[54]  Bengt Sundén,et al.  Effect of aspect ratio on entropy generation in a rectangular cavity with differentially heated vertical walls , 2008 .

[55]  Omar Imine,et al.  Laminar natural convection in an inclined cavity with a wavy wall , 2002 .

[56]  Jae Min Hyun,et al.  Analyses of three-dimensional flow calculations in a driven cavity , 1990 .

[57]  Ioan Pop,et al.  Magnetic field effect on the unsteady natural convection in a wavy-walled cavity filled with a nanofluid: Buongiorno's mathematical model , 2016 .

[58]  Ilyas Khan,et al.  Analysis of Entropy Generation in Flow of Methanol-Based Nanofluid in a Sinusoidal Wavy Channel , 2017, Entropy.

[59]  Ali J. Chamkha,et al.  MIXED CONVECTION IN A VERTICALLY LAYERED FLUID-POROUS MEDIUM ENCLOSURE WITH TWO INNER ROTATING CYLINDERS , 2017 .

[60]  Wei Wang,et al.  OPTIMIZATION OF THE FRACTAL-LIKE ARCHITECTURE OF POROUS FIBROUS MATERIALS RELATED TO PERMEABILITY, DIFFUSIVITY AND THERMAL CONDUCTIVITY , 2017 .

[61]  Wei Wang,et al.  A FRACTAL MODEL FOR WATER FLOW THROUGH UNSATURATED POROUS ROCKS , 2018 .

[62]  Ali J. Chamkha,et al.  Mixed convection in a partially layered porous cavity with an inner rotating cylinder , 2016 .

[63]  Her-Terng Yau,et al.  Numerical Investigation into Natural Convection and Entropy Generation in a Nanofluid-Filled U-Shaped Cavity , 2015, Entropy.