Thermal management of water based SWCNTs enclosed in a partially heated trapezoidal cavity via FEM

Abstract Present study, examines the phenomena of natural convection flow in a partially heated trapezoidal cavity loaded with the nanofluid in the presence of Single Wall Carbon Nanotubes (SWCNTs). A modified model for effective thermal conductivity of carbon nanotube is used to develop the governing partial differential equations. Thermal management within the cavity is controlled via two simultaneous features: one is to use the partially heated bottom wall and other is to use conductivity of Carbon particles. Most significant and physical conditions are adjusted at the inclined walls of the trapezoidal cavity to obtain the behavior of stream lines and heat management. The Gelerkin finite element method is implemented to solve the dimensionless form of PDEs. Simulations are performed for the different lengths of the heated portion ( 0.3 ⩽ L ⩽ 0.7 ) , various choices of Raleigh number ( 10 4 ⩽ Ra ⩽ 10 7 ) and volume fraction ( 0.0 ⩽ ϕ ⩽ 0.2 ) . Flow field and thermal field are visualized through streamlines and isotherms. Moreover, results are obtained for Nusselt number over partially heated wall, temperature and velocity distribution over the mean position of the cavity. It is found that, by reducing the length of heated portion, flow filed is getting stronger but thermal depicts the opposite trend inside the cavity. Variation of Raleigh number also has significant influence on flow and thermal field. Conduction was dominant at low Ra but later on convection was found to be dominant for large choice. Fluid circulation was stronger and heat transfer rate was very slow at low viscous effects. From the graph it is clear that greater heat transfer will be occurred in the presence of nanofluid as compared to the based fluid water. Similarly velocity distribution of water is dominant as compare to the nanofluid.

[1]  J. Garnett,et al.  Colours in Metal Glasses and in Metallic Films , 1904 .

[2]  Angela Violi,et al.  Natural convection heat transfer of nanofluids in a vertical cavity: Effects of non-uniform particle diameter and temperature on thermal conductivity , 2010 .

[3]  Elif Büyük Öğüt,et al.  Natural convection of water-based nanofluids in an inclined enclosure with a heat source , 2009 .

[4]  M. Das,et al.  Natural convection heat transfer augmentation in a partially heated and partially cooled square cavity utilizing nanofluids , 2009 .

[5]  Jyotirmay Banerjee,et al.  Analysis of flow and thermal field in nanofluid using a single phase thermal dispersion model , 2010 .

[6]  Ioan Pop,et al.  Natural convection in right-angle porous trapezoidal enclosure partially cooled from inclined wall , 2009 .

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

[8]  D. Ganji,et al.  Thermal behavior of longitudinal convective–radiative porous fins with different section shapes and ceramic materials (SiC and Si3N4) , 2014 .

[9]  Tanmay Basak,et al.  Heat flow analysis for natural convection within trapezoidal enclosures based on heatline concept , 2009 .

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

[11]  B. Thang,et al.  A modified model for thermal conductivity of carbon nanotube-nanofluids , 2015 .

[12]  O. Pourmehran,et al.  Statistical optimization of microchannel heat sink (MCHS) geometry cooled by different nanofluids using RSM analysis , 2015 .

[13]  Davood Domiri Ganji,et al.  Electrohydrodynamic flow analysis in a circular cylindrical conduit using Least Square Method , 2014 .

[14]  I. Pop,et al.  Entropy analysis due to conjugate-buoyant flow in a right-angle trapezoidal enclosure filled with a porous medium bounded by a solid vertical wall , 2009 .

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

[16]  Saiied M. Aminossadati,et al.  Magnetic field effect on natural convection in a nanofluid-filled square enclosure , 2011 .

[17]  H. Oztop,et al.  Numerical study of natural convection in partially heated rectangular enclosures filled with nanofluids , 2008 .

[18]  Sheng-Chung Tzeng,et al.  Numerical research of nature convective heat transfer enhancement filled with nanofluids in rectangular enclosures , 2006 .

[19]  P. Hood,et al.  A numerical solution of the Navier-Stokes equations using the finite element technique , 1973 .

[20]  Davood Domiri Ganji,et al.  Study on blood flow containing nanoparticles through porous arteries in presence of magnetic field using analytical methods , 2015 .