Flow and Heat Transfer in Nanofluid Flow through a Cylinder Filled with Foam Porous Medium under Radial Injection

The Darcy flow and heat convection in nanofluid through a cylinder filled with a foam porous medium subject to local non-thermal equilibrium (LNTE) condition and uniform radial injection on the outer wall of the cylinder is studied. The momentum and two-energy equations are solved by differential transformation method (DTM) in the form of stream function using similarity variables. The effect on flow and heat transfer of different types of nanofluids and involved physical parameters Prandtl number Pr, Reylond number Re, Darcy number Da, Biot number Bi, Ratio of thermal conductivities Rk, porosity parameter ε, solid volume fraction parameter φ and shape of nanoparticles are analyzed through graphs. The viscous drag force and heat convection at the wall of the cylinder is calculated in terms of non-dimensional skin-friction coefficient and Nusselt number respectively. Decreasing the porosity of foam porous medium causes increment in magnitude of heat transfer rate for both the phases. Spherical shape of nanoparticles transfers more heat in comparison of cylindrical shape nanoparticles. Amongst the nanofluid H2O-Ag, H2O-Cu and H2O-Al2O3 the magnitude of heat transfer for fluid phase Nuf is lowest for nanofluid H2O-Al2O3.

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Mixed Convective Flow of Micropolar Nanofluid across a Horizontal Cylinder in Saturated Porous Medium

Applied Sciences ◽

10.3390/app9235241 ◽

2019 ◽

Vol 9 (23) ◽

pp. 5241 ◽

Cited By ~ 6

Author(s):

Ahmed M. Rashad ◽

Waqar A. Khan ◽

Saber M. M. EL-Kabeir ◽

Amal M. A. EL-Hakiem

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Convective Flow ◽

Volume Fraction ◽

Saturated Porous Medium ◽

Titania Nanoparticles ◽

Flow And Heat Transfer ◽

Micropolar Nanofluid ◽

Mixed Convective Flow ◽

The Impact

The micropolar nanofluids are the potential liquids that enhance the thermophysical features and ability of heat transportation instead of base liquids. Alumina and Titania nanoparticles are mixed in a micropolar fluid. The impact of convective boundary condition is also examined with assisting and opposing flows of both nanofluids. The main objective of this study is to investigate mixed convective flow and heat transfer of micropolar nanofluids across a cylinder in a saturated porous medium. Non-similar variables are used to make the governing equations dimensionless. The local similar and non-similar solutions are obtained by using the Runge-Kutta-Fehlberg method of seventh order. The impacts of various embedded variables on the flow and heat transfer of micropolar nanofluids are investigated and interpreted graphically. It is demonstrated that the skin friction and heat transfer rates depend on solid volume fraction of nanoparticles, Biot number, mixed convection, and material parameters.

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Natural convective heat transfer in a hemispherical cavity filled with ZnO–H2O nanofluid saturated porous medium

International Journal of Modern Physics C ◽

10.1142/s0129183118500973 ◽

2018 ◽

Vol 29 (10) ◽

pp. 1850097 ◽

Cited By ~ 5

Author(s):

Abderrahmane Baïri ◽

Najib Laraqi

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Nusselt Number ◽

Rayleigh Number ◽

Convective Heat Transfer ◽

Convective Heat ◽

Volume Fraction ◽

Saturated Porous Medium ◽

Physical Parameters ◽

Numerical Work

This three-dimensional (3D) numerical work based on the volume control method quantifies the convective heat transfer occurring in a hemispherical cavity filled with a ZnO–H2O nanofluid saturated porous medium. Its main objective is to improve the cooling of an electronic component contained in this enclosure. The volume fraction of the considered monophasic nanofluid varies between 0% (pure water) and 10%, while the cupola is maintained isothermal at cold temperature. During operation, the active device generates a heat flux leading to high Rayleigh number reaching [Formula: see text] and may be inclined with respect to the horizontal plane at an angle ranging from 0[Formula: see text] to 180[Formula: see text] (horizontal position with cupola facing upwards and downwards, respectively) by steps of 15[Formula: see text]. The natural convective heat transfer represented by the average Nusselt number has been quantified for many configurations obtained by combining the tilt angle, the Rayleigh number, the nanofluid volume fraction and the ratio between the thermal conductivity of the porous medium’s solid matrix and that of the base fluid. This ratio has a significant influence on the free convective heat transfer and ranges from 0 (without porous media) to 70 in this work. The influence of the four physical parameters is analyzed and commented. An empirical correlation between the Nusselt number and these parameters is proposed, allowing determination of the average natural convective heat transfer occurring in the hemispherical cavity.

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MHD Flow of a Viscous Fluid over an Exponentially Stretching Sheet in a Porous Medium

Journal of Applied Mathematics ◽

10.1155/2014/256761 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Iftikhar Ahmad ◽

Muhmmad Sajid ◽

Wasim Awan ◽

Muhammad Rafique ◽

Wajid Aziz ◽

...

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Differential Equations ◽

Stretching Sheet ◽

Transfer Problem ◽

Heat Transfer Analysis ◽

Physical Parameters ◽

Exponentially Stretching Sheet ◽

Flow And Heat Transfer ◽

Exponentially Stretching

Radiation effects on magnetohydrodynamic (MHD) boundary-layer flow and heat transfer characteristic through a porous medium due to an exponentially stretching sheet have been studied. Formulation of the problem is based upon the variable thermal conductivity. The heat transfer analysis is carried out for both prescribed surface temperature (PST) and prescribed heat flux (PHF) cases. The developed system of nonlinear coupled partial differential equations is transformed to nonlinear coupled ordinary differential equations by using similarity transformations. The series solutions for the transformed of the transformed flow and heat transfer problem were constructed by homotopy analysis method (HAM). The obtained results are analyzed under the influence of various physical parameters.

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MHD Natural Convective Flow in an Isosceles Triangular Cavity Filled with Porous Medium due to Uniform/Non-Uniform Heated Side Walls

Zeitschrift für Naturforschung A ◽

10.1515/zna-2015-0232 ◽

2015 ◽

Vol 70 (11) ◽

pp. 919-928 ◽

Cited By ~ 17

Author(s):

Tariq Javed ◽

Muhammad Arshad Siddiqui ◽

Ziafat Mehmood ◽

Ioan Pop

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Nusselt Number ◽

Bottom Wall ◽

Physical Parameters ◽

Uniform Heating ◽

Weighted Residual Method ◽

Flow And Heat Transfer ◽

Side Walls ◽

Limiting Case

AbstractIn this article, numerical simulations are carried out for fluid flow and heat transfer through natural convection in an isosceles triangular cavity under the effects of uniform magnetic field. The cavity is of cold bottom wall and uniformly/non-uniformly heated side walls and is filled with isotropic porous medium. The governing Navier Stoke's equations are subjected to Penalty finite element method to eliminate pressure term and Galerkin weighted residual method is applied to obtain the solution of the reduced equations for different ranges of the physical parameters. The results are verified as grid independent and comparison is made as a limiting case with the results available in literature, and it is shown that the developed code is highly accurate. Computations are presented in terms of streamlines, isotherms, local Nusselt number and average Nusselt number through graphs and tables. It is observed that, for the case of uniform heating side walls, strength of circulation of streamlines gets increased when Rayleigh number is increased above critical value, but increase in Hartmann number decreases strength of streamlines circulations. For non-uniform heating case, it is noticed that heat transfer rate is maximum at corners of bottom wall.

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Unsteady Oscillatory Flow and Heat Transfer in a Horizontal Composite Porous Medium Channel

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2009.14.3.14503 ◽

2009 ◽

Vol 14 (3) ◽

pp. 397-415 ◽

Cited By ~ 33

Author(s):

J. C. Umavathi ◽

A. J. Chamkha ◽

A. Mateen ◽

A. Al-Mudhaf

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Oscillatory Flow ◽

Oscillation Amplitude ◽

Temperature Fields ◽

Thermal Conductivity Ratio ◽

Physical Parameters ◽

Conductivity Ratio ◽

Medium Parameter ◽

Flow And Heat Transfer

The problem of unsteady oscillatory flow and heat transfer in a horizontal composite porous medium is performed. The flow is modeled using the Darcy-Brinkman equation. The viscous and Darcian dissipation terms are also included in the energy equation. The partial differential equations governing the flow and heat transfer are solved analytically using two-term harmonic and non-harmonic functions in both regions of the channel. Effect of the physical parameters such as the porous medium parameter, ratio of viscosity, oscillation amplitude, conductivity ratio, Prandtl number and the Eckert number on the velocity and/or temperature fields are shown graphically. It is observed that both the velocity and temperature fields in the channel decrease as either of the porous medium parameter or the viscosity ratio increases while they increase with increases in the oscillation amplitude. Also, increasing the thermal conductivity ratio is found to suppress the temperature in both regions of the channel. The effects of the Prandtl and Eckert numbers are found to decrease the thermal state in the channel as well.

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