Abstract
In this paper we investigate the complete behavior of the viscous and incompressible fluid flow in an anisotropic saturated porous horizontal cavity. Taking into account the rigid/rigid and stress-free/stress-free horizontal boundaries, we obtain the exact solutions for flow and heat transfer equations, i.e. the velocity and temperature, depending on the Darcy–Rayleigh number, the Darcy number, the anisotropic permeability ratio and the inclination of the principal axis. These obtained variables allow us to compute the different expressions of the pressure gradient.
Similar content being viewed by others
Abbreviations
- \(a, b, c\) :
-
Constants
- \(C\) :
-
Dimensionless temperature gradient in \(x\) direction
- \(Da\) :
-
Darcy number, \(K_1/{L'}^{2}\)
- \(\overrightarrow{g}\) :
-
Gravitational acceleration
- \(H'\) :
-
Depth of cavity
- \(k\) :
-
Thermal conductivity
- \(\overline{K}\) :
-
Flow permeability tensor
- \(K_1, K_2\) :
-
Flow permeability along the principal axes
- \(K^{\star }\) :
-
Anisotropic permeability ratio, \(K_1/K_2\)
- \(L'\) :
-
Width of cavity
- \(q'\) :
-
Uniform heat flux
- \(Ra\) :
-
Darcy–Rayleigh number, \(g\beta K_1{L'}^2q'/k\nu \alpha \)
- \(Ra^{\star }\) :
-
Rayleigh number for a fluid, \(Ra/Da\)
- \(t\) :
-
Dimensionless time
- \(\widetilde{T}\) :
-
Dimensionless temperature
- \(T\) :
-
Dimensionless quasi-state temperature, \(\widetilde{T}-\xi t\)
- \(\Delta T'\) :
-
Temperature scale, \(q'L'/k\)
- \(\Delta T\) :
-
Wall to wall dimensionless temperature difference at \(x=0\)
- \(\overrightarrow{V}\) :
-
Seepage velocity
- \(u, v\) :
-
Dimensionless velocity components in \(x, y\) directions
- \(x\) :
-
Dimensionless horizontal coordinate
- \(y\) :
-
Dimensionless vertical coordinate Greek symbols
- \(\alpha \) :
-
Thermal diffusivity
- \(\beta \) :
-
Thermal expansion coefficient of the fluid
- \(\gamma \) :
-
Inclination of the principal axis
- \(\mu \) :
-
Dynamic viscosity of the fluid
- \(\nu \) :
-
Kinematic viscosity of the fluid
- \(\phi \) :
-
\(y\)-Dependent temperature term
- \(\psi \) :
-
Dimensionless stream function, \(\psi '/\alpha \)
- \(\rho \) :
-
Density of the fluid
- \((\rho c)_f\) :
-
Heat capacity of the fluid
- \((\rho c)_p\) :
-
Heat capacity of saturated porous medium
- \(\tau \) :
-
Dimensionless Darcy parameter, \({Da}^{-\frac{1}{2}}\)
- \(\sigma \) :
-
Heat capacity ratio, \((\rho c)_p/(\rho c)_f\)
- \(\xi \) :
-
Dimensionless uniform heat sink Superscript
- \('\) :
-
Dimensional quantities Subscript
- \(o\) :
-
Refers to origin
References
Bear, J.: Dynamics of Fluids in Porous Media. Dover Publication, Elsevier, New York (1972)
Bejan, A.: Convection Heat Transfer. Wiley, New York (1984)
Eglit, M.E.: Problems in Mechanical Theory of Continua. Moscow Lycee, Moscow(1996)
Weber, J.E.: Convection in a porous medium with horizontal and vertical temperature gradients. Int. J. Heat Mass Transfer 17, 241–248 (1974)
Nield, D.A.: Convection in a porous medium with inclined temperature gradients. Int. J. Heat Mass Transfer 34, 87–92 (1991)
Walker, K.L., Homsy, G.M.: A note of convective instability in Boussinesq fluids and porous media. J. Heat transfer 99, 338–339 (1977)
Vasseur, P., Robillard, L.: The Brinkman model in a porous layer: effects of nonuniform thermal gradient. Int. J. Heat Mass Transfer 36, 4199–4206 (1993)
Mckibbin, R.: Thermal convection in a porous layer: effects of anisotropy and surface boundary conditions. Trans. Porous Media 1, 271–292 (1984)
Degan, G., Vasseur, P.: Influence of anisotropy on convection in porous media with nonuniform thermal gradient. Int. J. Heat Mass Transfer 46, 781–789 (2003)
Lu, L., Doering, C.R., Busse, F.H.: Bounds on convection driven by internal heating. J. Math. Phys. 45(7), 2968–2985 (2004)
Castinel, G., Combarnous, M.: Critère d’apparition de la convection naturelle dans une couche poreuse anisotrope. J.C.R. Hebd. Seanc. Acad. Sci. Paris B278, 701–704 (1974)
Degan, G., Vasseur, P.: Boundary layer regime in a vertical porous layer with anisotropic permeability and boundary effects. Int. J. Heat Fluid Flow 18, 334–343 (1997)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Adanhounme, V., Olodo, E.T. Exact solutions for equations of flow and heat transfer in fluid saturated porous media. Afr. Mat. 26, 913–921 (2015). https://doi.org/10.1007/s13370-014-0258-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s13370-014-0258-7