Abstract
The problem of combined convection from vertical surfaces in a porous medium saturated with a power-law type non-Newtonian fluid is investigated. The transformed conservation laws are solved numerically for the case of variable surface heat flux conditions. Results for the details of the velocity and temperature fields as well as the Nusselt number have been presented. The viscosity index ranged from 0.5 to 2.0.
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Abbreviations
- d :
-
particle diameter (m)
- f :
-
dimensionless stream function
- g :
-
acceleration due to gravity (m/s2)
- h :
-
heat transfer coefficient (W/m2 K)
- k :
-
thermal conductivity (W/mK)
- K :
-
permeability coefficient of the porous medium (m1+n)
- m :
-
consistency index for power-law fluid (pa sn)
- n :
-
viscosity index
- Nu:
-
Nusselt number
- Pe:
-
Péclet number
- qw :
-
wall heat flux (W/m2)
- Ra* :
-
modified Rayleigh number
- T :
-
temperature (K)
- u, v :
-
velocity components in x and y directions (m/s)
- x, y :
-
axial and normal coordinates (m)
- α:
-
thermal diffusivity (m2/s)
- β :
-
coefficient of thermal expansion (1/K)
- η:
-
dimensionless distance
- Θ:
-
dimensionless temperature
- ϱ :
-
density (kg/m3)
- ɛ :
-
porosity
- χ :
-
combined convection nonsimilar parameter
- ψ :
-
stream function
- ω :
-
surface conditions
- ∞:
-
conditions far away from the surface
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Kumari, M., Reddy Gorla, R.S. Combined convection in power-law fluids along a nonisothermal vertical plate in a porous medium. Transp Porous Med 24, 157–166 (1996). https://doi.org/10.1007/BF00139843
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DOI: https://doi.org/10.1007/BF00139843