Transport in Porous Media

, Volume 24, Issue 2, pp 157–166

Combined convection in power-law fluids along a nonisothermal vertical plate in a porous medium

  • Mahesh Kumari
  • Rama Subba Reddy Gorla
Article

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.

Key words

non-Newtonian fluids combined convection heat transfer 

Nomenclatures

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

Subscripts

ω

surface conditions

conditions far away from the surface

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References

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Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • Mahesh Kumari
    • 1
  • Rama Subba Reddy Gorla
    • 2
  1. 1.Department of MathematicsIndian Institute of ScienceBangaloreIndia
  2. 2.Mechanical Engineering DepartmentCleveland State UniversityClevelandUSA

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