Manish K. Khandelwal and P. Bera and A. Chakrabarti Effect of Buoyancy Ratio on NonDarcy Mixed Convection in a Vertical Channel A Thermal Nonequilibrium Approach
1046 - 1050
2012
6
8
International Journal of Physical and Mathematical Sciences http://waset.org/publications/8046
http://waset.org/publications/68
World Academy of Science, Engineering and Technology
This article presents a numerical study of the doublediffusive
mixed convection in a vertical channel filled with porous
medium by using nonequilibrium model. The flow is assumed
fully developed, unidirectional and steady state. The controlling
parameters are thermal Rayleigh number (RaT ), Darcy number (Da),
Forchheimer number (F), buoyancy ratio (N), inter phase heat transfer
coefficient (H), and porosity scaled thermal conductivity ratio
(γ). The Brinkmanextended nonDarcy model is considered. The
governing equations are solved by spectral collocation method. The
main emphasize is given on flow profiles as well as heat and solute
transfer rates, when two diffusive components in terms of buoyancy
ratio are in favor (against) of each other and solid matrix and fluid
are thermally nonequilibrium. The results show that, for aiding flow
(RaT 1000), the heat transfer rate of fluid (Nuf ) increases upto a
certain value of H, beyond that decreases smoothly and converges
to a constant, whereas in case of opposing flow (RaT 1000),
the result is same for N 0 and 1. The variation of Nuf in (N,
Nuf )plane shows sinusoidal pattern for RaT 1000. For both cases
(aiding and opposing) the flow destabilize on increasing N by inviting
point of inflection or flow separation on the velocity profile. Overall,
the buoyancy force have significant impact on the nonDarcy mixed
convection under LTNE conditions.
International Science Index 68, 2012