Analysis of a Double Pipe Heat Exchanger Performance by Use of Porous Baffles and Nanofluids
The present work is a numerical simulation of
nanofluids flow in a double pipe heat exchanger provided with
porous baffles. The hot nanofluid flows in the inner cylinder, whereas
the cold nanofluid circulates in the annular gap. The Darcy-
Brinkman-Forchheimer model is adopted to describe the flow in the
porous regions, and the governing equations with the appropriate
boundary conditions are solved by the finite volume method. The
results reveal that the addition of metallic nanoparticles enhances the
rate of heat transfer in comparison to conventional fluids but this
augmentation is accompanied by an increase in pressure drop. The
highest heat exchanger performances are obtained when
nanoparticles are added only to the cold fluid.
Double pipe heat exchanger, Nanofluids,
Nanoparticles, Porous baffles.
MHD Mixed Convection in a Vertical Porous Channel
This work deals with the problem of MHD mixed
convection in a completely porous and differentially heated vertical
channel. The model of Darcy-Brinkman-Forchheimer with the
Boussinesq approximation is adopted and the governing equations are
solved by the finite volume method. The effects of magnetic field and
buoyancy force intensities are given by the Hartmann and Richardson
numbers respectively, as well as the Joule heating represented by
Eckert number on the velocity and temperature fields, are examined.
The main results show an augmentation of heat transfer rate with the
decrease of Darcy number and the increase of Ri and Ha when Joule
heating is neglected.
Heat sources, magnetic field, mixed convection,
Heat and Mass Transfer of an Oscillating Flow in a Porous Channel with Chemical Reaction
A numerical study is made in a parallel-plate porous
channel subjected to an oscillating flow and an exothermic chemical
reaction on its walls. The flow field in the porous region is modeled
by the Darcy–Brinkman–Forchheimer model and the finite volume
method is used to solve the governing equations. The effects of the
modified Frank-Kamenetskii (FKm) and Damköhler (Dm) numbers,
the amplitude of oscillation (A), and the Strouhal number (St) are
examined. The main results show an increase of heat and mass
transfer rates with A and St, and their decrease with FKm and Dm.
Chemical reaction, heat transfer, mass transfer,
oscillating flow, porous channel.