Case Studies in Thermal Engineering,
Год журнала:
2024,
Номер
56, С. 104250 - 104250
Опубликована: Март 15, 2024
This
article
aims
to
improve
the
convection
flow
within
a
two-dimensional
chamber
by
utilizing
nano-encapsulated
phase
change
material
(NEPCM).
The
center
contains
flame-shaped
heating
source,
and
bottom
wall
is
wavy.
Forced
occurs
due
motion
of
chamber's
side
walls,
while
natural
arises
from
thermal
gradient
across
walls.
Galerkin-finite
element
GFEM
approach
was
employed
analyze
system's
governing
equations.
study
investigates
impact
following
factors
on
heat
transfer:
velocity
(Re
=
10–1000),
movement
directions
(both
walls
moving
in
positive
direction,
both
negative
one
other
positive),
intensity
magnetic
field
(Ha
0–100),
cavity
porosity
(Da
10−5
–
10−2).
results
demonstrate
that
increasing
Re
Da
improves
average
Nusselt
number
(NuAvg).
Conversely,
raising
opposite
direction
reduces
NuAvg.
At
1000,
(10−2
instead
10−5)
leads
139%
increase
NuAvg,
decreasing
Ha
same
NuAvg
11.5%
640%,
respectively.
International Journal of Thermofluids,
Год журнала:
2023,
Номер
20, С. 100463 - 100463
Опубликована: Сен. 16, 2023
In
this
study,
entropy
accumulation
during
thermal
convection
of
a
hybrid
nanosuspension
in
an
undulating
cavity
having
interior
heated
plate
is
investigated
relation
to
magnetic
fields.
The
Darcy-Brinkman-Forchheimer
approach
employed
simulate
the
liquid
circulation
and
energy
transport
parameters,
while
impact
Lorentz
force
on
system's
thermodynamic
properties
analyzed.
To
better
understand
characteristics
complex
phenomenon,
best
compromise
combination
different
interacted
parameters
needed
be
set
on.
geometrical
are
number
waves
(N),
length
(s)
inclination
angle
(γ)
(δ).
These
studied
with
volume
fractions
compound
nanofluid
(φ
=
0
−
−0.02),
Rayleigh
numbers
(103
−106),
Darcy
changes
between
(Da
10−5
−10−1)
various
Hartmann
(Ha
−60).
mean
Nusselt
rises
growth
by
about
three
times
(≈300%),
average
skin
friction
parameter
reduces
wall
approximately
half
(≈50%).
Additionally,
Bejan
reaches
its
maximum
value
when
equals
(N
5).
Taking
into
consideration
objective
function
maximizing
Nu
minimizing
frication
coefficient
(Cf),
scenario
determined
at
3,
s
0.4,
γ
π/3
δ
π/2).
Case Studies in Thermal Engineering,
Год журнала:
2023,
Номер
43, С. 102788 - 102788
Опубликована: Фев. 3, 2023
Fins
are
utilized
in
a
variety
of
technical
applications
such
as
heat
exchangers,
electrical
transformers,
semiconductors,
air-cooled
engines,
gas
turbines,
automotive
radiators,
hydrogen
fuel
cells,
and
so
on.
Nanofluids
innovative
designed
fluids
with
improved
thermal
conductivity
comparison
to
standard
coolants.
The
nanofluids
more
efficient
well
repudiated
transportation
evaluated
regular
due
nanoparticle
presence
the
base
medium.
efficiency
nanofluid
is
nanoparticles.
With
this
motivation,
objective
present
article
analyze
hydrothermal
analysis
MgO−water
flow
across
hexagonal
cavity
inner
circular
cylinder.
inside
cylinder
fitted
various
rectangular
fins.
upper
bottom
wall
heated
while
other
alls
cold.
dimensional
equations
transmuted
into
non-dimensional
system
by
using
suitable
similarity
alternation.
tackled
utilizing
Galerkin
finite
element
method
computational
COMSOL
Multiphysics
software.
Different
streamlines
isotherms
Nusselt
number
profile
plots
for
significance
Rayleigh
(Ra),
Hartmann
(Ha)
volume
fraction
(Φ)
different
fins
length
flow.
From
results,
it
observed
that
convection,
velocity
outcomes
boosted
up
number.
components
reduces
via
increment
nanoparticles
concentration.
Furthermore,
reveals
reduced
local
inverse
trend
noted
fraction.
Case Studies in Thermal Engineering,
Год журнала:
2024,
Номер
54, С. 103992 - 103992
Опубликована: Янв. 10, 2024
Maximizing
heat
transfer
rates
within
enclosed
cavities
is
of
paramount
importance
in
various
engineering
applications.
This
study
focuses
on
enhancing
transmission
efficiency
through
forced
convection
a
triangular
cavity
containing
rotating
cylinder.
The
approach
involves
incorporating
Nano-Encapsulated
Phase
Change
Material
(NEPCM),
applying
uniform
magnetic
field,
and
introducing
cold,
dynamically
cavity's
configuration
maintains
an
elevated
temperature
the
upper
wall
while
inclined
side
walls
remain
cold.
investigation
also
explores
impact
varying
position
cylinder
cavity.
Mathematical
modeling
undertaken
using
Galerkin
finite
element
methodology.
Numerical
results
reveal
direct
proportionality
between
Nusselt
number
(Nu)
Darcy
(Da),
as
well
inverse
Nu
Hartmann
(Ha).
Elevating
from
10−5
to
10−2
leads
54%
increase
number,
increasing
0
100
12.5%
decrease
Nu.
Intriguingly,
positioning
cold
enclosure
240%
enhancement
highlights
intricate
interplay
geometry
external
fields
optimizing
complex
cavities.
Case Studies in Thermal Engineering,
Год журнала:
2023,
Номер
47, С. 103072 - 103072
Опубликована: Май 20, 2023
Using
the
potential
of
nature's
phenomena
such
as
free
convection
phenomenon
could
help
to
cooling
a
piece,
moving
hot
plate
in
lid-driven
problems.
Moreover,
adding
modern
nanostructures
named
nano-encapsulated
phase
change
material
(NEPCM)
with
ability
transition
greatly
improve
heat
transfer
processes.
In
this
study,
mixed
ethylene
glycol
(EG)
and
NEPCM
was
simulated
inside
cavity
rotating
cylinder
evaluate
contribution
Grashof
number,
speed,
concentration
on
characteristics.
Hence,
findings
current
numerical
study
indicated
that
6%
increased
mean
Nusselt
number
by
41.7%.
speed
enhanced
38.7%.
Finally,
there
an
optimum
value
for
occurred
4%
brought
104.
