Energy Technology,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 12, 2024
Erythritol‐based
nanocapsules
with
a
phase‐change
temperature
of
120
°C
are
successfully
prepared
under
very
mild
conditions.
The
produced
via
multiple
crystallization
precipitations
from
saturated
erythritol
aqueous
solution,
followed
by
SiO
2
coating
using
sol–gel
method.
Their
nanostructure
and
elemental
composition
characterized
scanning
electron
microscopy
energy‐dispersive
X‐ray
spectroscopy.
latent
heat
the
is
measured
differential
calorimeter.
nanocapsules,
an
average
size
≈220
nm,
exhibit
melting
enthalpy
192.7
J
g
−1
.
Notably,
supercooling
degree
reduced
≈30.0
compared
to
pure
erythritol.
After
200
thermal
cycles,
storage
performance
shows
only
7.6%
decrease.
A
functional
fluid,
suitable
for
high‐temperature
transfer,
dispersing
in
silicone
oil.
conductivity
specific
capacity
this
fluid
increase
20.5%
283.3%,
respectively,
These
findings
demonstrate
that
significantly
enhance
properties
transfer
fluids,
highlighting
their
potential
application.
Energy,
Год журнала:
2024,
Номер
305, С. 132290 - 132290
Опубликована: Июль 2, 2024
Conversion
of
sunlight
to
heat
and
the
subsequent
thermal
storage
by
nanoencapsulated
bio-based
phase
change
material
slurries
(NBPCMSs)
in
a
low
temperature
solar
system
is
investigated.
The
influences
capsule
size,
shell
material,
tilt
angle,
flux,
PCM
mass
concentration,
nanoparticle
its
concentration
are
explored.
results
reveal
that
useful
gain
capacity
nano-enhanced
coconut
oil/Ag,
oil/Au,
oil/Al,
oil/Cu
based
respectively
3.02,
3.12,
2.7,
3.14
times
better
than
pure
water,
due
an
enhanced
interaction
light
with
functional
nanocapsules.
Consequently,
energy
reported
be
8.85,
9.29,
7.41,
9.19
higher.
increment
from
5
20
%
addition
blended
nanoparticles
further
augment
capacity.
Specifically,
oil/Au
slurry
improved
up
74.4
when
coconout
oil
used
as
core
material.
improvements
Cu
Ag
enhance
4.04
4.87
%,
respectively,
insertion
Au
at
volume
fraction
25
ppm.
Augmenting
core/shell
confinement
on
other
hand,
diminishes
surface
area
ratio,
allowing
agglomeration
structures
inside
slurry.
performance
decreases
inclination
angle
cavity
increases
0°
60°,
reducing
buoyancy
force
particles'
collision.
Further,
since
Al
particles
have
optical
characteristics
conductivity,
oil/Al
lowest
level.
Finally,
experiment
conducted
validate
specific
model
prediction
under
various
wind
speeds,
1
4
m/s,
illuminations,
400
1000
W/m2.
Journal of Molecular Liquids,
Год журнала:
2024,
Номер
411, С. 125702 - 125702
Опубликована: Авг. 5, 2024
The
photo-thermal
conversion
performance
(PTCP)
of
water-based
nanofluids
in
a
volumetrically
heated
solar
collector
(VHSC)
is
evaluated.
influences
nanoparticle
volume
concentration
(NVC),
particle
size,
Reynolds
number,
operating
temperature,
and
geometry
on
the
PTCP
are
numerically
investigated.
utilization
nanoparticles
improving
their
found
to
enhance
efficiency
(PTCE)
by
augmenting
energy
from
sun
working
fluid
due
radiation-nanoparticle
interactions.
PTCE
enhancement
Graphite,
TiO2
Ag
dispersed
water
respectively
1.37,
1.33
1.29
times
better,
compared
that
water.
This
further
augmented
adding
MgO
TiO2,
Graphite
particles,
resulting
1.69,
1.67
1.59x
improved
efficiency.
Enhancing
flow
rate
fluids
also
contributes
reducing
losses
thermal
ambient.
Besides,
enhanced
size
increases
overall
as
it
enables
nanofluid
absorb
more
energy.
length
accelerates
loss
ambient,
result
system
diminishes.
It
regarded
heat
absorption
declines
with
inlet
temperature
fluid.
Journal of Energy Storage,
Год журнала:
2024,
Номер
78, С. 110110 - 110110
Опубликована: Янв. 8, 2024
This
paper
investigates
the
photothermal
conversion
performance
of
an
innovative
heat
transfer
fluid
containing
nano-encapsulated
phase
chanage
material
(PCM)
with
metallic
shell
materials
in
a
solar
thermal
energy
storage
system.
The
influences
thickness,
core
size,
type,
PCM
mass
and
volume
concentrations
on
medium
are
investigated
compared.
results
show
that
rates
water-based
Ag,
Au,
Cu
Al
nanofluids
6.89,
5.86,
7.05
6.99
W,
respectively,
while
slurries
formed
by
adding
paraffin@Ag,
nano
capsules
to
pure
water
enhance
6.18,
13.38,
10.8
11.33
%,
respectively.
nanoparticle-based
further
augment
temperature
gains
enhancing
radiation
capture
capability
medium.
Specifically,
depending
concentration
PCM,
capacity
paraffin@Cu
slurry
is
augmented
up
290
%.
As
thickness
Ag
particles
also
decreases
from
8
2
nm,
it
augments
slurry's
ability
for
7
enhancement
dimensions
capsules,
however,
causes
surface
area-to-volume
ratio
(SA:V)
reduce
clustering.
Therefore,
behaviour
Paraffin@Cu
diminished
5
%
as
size
enhances
10
40
nm.
Further,
augmentation
surprisingly
reduces
Finally,
paraffin-based
solid
experimentally
tested
validation
specific
model
at
various
wind
speeds
radiation.
Journal of Molecular Liquids,
Год журнала:
2024,
Номер
400, С. 124567 - 124567
Опубликована: Март 24, 2024
Nanofluids
enhance
thermal
energy
transfer
in
storage
applications.
Proper
nanoparticles
are
crucial,
especially
regarding
their
thermophysical
properties.
This
work
fabricated
a
novel
instrument
to
evaluate
mixture
of
distilled
water-based
ternary
and
binary
nanofluids.
prepared
nanofluids
by
mixing
multi-wall
carbon
nanotubes
(MWCNTs),
magnesium
oxide
(MgO),
boron
nitride
(BN)
into
water
at
various
volume
concentrations.
The
that
has
been
measures
the
time
taken
reach
equilibrium
state
as
new
characteristic
compare
potential
nanofluids,
which
alleviates
dependence
on
other
instruments
occasionally
inaccessible
or
costly
for
researchers.
Thermodynamically,
this
enables
assessment
nano-energy,
manifested
heat
transferred
nanofluid
while
reaching
an
state.
results
verified
purpose
proposed
instrument;
was
affected
perfectly
increasing
concentration
base
fluid.
All
with
0.5
%
emerged
most
effective
achieving
shorter
than
hybrid
MWCNTs–MgO–BN
had
shortest
time,
157
s.
8.3,
5.8,
11.8
more
MWCNTs–MgO,
MWCNTs–BN,
MgO–BN
essence
behind
result
obtained
created
lies
fact
it
generated
approach
evaluating
thanks
possible
find
out
fluid
highest
conductivity.
uncertainty
analysis
showed
error
acceptability
experimental
instrument,
average
value
percentage
all
presented
composites
±
0.936
%.
