Physics of Fluids,
Journal Year:
2024,
Volume and Issue:
36(12)
Published: Dec. 1, 2024
Microfractures
are
ubiquitous
in
subsurface
porous
media
due
to
natural
and
engineering
activities.
Imbibition
fractured
affects
various
geological
applications,
while
their
behaviors
have
not
been
sufficiently
understood.
This
study
conducts
spontaneous
forced
imbibition
experiments
at
capillary
numbers
micromodels
with
different
fracture
apertures.
Air
mixtures
of
glycerol
ethanol
the
non-wetting
wetting
fluids,
respectively.
Results
identify
two
patterns:
matrix-preferential
fracture-preferential.
A
global
number
is
insufficient
predict
flow
patterns
media.
Pore-scale
interfacial
influence
by
affecting
crossflow
between
matrix.
The
concave-to-convex
transition
meniscus
found
pore
invasion
introduces
a
transient
resistance
inhibiting
into
Cooperative
fillings
weaken
promote
imbibition.
from
front
matrix
driven
pressure
prefers
low
numbers.
higher
increases
viscous
limits
crossflow,
which
promotes
matrix-
fracture-preferential
rise
concentration
viscosity
contact
angle.
These
features
increase
for
facilitate
wider-fracture
aperture
enhances
capillary-dominant
increasing
difference,
it
also
has
lower
causes
an
early
large
relevant
prediction
simulation
Physics of Fluids,
Journal Year:
2025,
Volume and Issue:
37(2)
Published: Feb. 1, 2025
The
challenges
of
constraints
and
imprecision
in
chemical
analysis
medical
diagnosis
are
particularly
evident
the
separation
blood
cells.
Pinched
flow
fractionation,
a
passive
microfluidic
technique,
has
gained
attention
for
its
potential
size-based
cell
separation.
Enhancing
efficiency
is
crucial,
especially
through
integration
with
external
forces
or
active
methods.
This
study
explores
use
dielectrophoresis
(DEP)
magnetophoresis
(MP)
to
separate
platelet
cells,
red
white
circulating
tumor
These
were
analyzed
both
independently
simultaneously.
To
achieve
optimal
separation,
Navier–Stokes
equations,
Newton's
second
law,
system's
electric
magnetic
fields
modeled.
Experiments
conducted
branched
microchannel
assess
impact
various
parameters,
including
buffer
rate,
pinched
section
width,
applied
voltage,
field
frequency,
intensity.
revealed
approximately
99%
under
conditions
Wp=20
μm,
Q2=1250
μl/h,
f=100
kHz,
V=3
V,
M=1.5
T.
findings
demonstrate
that
while
DEP
MP
individually
enhance
their
simultaneous
application
significantly
improves
precision,
achieving
complete
optimized
system
holds
great
promise
applications
analytical
chemistry
diagnostics,
analysis.
Physics of Fluids,
Journal Year:
2024,
Volume and Issue:
36(7)
Published: July 1, 2024
This
study
explores
electroosmotic
mixing
in
microfluidic
channel
with
predefined
surface
topology,
mainly
focusing
the
effect
of
charge-dependent
slip
length
on
underlying
dynamics.
Our
analysis
addresses
need
for
precise
control
flow
and
participating
fluids
at
microscale,
crucial
medical
biomedical
applications.
In
present
work,
we
consider
a
wavy
microchannel
non-uniform
charge
to
explore
behavior.
To
this
end,
adopting
finite-element
approach,
numerically
solve
Laplace,
Poisson–Boltzmann,
convection–diffusion,
Navier–Stokes
equations
steady-state.
The
model
is
validated
by
comparing
results
available
theoretical
experimental
data.
Through
numerical
simulations,
analyzes
patterns
microchannels,
highlighting
impact
lengths
efficiency.
For
example,
diffusive
Peclet
number
200,
efficiency
drops
from
95.5%
91.5%
when
considering
length.
It
established
that
fluid
rheology,
characterized
Carreau
behavior
index,
non-trivially
influences
field
modulation
Increased
numbers
enhance
velocity,
affecting
overall
constituent
chosen
fluidic
pathway.
instance,
increasing
0.01
1.0,
discernible
trend
emerges
higher
line
density
accelerated
velocity
within
microchannel.
also
examines
efficiency,
particularly
convective
regime
transport.
These
insights
offer
practical
guidance
designing
systems
intended
enhanced
capabilities.
Additionally,
likelihood
particle
aggregation
under
shear
forces,
vital
biological
non-Newtonian
fluids,
implications
drug
delivery,
diagnostics,
technologies.
Scientific Reports,
Journal Year:
2024,
Volume and Issue:
14(1)
Published: Aug. 8, 2024
Abstract
The
PNP
nanotransistor,
consisting
of
emitter,
base,
and
collector
regions,
exhibits
distinct
behavior
based
on
surface
charge
densities
various
electrolyte
concentrations.
In
this
study,
we
investigated
the
impact
density
ion
transport
within
nanotransistors
at
different
concentrations
applied
voltages.
We
employed
a
finite-element
method
to
obtain
steady-state
solutions
for
Poisson–Nernst-Planck
Navier–Stokes
equations.
ions
form
depletion
region,
influencing
ionic
current,
analyze
influence
depth
region.
Our
findings
demonstrate
that
an
increase
in
results
deeper
zone,
leading
reduction
current.
However,
very
low
concentrations,
optimal
causes
current
reach
its
lowest
value,
subsequently
increasing
with
further
increments
density.
As
such,
$${V}_{app}=+1
\text{V}$$
Vapp=+1V
$${C}_{0}=1
\text{mM}$$
C0mM
,
increases
by
25%
when
rises
from
5
20
$$\text{mC}.{\text{m}}^{-2}$$
mC.m-2
whereas
$${C}_{0}=10
10
decreases
65%
same
This
study
provides
valuable
insights
into
their
potential
applications
nanoelectronic
devices.
Physics of Fluids,
Journal Year:
2024,
Volume and Issue:
36(11)
Published: Nov. 1, 2024
Soft
bipolar
nanochannels
provide
distinct
and
valuable
understanding
of
the
intricate
relationship
among
shape,
charge
distribution,
concentration,
flow
dynamics.
This
study
investigates
intriguing
realm
nanoscale
structures,
where
two
configurations
soft
layers
with
varying
charges
an
but
appealing
setting
for
movement
management
ions,
as
well
regulation
control
ionic
species
in
five
various
geometries.
It
generates
cylindrical,
trumpet,
dumbbell,
hourglass,
conical
forms.
The
are
coated
a
diffuse
polyelectrolyte
layer,
density
distribution
layer
is
described
using
step
function.
To
enhance
accuracy,
impact
partitioning
taken
into
account.
investigate
effect
polarity,
types
were
considered:
Type
I
II.
In
I,
negative
pole
at
start,
while
II,
positive
start.
Thus,
features
arrangement
negative–positive
(NP),
whereas
II
has
positive–negative
(PN)
configuration.
research
was
conducted
under
stationary
conditions
finite
element
method,
Poisson–Nernst–Planck,
Navier–Stokes
equations.
By
manipulating
variables
such
order,
bulk
numerical
analysis
performed
to
these
on
current–voltage
parameters.
results
demonstrate
serves
more
effective
receiver
generating
greater
rectification.
For
instance,
dumbbell-shaped
nanochannel
exhibits
rectification
2046
concentration
1
mM
lowest
layer.
From
alternative
perspective,
conductivity
significantly
influenced
by
concentration.
study's
findings
fundamental
principles
have
profound
implications
diverse
applications
nanochannels.
capacity
regulate
manipulate
ion
transport
through
can
result
enhanced
efficiency,
selectivity,
performance
processes.
Soft Matter,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 1, 2025
The
present
article
deals
with
the
modulation
of
oscillatory
electroosmotic
flow
(EOF)
and
solute
dispersion
across
a
nanochannel
filled
an
electrolyte
solution
surrounded
by
layer
dielectric
liquid.
Physics of Fluids,
Journal Year:
2025,
Volume and Issue:
37(2)
Published: Feb. 1, 2025
Rough
fractures
with
geometric
heterogeneity
significantly
affect
the
movement
characteristic
of
gas–water
flow
interface.
However,
studies
on
in
smooth
or
reconstructed
face
challenges
clarifying
specific
effect
fracture
roughness
microflow.
This
study
employs
Weierstrass–Mandelbrot
function
to
model
rough
and
develops
a
theoretical
for
interface
by
coupling
Navier–Stokes
phase-field
equations.
provides
robust
framework
analyzing
microflow
is
validated
through
contact
angle
measurements
coal,
shale,
sandstone,
salt
rock.
The
investigates
microscopic
characteristics
gas
water
single
networks.
simulation
results
show
that
accumulates
asperities
fractures,
its
residual
volume
fraction
increasing
fractal
dimension
but
decreasing
larger
angles.
vortices
within
are
fundamental
reason
preventing
transport
water.
As
increases,
both
breakthrough
time
increase,
indicating
greater
reduces
speed
limits
effective
space.
Additionally,
four
typical
distribution
patterns
(H-channel,
parallel
channel,
dead-end
asperities)
identified.
offers
critical
insights
into
how
influences
microflow,
potentially
guiding
improved
energy
recovery
storage
strategies
fractured
formation.
