Case Studies in Thermal Engineering,
Год журнала:
2024,
Номер
61, С. 104887 - 104887
Опубликована: Июль 27, 2024
This
work
aims
to
investigate
the
vibration
behavior
of
porous
three-directional
functionally
graded
(3D-FG)
microshells
in
thermal
environments,
where
both
mechanical
and
material
properties
vary
along
three
spatial
directions
following
a
power-law
distribution,
based
on
modified
couple
stress
theory
(MCST).
An
isoparametric
element
is
employed
for
uncoupled
heat
conduction
analysis,
followed
by
dynamic
analysis
using
penalty
solid
with
translation
degrees
freedom
(DOFs)
rotation
DOFs
per
node.
However,
due
strong
nonlinearity
temperature
field
3D-FG
microshells,
obtaining
exact
values
at
integration
points
requires
pretty
dense
mesh
element.
To
overcome
this
issue,
back
propagation
(BP)
neural
network
utilized
predict
various
gradient
indexes,
enhancing
efficiency
precision
distribution
calculation.
Numerical
results
demonstrate
effectiveness
enhanced
finite
model.
Furthermore,
effects
length
scale
parameter
(MLSP),
difference,
indexes
natural
frequencies
are
investigated.
It
shown
that
higher
structural
stiffness
weakens
impact
difference
frequency.
Technologies,
Год журнала:
2023,
Номер
11(2), С. 35 - 35
Опубликована: Фев. 24, 2023
In
this
work,
a
coupled
3D
thermo-elastic
shell
model
is
presented.
The
primary
variables
are
the
scalar
sovra-temperature
and
displacement
vector.
This
allows
for
thermal
stress
analysis
of
one-layered
sandwich
plates
shells
embedding
Functionally
Graded
Material
(FGM)
layers.
equilibrium
equations
Fourier
heat
conduction
equation
spherical
put
together
into
set
four
equations.
They
automatically
degenerate
in
those
simpler
geometries
thanks
to
proper
considerations
about
radii
curvature
use
orthogonal
mixed
curvilinear
coordinates
α,
β,
z.
obtained
partial
differential
governing
along
thickness
direction
solved
using
exponential
matrix
method.
closed
form
solution
possible
assuming
simply
supported
boundary
conditions
harmonic
forms
all
unknowns.
amplitudes
directly
imposed
at
outer
surfaces
each
geometry
steady-state
conditions.
effects
environment
related
profiles
through
thickness.
static
responses
evaluated
terms
displacements
stresses.
After
global
preliminary
validation,
new
cases
presented
different
ratios,
geometries,
temperature
values
external
surfaces.
considered
FGM
metallic
bottom
ceramic
top.
layer
can
be
embedded
configuration
or
configuration.
fully
provides
results
that
coincident
with
proposed
by
uncoupled
separately
solves
equation.
differences
always
less
than
0.5%
investigated
displacement,
temperature,
component.
between
present
full
advantages
clearly
shown.
Both
material
included
conducted
analyses.
Waves in Random and Complex Media,
Год журнала:
2023,
Номер
unknown, С. 1 - 27
Опубликована: Янв. 25, 2023
This
paper
studies
the
free
vibration
of
size-dependent
functionally
graded
material
(FGM)
microplates
in
contact
with
viscous
fluid.
The
Mori-Tanaka
model
is
applied
to
formulate
continuous
gradual
variation
properties
FGM
along
thickness
direction.
A
non-classical
microplate
established
based
on
modified
couple
stress
theory,
which
considers
size
effect
by
introducing
length
scale
parameter.
physical
neutral
plane
introduced
eliminate
stretching-bending
coupling
effect.
motion
fluid
defined
Navier-Stokes
equations,
hydrodynamic
loading
determined
consideration
inertial
and
damping
governing
equations
for
are
derived
using
Hamilton’s
principle
solved
differential
quadrature
method.
Numerical
results
obtained
discuss
influences
aspect
ratio,
depth,
slenderness
viscosity,
gradient
index,
density,
parameter
behaviors
