Computational
Fluid
Dynamics
coupled
with
Discrete
Element
Method
(CFD-DEM)
has
been
extensively
utilized
for
studying
hydrodynamics
and
heat
transfer
in
fluidization
processes.
This
study
specifically
focuses
on
improving
a
biomass
fluidized
bed
combustor
immersed
tubes.
The
investigation
involves
the
use
of
mixed
biomass,
exploring
effects
types,
loading,
blending
ratios
to
propose
criteria
selecting
suitable
fuel
system.
Design
parameters
related
tubes,
such
as
angle
between
tube
diameters,
distance
were
also
considered.
A
data-driven
model
was
developed
based
CFD-DEM
results
predict
system
parameters.
offers
potential
applications
real-time
practical
engineering
without
need
simulation.
cylindrical
spherical
silica
sand
particles,
incorporating
an
appropriate
drag
force
model.
showed
that
ratio
1:3
wood
chips
coarse
bagasse,
5%
loading
using
average
equivalent
diameter
biomasses
4.44,
identified
conditions
general
case
obtain
most
efficient
hydrodynamic
this
study.
are
greater
than
sand.
Additionally,
proportion
should
be
less
bagasse.
Furthermore,
through
2k
factorial
design
analysis,
it
determined
tubes
had
significant
influence
behaviors.
Moreover,
development
Artificial
Neural
Network
(ANN)
models
successful
simulation
dataset,
enabling
accurate
predictions
mixing
index,
solid
volume
fraction,
temperature
within
enhances
understanding
systems
provides
valuable
insights
optimizing
operation
involving
Powder Technology,
Год журнала:
2023,
Номер
427, С. 118707 - 118707
Опубликована: Июнь 8, 2023
Physical
experiments
and
discrete
element
model
(DEM)
simulations
are
conducted
to
evaluate
particle
characteristics
operation
parameter
effects
on
screw
feeding
performance
for
rotary
shear-milled
Douglas
fir.
Three
metrics
used:
mass
flow
rate,
shaft
driving
torque,
specific
energy
consumption.
The
impact
of
size,
size
distribution
(PSD),
rotational
speed
(rpm),
hopper
dimensions
the
investigated.
All
employed
reveal
superior
flowability
2-mm
particles
in
contrast
larger
6-mm
counterpart.
Remarkably,
wider
PSD
results
poorer
than
two
mono-sized
particles,
proving
enhancement
achieved
by
narrower
woody
feedstock.
More
importantly,
DEM
unveil
PSD-induced
degradation
is
attributed
mechanical
interlocking
segregation
effects.
Furthermore,
higher
rpm
causes
rate
at
cost
consumption
due
viscous
dissipation
changes
pattern.
Frontiers in Energy Research,
Год журнала:
2022,
Номер
10
Опубликована: Май 5, 2022
Biomass
has
potential
as
a
carbon-neutral
alternative
to
petroleum
for
chemical
and
energy
products.
However,
complete
replacement
of
fossil
fuel
is
contingent
upon
efficient
processes
eliminate
undesirable
characteristics
biomass,
e.g.,
low
bulk
density,
variability,
storage-induced
quality
problems.
Mechanical
size
reduction
via
comminution
processing
operation
engineer
favorable
biomass
flowability
in
handling.
Crumbler
rotary
shear
mill
been
empirically
demonstrated
produce
more
uniformly
shaped
particles
with
higher
than
hammermilled
biomass.
This
study
combines
modeling
experimentation
unveil
fundamental
understandings
the
relation
between
granular
particle
flow
behavior,
which
elucidate
underlying
mechanisms
guide
selection
critical
parameters.
For
this
purpose,
impact
material
attributes,
including
(2–6
mm),
shape
(briquette,
chip,
clumped-sphere,
cube,
etc.),
surface
roughness,
on
angle
repose
(AOR)
milled
pine
chips
were
investigated
using
discrete
element
method
(DEM)
simulations.
Forest
Concepts
system
used
within
same
range
considered
DEM
AOR
different
sets
these
measured
experimentally
benchmark
results
against
experimental
data.
Specific
consumption
moisture
content
are
technoeconomic
analysis.
Our
show
that
smaller
(2
mm)
achieves
better
followability
(i.e.,
AOR)
while
cost
significantly
density
almost
6-mm
particles.
2-mm
size,
Crumbles
from
veneer
have
properties
chips.
Contrarily,
no
significant
difference
was
observed
two
materials
size.
Furthermore,
simulations,
mechanical
interlocking
found
dominant
factor
determining
complex-shaped
such
pine,
cannot
be
accurately
captured
by
simple
shapes
(e.g.,
mono-sphere)
rolling
resistance
model.
Conversely,
clumped-sphere
model
alleviates
limitation
without
increasing
computational
can
accurate
representation
when
simulating
free-flow
behavior.
Powder Technology,
Год журнала:
2024,
Номер
440, С. 119771 - 119771
Опубликована: Апрель 17, 2024
An
experiment-informed
discrete
particle
simulation
study
was
performed
to
investigate
the
role
of
flexural
particles
in
shear
flow
milled
pine
residues.
Physical
anatomical
fraction
samples
were
tested
an
FT4
powder
rheometer.
A
chip
model
for
bark/stem
chips
and
a
fiber
needles
proposed
DEM.
The
simulations
show
mixed
fibers/chips
require
higher
force
torque
drive
than
pure
or
fibers.
mass
flexibility
fibers
reveal
nonlinear
inter-dependency
on
impacting
fibers/chips.
Polydisperse
well
match
needle-rich
attributes,
while
polydisperse
agree
reasonably
with
bark/stem-rich
samples.
DEM
indicates
that
flowability
residue
biomass
is
determined
collectively
by
various
material
attributes
fractions,
which
must
be
considered
when
developing
preprocessing
methods
conversion-ready
adequate
handling
performance.
Fuel,
Год журнала:
2024,
Номер
375, С. 132572 - 132572
Опубликована: Июль 31, 2024
This
study
investigates
the
intricate
relationship
between
biomass
preprocessing
and
pyrolysis
product
yields,
employing
air
classification
technique
for
treatment
of
loblolly
pine
residues
with
varying
moisture
content.
A
comprehensive
exploration
physicochemical
properties
air-classified
informs
a
sophisticated
simulation
model.
Given
complex
multifaceted
nature
pyrolysis,
operating
across
diverse
temporal
spatial
scales,
kinetics-based
CFD–DEM
method
is
employed
to
predict
yields.
Results
showed
that
elevated
content
amplifies
particle
adhesiveness,
necessitating
augmented
velocities
effective
separation,
thereby
influencing
efficiency
separation
process.
While
carbon
hydrogen
contents
exhibit
relative
stability
blower
frequencies,
oxygen
undergoes
noticeable
changes.
For
example,
were
measured
as
29.2
38.6
wt%
in
light
fraction
30
%
sample
at
frequencies
10
20
Hz,
respectively.
An
intriguing
finding
emerges
from
simulation,
indicating
lower
frequency
moderately
enhances
bio-oil
yield
significantly
improves
its
quality,
particularly
terms
water
instance,
was
about
1.5
heavy
fractions,
respectively
under
15
Hz
frequency.
In
summary,
detailed
understanding
strategic
manipulation
critical
material
attributes
through
efficient
fractionation
techniques
are
imperative
advancing
fast
sustainable
avenue
renewable
energy
chemical
production.
