Energies,
Journal Year:
2024,
Volume and Issue:
17(19), P. 4959 - 4959
Published: Oct. 3, 2024
To
improve
energy
savings
and
emission
reduction
in
industrial
heating
furnaces,
this
study
investigated
the
impact
of
various
molar
fractions
hydrogen
on
natural
gas
combustion
compared
results
Non-Premixed
Combustion
Model
with
Eddy
Dissipation
Model.
Initially,
an
furnace
was
experimentally,
these
were
used
as
boundary
conditions
for
CFD
simulations.
The
diffusion
flame
characteristics
simulated
using
both
non-premixed
model
indicated
that
provided
simulations
more
consistent
experimental
data,
within
acceptable
error
margins,
thus
validating
accuracy
numerical
Additionally,
to
analyze
doping
performance
heater,
four
mixtures
varying
contents
(15%
H2,
30%
45%
60%
H2)
studied
while
maintaining
constant
fuel
inlet
temperature
flow
rate.
demonstrate
accurately
simulates
complex
flue
chemical
reactions
during
combustion.
Moreover,
hydrogen-doped
significantly
reduces
CO
CO2
emissions
pure
Specifically,
at
content,
levels
decrease
by
70%
37.5%,
respectively,
NO
increase
proportionally;
concentration
chamber
rises
155%.
Applied Thermal Engineering,
Journal Year:
2024,
Volume and Issue:
256, P. 124127 - 124127
Published: Aug. 6, 2024
A
Micro-Thermal
Photovoltaic
(MTPV)
system
with
a
Tesla-shaped
micro
combustor
is
proposed
and
studied
to
enhance
thermal
performance,
electrical
power
output,
energy
efficiency,
acoustic
performance.
The
present
study
focuses
on
three
key
parameters:
(1)
inlet
velocity,
(2)
equivalence
ratio,
(3)
combustion
channel
dimensions.
We
introduce
novel
method
analyze
the
performance
of
MTPV
by
integrating
combustion,
heat
transfer,
space
radiation
diffusion,
photovoltaic
effect
numerically.
Additionally,
prevent
blow-off
in
combustor,
we
incorporate
Tesla
valve-shaped
design.
reverse
direct
flow
configuration
shown
lead
better
efficiency
compared
forward
configuration.
Furthermore,
optimal
output
are
achieved
under
stoichiometric
conditions.
Under
6
m/s,
an
inner
diameter
(D8)
2
mm
reaches
8.36
%,
surpassing
that
D8
8
2.36
%.
This
highlights
positive
impact
increasing
varying
both
efficiency.
transmission
loss
initially
experiences
increase
followed
subsequent
decrease
flow.
In
contrast,
flow,
higher
44.68
dB
18.85
specifically
at
20
Hz
4500
Hz.
Consequently,
notably
superior
particularly
high
frequencies
low
frequencies.
Blending
co-combustion
fuel
is
an
effective
strategy
for
improving
the
low
combustion
performance
of
ammonia
(NH3),
enabling
its
use
as
a
power
fuel.
In
this
study,
impact
and
underlying
reasons
types
blending
ratios
low-carbon
alkanes
(methane
ethane,
C1/C2)
on
NH3
were
elucidated
at
level
chemical
reaction
mechanisms
efficacy
reactive
radicals,
through
experimental
numerical
simulation
approaches.
Using
dimethyl
ether
reference
to
estimate
energy
efficiency
supply.
The
research
indicates
that
C1/C2
can
improve
emission
levels
NH3.
enhancement
effect
more
pronounced
with
C2,
particularly
when
ratio
less
than
or
equal
0.5.
disparity
in
effects
stems
from
different
chain
dehydrogenation
reactions
number
C-H
bonds.
CH3
radicals
generated
initial
C1
bind
H,
hindering
subsequent
reactions.
inert
C2
appear
later,
occurring
H
structure
four.
However,
adverse.
leads
increase
peak
concentration
NO,
but
oxidation
produces
NH
NH2,
reducing
most
fuel-NO.
This
reduction
not
significant
thermal-NO.
addition
increases
intensity
N→NO
reaction,
thereby
increasing
proportion
thermal-NO
difficult
consume.
Physics of Fluids,
Journal Year:
2024,
Volume and Issue:
36(12)
Published: Dec. 1, 2024
As
one
of
the
most
promising
zero-carbon
fuels,
ammonia
has
attracted
widespread
attention.
However,
combustion
faces
problems
such
as
high
nitrogen
oxide
emissions.
This
work
aims
to
investigate
characteristics
fuel
gas
mixture
60%
NH3
and
40%
CH4
by
volume,
under
five
different
equivalence
ratios,
i.e.,
0.7,
0.85,
1.0,
1.15,
1.3,
respectively.
Both
large
eddy
simulation
(LES)
experimental
test
are
conducted.
The
results
reveal
that
flame
temperature
nitric
(NO)
emissions
exhibit
an
initial
increase,
followed
a
decrease
with
rising
ratios.
Notably,
highest
is
observed
at
ϕ
=
while
peak
NO
emission
found
0.85.
ratio
changes,
variation
turbulent
flow
fields
mass
recirculation
rates
not
significant.
On
contrary,
OH
radicals
distinct
shifts
in
relation
ratio.
predicted
LES
agree
well
results.
A
chemical
reaction
network
(CRN)
analysis
also
conducted,
which
effectively
predicts
trends
clarifies
generation
pathways
key
mechanisms.
CRN
highlights
variations
sensitivities
crucial
constituents,
NH3,
OH,
NO,
