Note: Descriptions are shown in the official language in which they were submitted.
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HIGH INTENSITY GAS FIRED INFRARED EMITTER
Cross-Reference to Related Applications
[0001] This
application claims the benefit of U.S. Provisional Patent Application Serial
No. 62/306,214, filed on March 10, 2016 and entitled "High Intensity Gas Fired
Infrared
Emitter", the entire disclosure of which is incorporated herein by reference.
Field of the Invention
[0002] The present
disclosure is directed generally to high intensity gas-fired infrared
emitters, and more specifically, to high intensity gas-fired infrared emitters
including a flame
arrestor and a cellular combustion member to provide improved conversion
efficiency.
Bac keround
[0003] Gas-fired
radiant emitters are used, for example, for drying coating, controlling
moisture profiles, processing industrial building equipment, curing, and other
applications
that require a large amount of heat to be transferred to a load in a very
short amount of time.
Typically, many emitters are positioned side-by-side to extend across an
industrial automated
machine or production line.
[0004]
Unfortunately, a lot of time is required to maintain a large number of
emitters
positioned side-by-side. Moreover, conventional gas-fired radiant emitters
produce carbon
monoxide (CO) emissions at 100 ppm and nitrogen oxide (N0x) emissions at 30
ppm, both
referenced to 3% 02 in dry flue products, which are undesirable. It is
advantageous to
improve the overall conversion efficiency of gas-fired radiant emitters.
Summary of the Invention
[0005] The present
disclosure is directed generally to high intensity gas-fired infrared
emitters including a flame arrestor and a cellular combustion member to
provide improved
conversion efficiency. The disclosed embodiments provide advantages over
conventional
emitters by making the device less prone to instances of backfire during
operation.
Additionally, the disclosed embodiments minimize energy loss through
components of the
emitter near the external surface which transfers heat. The combination of a
flame arrestor
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and cellular surface panel allows for a high surface area with minimal losses,
resulting in
improved conversion efficiency.
[0006] Generally, in
one aspect, a high intensity gas-fired infrared emitter is provided.
The high intensity gas-fired infrared emitter includes (i) a frame having a
plurality of side
walls, an open bottom, and an open top; (ii) a flame arrestor mounted inside
the frame and
including a bottom, a top surface having a recess, and a plurality of
apertures extending from
the bottom to the recessed top surface; and (iii) a cellular surface panel
formed of a plurality
of cells and mounted inside the recess of the flame arrestor such that the
plurality of
apertures of the flame arrestor form pathways which extend into the cellular
surface panel.
100071 According to
an embodiment, each of the plurality of cells of the cellular surface
panel comprises a geometry to form a restricted path for products of
combustion.
[0008] According to
an embodiment, the cellular surface panel comprises at least two
consecutively connected solid porous bodies.
[0009] According to
an embodiment, at least two consecutively connected solid porous
bodies have different sizes.
100101 According to
an embodiment, the emitter further includes a body mounted
within the frame and a resilient element configured to retain the flame
arrestor, the cellular
surface panel and the body within the frame.
[0011] According to
an embodiment, the body supports a deflector plate positioned
dimensionally offset relative to the body.
[0012] According to
an embodiment, an offset is arranged between the flame arrestor
and the body mounted within the frame to increase a volume of a chamber formed
therein.
[0013] According to
an embodiment, the flame arrestor is made of a lightweight
ceramic fiber material composed principally of aluminum oxide and silicon
dioxide.
[0014] According to
an embodiment, the emitter further includes a fire check assembly
coupled to the body to stop gas flow to the cellular surface panel in a
failure event.
[0015] Generally, in
another aspect, a high intensity gas-fired infrared emitter is
provided. The high intensity gas-fired infrared emitter includes (i) a frame
having at least
one side wall, an open bottom, and an open top; (ii) a flame arrestor mounted
inside the
frame and including a bottom, a top surface having a recess, and a plurality
of apertures
extending from the bottom to the recessed top surface; (iii) a cellular
surface panel mounted
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inside the recess of the flame arrestor such that the plurality of apertures
of the flame
arrestor form pathways which extend into the cellular surface panel; and (iv)
a fire check
assembly coupled with the emitter. The assembly includes a solder joint
positioned
proximate a gas outlet, and a plunger rod fixed to the solder joint and in a
compressed state
via a resilient member. The solder joint is configured to break when exposed
to a flame
causing the plunger rod to be displaced to close a gas inlet.
[0016] According to
an embodiment, the resilient member is a spring urging the plunger
rod towards the gas inlet.
[0017] According to
an embodiment, the cellular surface panel comprises at least two
consecutively connected solid porous bodies.
[0018] According to
an embodiment, the flame arrestor is made of a lightweight
ceramic fiber material composed principally of aluminum oxide and silicon
dioxide.
[0019] According to
an embodiment, the cellular surface panel is formed from silicon
carbide (Si-SiC).
[0020] Generally, in
a further aspect, a method of operating a high intensity gas-fired
infrared emitter is provided. The emitter includes a frame, a flame arrestor
mounted inside
the frame, and a cellular surface panel mounted inside the flame arrestor. The
method of
operating includes the steps of (i) introducing a combustible mixture into the
high intensity
gas-fired infrared emitter through an inlet manifold; (ii) dispersing the
combustible mixture
into a cavity; (iii) forcing, by a deflector plate, the combustible mixture to
fill a chamber,
(iv) forming a pressure tight seal within the chamber; (v) passing the
combustible mixture
through apertures within the flame arrestor to maintain a low air-gas
temperature prior to
combustion; and (vi) igniting the mixture to heat cells of the cellular
surface panel.
100211 According to
an embodiment, the chamber is formed by at least one gasket, the
flame arrestor, a cast iron body, the frame, and at least one resilient
member.
[0022] It should be
appreciated that all combinations of the foregoing concepts and
additional concepts discussed in greater detail below (provided such concepts
are not
mutually inconsistent) are contemplated as being part of the inventive subject
matter
disclosed herein. In particular, all combinations of claimed subject matter
appearing at the
end of this disclosure are contemplated as being part of the inventive subject
matter disclosed
herein. It should also be appreciated that terminology explicitly employed
herein that also
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may appear in any disclosure incorporated by reference should be accorded a
meaning most
consistent with the particular concepts disclosed herein.
Brief Description of the Drawings
[0023] The
foregoing will be apparent from the following more particular description
of example embodiments of the present disclosure, as illustrated in the
accompanying
drawings in which like reference characters refer to the same parts throughout
the different
views. The drawings are not necessarily to scale, emphasis instead being
placed upon
illustrating embodiments of the present disclosure.
[0024] FIG. 1 is a
schematic cross-sectional view of a high intensity gas-fired infrared
emitter assembly, according to an embodiment of the present disclosure.
[0025] FIG. 2 is a
schematic perspective view of a flame arrestor, according to an
embodiment of the present disclosure.
[0026] FIG. 3 is a
schematic view of a cellular surface panel, according to an
embodiment of the present disclosure.
[0027] FIG. 4 is a
schematic top view of a cast iron body, according to an
embodiment of the present disclosure.
[0028] FIG. 5 is a
schematic cross-sectional view of a fire check assembly, according
to an embodiment of the present disclosure.
Detailed Description of Embodiments
[0029] A
description of example embodiments of the invention follows. Although the
gas-fired infrared emitter assembly shown in the figures is shown in an upward
orientation,
the gas-fired infrared emitter is typically operated in the downward
orientation. Thus, the
description of the assembly shown in the figures is not intended to be limited
to a particular
orientation. The terms "top" and "bottom" as used herein describe elements of
the assembly
based on the upward orientation of the assembly shown in the figures. In other
words, for
example, the "open bottom side 4A" also represents "an open top side" when the
assembly is
rotated 180 degrees in use.
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[0030] Referring to
FIG. 1, a high intensity gas-fired infrared emitter assembly is
shown schematically in a cross-sectional view according to an example
embodiment of the
present disclosure. A metallic housing is formed from a high temperature
metal, such as,
stainless steel. The high intensity gas-fired infrared emitter broadly
includes a frame 1, a
flame arrestor 9, and a cellular surface panel 10. In the embodiment shown in
FIG. 1, the
frame 1 comprises four vertical side walls 2, four horizontal edges 3 formed
as a 90-degree
continuation of each of the side walls 2, an open bottom side 4A, a
substantially open top side
4B defined by the horizontal edges 3 and extensions 7, and four tabs 2A (two
on each of the
side walls 2) that contain slots 5. The flame arrestor 9 is mounted inside the
frame 1 and
includes a bottom, a top surface having a recess, and apertures 44 extending
from the bottom
to the recessed top surface. Cellular surface panel 10 is formed from silicon
carbide (Si-
SiC) and located within the confines of the flame arrestor 9.
[0031] To retain the
cellular surface panel in place within the flame arrestor 9,
extensions 7 are included either integrally or otherwise within frame 1.
Extensions 7 extend
from horizontal edges 3 in a direction away from side walls 2. Extensions 7
can be made of
any suitable metal, for example, stainless steel. In an example embodiment,
two extensions 7
are arranged on each of the longer sides of a rectangular frame 1. Additional
or fewer
extensions are contemplated. Any suitable sizes and shapes of extensions are
contemplated.
In an example embodiment, the horizontal edges 3 include indentations such
that the non-
indented portions retain the cellular surface panel in place within the flame
arrestor 9. The
slots 5 within the frame 1 are arranged to receive resilient elements 6 on
each side of the
emitter. Resilient elements 6 can be springs or any suitable alternative.
[0032] In an example
embodiment, metallic components are formed inside each of the
four comers of the frame 1. Such metallic components can be formed from a high
temperature metal, such as, stainless steel, or any suitable alternative. The
metallic corner
components can be sized such that at least 0.5 inches of metallic material,
for example,
extends in length and width directions, normal to the open horizontal face 4B.
The corner
components can be fixed into position mechanically via a weld or any suitable
alternative
along with additional compression force produced by resilient elements 6.
[0033] A rectangular
gasket 8 is arranged inside the outer edge of frame 1 and within
the boundary of the horizontal edges 3. The rectangular gasket 8 can be made
from high
temperature ceramic paper or any suitable alternative. Coincident to the
bottom side of paper
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gasket 8 is a flame arrestor 9, formed of high temperature ceramic fiber
insulation or any
suitable alternative.
[0034] Referring to
FIG. 2, a perspective schematic view of the flame arrestor 9 is
shown according to an example embodiment of the present disclosure. The flame
arrestor 9
includes four side walls 40 that fit dimensionally inside metallic frame 1.
The side walls 40
can be integral or separately formed. In an example embodiment, each of the
four side walls
40 is defined by a wall thickness 41 of approximately 0.33 inches. Wall
thickness 41 may
define the shape of recess 42. Recess 42 extends vertically downward to a
point
approximately forty percent of the total height of side walls 40 of the flame
arrestor 9.
Apertures 44 are formed from the bottom 43 through the top plane of recess 42
within the
remaining sixty percent of the total height of side walls 40. In an example
embodiment,
apertures 44 are approximately 0.04-0.06 inches in diameter and formed by
drilling.
However, any suitable method of forming apertures 44 is contemplated. In an
example
embodiment, the apertures are arranged in a regular pattern. In an example
embodiment, the
apertures are arranged in an irregular pattern. The center-to-center distance
between
apertures 44 may be in the range of 0.15-0.3 inches, for example, and the
density of the
apertures 44 may be spread evenly across the plane of recess 42 to provide a
total number of
apertures in the range of 600-800. However, additional or fewer apertures are
contemplated
and the apertures need not be spread evenly across the plane of recess 42. The
apertures 44
are arranged such that the apertures communicate with (i.e., form pathways
which extend
into) the cellular geometry of cellular surface panel 10 (shown in FIG. 1).
[0035] The flame
arrestor 9 may be formed of a lightweight ceramic fiber material
suitable for 3000 F and composed principally of aluminum oxide (A1203) and
silicon dioxide
(SiO2). In an example embodiment, the suitable material is composed of
approximately 78
percent aluminum oxide (A1203) and/or 22 percent silicon dioxide (SiO2) and/or
a density of
25 lb/ft3. The flame arrestor 9 also may exhibit continuous use up to 2950
degrees Fahrenheit
(or 3000 degrees Fahrenheit), thermal conductivity of 1.25 Btu/(hr)(ft2)(
F/in), and 2.3
percent shrinkage at 2500 degrees Fahrenheit. The high temperature range, high
compressive
strength, and minimal shrinkage allow the material to be processed with 400-
800 holes, for
example, without any surface cracking ensuring long emitter life. The
insulation properties
of the flame arrestor 9 effectively hold an air/gas mixture temperature on the
bottom side of
the flame arrestor 9 (where an air/gas mixture enters the emitter)
approximately 2300 degrees
Fahrenheit lower than a main combustion zone on the opposite side. The flame
arrestor 9
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effectively insulates the frame 1 from the cellular surface panel 10, thus
minimizing losses
and increasing conversion efficiency of the emitter.
[0036] The cellular
surface panel 10 may have a profile that substantially corresponds
in shape and size to the flame arrestor recess 42 and to the top opening 4B of
the frame 1.
FIG. 3 shows a schematic view of the cellular surface panel 10 including an
inner surface 45,
side walls 46, and an external surface 47, opposite the inner surface 45. The
cellular surface
panel 10 may be made of Si-SiC, which provides a high thermal conductivity,
emissivity,
shock resistance, and lower coefficient of thermal expansion required to
retain overall life of
the emitter as it is subjected to extremely high thermomechanical loading. Any
suitable
alternative or combination of alternatives which provide(s) substantially
similar
characteristics is contemplated. Viewing the cellular surface panel in detail,
cell 48 can be
embodied as a truncated cube or truncated hexahedron having about fourteen
regular faces,
thirty-six edges, and twenty-four vertices. Cell 48, and all consecutively
connected cells,
may have diameters of differing sizes ranging from 0.05-0.15 inches, for
example, extruded
through each of the faces, increasing viewpoint surface area exposure through
the external
surface 47. The increased surface area created by the consecutively connected
and layered
cells (truncated cubes) provides over five times the amount of surface area
than the surface
area of the external surface 47.
[0037] Referring
back to FIG. 1, a ceramic paper gasket 8A that is of similar shape
and size of the ceramic paper gasket 8 is arranged coincident to the underside
of the flame
arrestor 9. On the bottom side of the ceramic paper gasket 8A may be
rectangular gasket 11
of graphite composition, sized to correspond with the ceramic paper gasket 8A.
A cast iron
body 12 may be positioned to rest against the graphite gasket 11 inside the
confines of the
frame 1. The general convex envelope of the cast iron body 12 and the offset
distance
created by the ceramic paper gaskets 8A and 11 forms chamber 13 between cast
iron body 12
and the flame arrestor 9.
[0038] Referring to
FIG. 4, a schematic top view of a cast iron body 12 is shown
including pegs 49 positioned within the cast iron body 12. Pegs 49 extend
vertically to
support the deflector plate 15 (shown in FIG. 1). The pegs 49 may be
positioned such that
the total amount on each side of axis 50 is equal. However, the number of pegs
shown in
FIG. 4 is only illustrative and additional or fewer pegs are contemplated. The
deflector plate
15 may be formed from alloy or mild steel and can include four side walls that
are offset
dimensionally relative to the inside of the inner side walls 52 of the cast
iron body 12.
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Dimensional offset 16 (shown in FIG. 1) between the deflector plate 15 and the
inner side
walls 52 (shown in FIG. 4) of the cast iron body 12 may be equal around all
four sides. Two
pegs 51 can be arranged on each side of axis 50 and can include female threads
that
communicate with openings in the deflector plate 15. Screws can be included to
retain the
deflector plate 15 in place within the cast iron body 12. Vertical support
pegs 49 and a
casting inlet manifold 17 (shown in FIG. 1) form a cavity 19 underneath the
deflector plate
15, which communicates with the chamber 13 through the offset gap 16 around
all sides of
the casting body 12. Cast iron body 12 may include female threads at an inlet
manifold 17 to
accept a fire check assembly 18 in an example embodiment.
[0039] FIG. 5
illustrates a schematic cross-sectional view of a fire check assembly 18.
The fire check assembly can include a short pipe nipple 53, a union 54, a pipe
nipple 55, an
insert 56, a frame 61, a plunger 62, and a resilient element 67. The resilient
element 67 can
be a spring or any suitable alternative. The short iron pipe nipple 53
communicates with the
union 54, and the iron pipe nipple 55 maintains a threaded connection
relationship with the
union 54. The insert 56 may have an outer diameter that allows it to be press
fitted into
position inside the iron pipe nipple 55, flush with a bottom face 57. The
insert 56 may
include a bore 58, a counter-bore 59, and two slots 60 to accept both sides
61A of the frame
61. The counter-bore 59 may be dimensioned such that it accepts plunger 62 if
the two
surfaces have a coincident relationship. Frame 61 may be formed of mild steel
strip of
approximately 1/8 inches thickness and 0.2 inches width, for example. Two 90-
degree
bends form sides 61A, which correspond to the inner diameter/length of the
pipe run,
which includes the short nipple 53, union 54, and pipe nipple 55. Cross
members 64 and
66 may be positioned to support sides 61A, which may be fixed in position by
mechanical
weld or any suitable alternative. Each frame cross member includes a hole
drilled
concentric to bore 58 to communicate/guide plunger rod 65. Plunger rod 65 is
fixed in place
at solder joint 63. Resilient element 67 is compressed against cross member
66. Resilient
element 67 may be dimensioned such that its inner diameter corresponds with
the outer
diameter of plunger rod 65 (allowing ease of movement), and has a length such
that sufficient
compression force remains present with plunger 62 in a coincident position
with counter-bore
59. The fire check assembly 18 may be dimensioned such that the top of the
frame 61 may
be inserted inside the inlet casting manifold 17 of the emitter with, for
example,
approximately 1/3 inches clearance to the bottom side of the deflector plate
15.
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[0040] With
reference to FIGS. 1-5, operation of the high intensity gas-fired infrared
emitter is explained as follows. A pre-mixed air/gas (e.g., natural gas or
propane) mixture
can be introduced into fire check assembly 18 in an air-to-gas ratio of, for
example,
approximately 10:1 for natural gas (25:1 for propane) sufficient to, when
ignited, produce
flames and products of combustion. The flame arrestor 9 allows for a reduced
amount of
excess air compared to prior technologies as excess air is not required for
cooling of the
emitter. A reduction in flow path area is encountered by the air-gas mixture
upon entering
assembly 18, caused by insert 56 as well as frame 61 and plunger 62. The
reduction in flow
path area may be sufficient to limit the overall energy input to the emitter
(based on its
maximum operating conditions), while at the same time providing enough back
pressure to
allow any premix manifold to distribute the proper mixture equally to
pluralities of emitters
when positioned side-by-side to extend cross directionally.
[0041] Once the air-
gas mixture exits the fire check assembly 18, the air-gas mixture is
introduced into the infrared emitter through the casting inlet manifold 17
where it expands
into the annular casting manifold before dispersing into the cavity 19, formed
from the
general convex envelope of the cast iron body 12. Once the air/gas mixture
reaches the
cavity 19, it encounters the deflector plate 15, which forces the air-gas
mixture to fill the
chamber 13 through the offset gap 16 (around all sides of the casting body
12), ensuring
equal distribution and uniform emitter surface temperature profile.
[0042] The ceramic
paper gasket 8A, graphite gasket 11, flame arrestor 9, casting
body 12, frame 1, and resilient elements 6 not only allow the formation of
chamber 13, but
can also create a pressure tight seal. The gasket combination 8A and 11 can
create an
increased offset between the flame arrestor 9 and the casting body 12,
increasing the volume
of chamber 13 and dwell time of the air/gas mixture, further improving
distribution
effectiveness. The casting body 12, frame 1, and resilient elements 6 may be
configured such
that when in the assembled position, resilient elements 6 exert a homogeneous
compressive
force on the casting body 12, which compresses gaskets 8A and 11 and the flame
arrestor 9
against the horizontal edges 3 of the frame 1. The composition of gasket 11 is
such that the
gasket spreads when compressed to fill any small voids that may be present
between the
casting body 12, frame 1, and flame arrestor 9. Additional sealing
characteristics are
achieved as the temperature of the graphite gasket 11 is increased beyond room
temperature.
[0043] Once the
reactants have reached the chamber 13, the mixture is forced to pass
through apertures 44 in the flame arrestor 9. In an example embodiment,
apertures 44 are
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annular nozzles. The flow path travel distance through each aperture in the
flame arrestor 9
is such that there is enough material to insulate the air-gas mixture in the
chamber 13 from
the combustion zone temperatures on the recess 42, maintaining a low air-gas
premix
temperature inside of the emitter (prior to combustion), which is vital in
reducing the
occurrence of backfire during normal operation of the emitter. The flame
arrestor 9 also
insulates the metallic vertical side walls 2 of the frame 1 from the cellular
surface panel 10.
This effect minimizes energy loss through parts of the emitter near the
external surface 4B
(the surface of the emitter that is meant to transfer heat). The material
composition of the
flame arrestor 9 can both ensure proper function through the insulation of the
chamber 13 and
minimize losses through the frame 1.
[0044] As the gas
mixture enters the inlet of each aperture 44, the fluid velocity
increases, creating well defined fluid streams that extend into the
interconnected truncated
cubes of the cellular surface panel 10. An external ignition source may ignite
the mixture and
each of the apertures 44 can form very well defined flames that reach the top
of the surface
47 of the cellular surface panel (shown in FIG. 3). As the individual flames
heat the portion
of the cells into which they extend, the reaction also releases products of
combustion that
circulate within the cellular structure prior to reaching the external surface
47. The complex
geometry of the cellular surface panel 10 forms a restricted path for the
products of
combustion, which, through transmission, transfer heat to the steady stream of
reactants that
continue to flow through the emitter body. The combustion methodology forces
all flames to
dissipate, moving the combustion zone into the lower half of the cellular
surface panel 10,
concurrently. The stabilization of combustion within the bottom half of the
cellular surface
panel permits an ongoing internal recuperation of heat and forms a homogeneous
temperature
field across the surface of the infrared emitter, referred to herein as
"cellular combustion."
Cellular combustion generates a very large temperature difference in the
products of
combustion when measured at the initial point of generation and at the point
of exiting the
external surface 47, increasing overall emitter conversion efficiency and
creating a peak
energy wavelength that extends well into the short wavelength spectrum. The
peak energy
wavelength ranges between 780 nm to 1 mm. The combination of the disclosed
flame
arrestor and cellular surface panel provides a high surface area with minimal
losses, resulting
in a very high conversion efficiency. Further, nitrogen oxide (N0x) emissions
are less than
15 ppm at ten percent excess air at nominal firing rates and carbon monoxide
(CO) emissions
are typically at less than 100 ppm at ten percent excess air at nominal firing
rates. Moreover,
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in installations using multiple emitters, significantly fewer emitters are
required due to the
emitters' efficiency, thus decreasing the time required for routine
maintenance.
[0045] In an event
that the emitter is operated outside the specified operating range
and/or in an event or string of events that leads to failure (e.g., backfire
into the chamber
13), solder joint 63 of the frame 61 and the plunger rod 65 are positioned to
cause quick
failure of the joint 63. Failure of the joint 63 releases the compression
force caused by
resilient element 67 resting in a compressed position against cross member 66.
Movement
of resilient element 67 from a compressed state to an uncompressed state
releases the
compression force, moving plunger 62 into a coincident position with counter-
bore 59. The
length of resilient element 67 is such that the opposite side of resilient
element 67 remains in
contact with cross member 66 causing enough of a compression force on plunger
62 to shut
off the air/gas flow into the emitter.
[0046] While this
invention has been particularly shown and described with
references to example embodiments thereof, it will be understood by those
skilled in the art
that various changes in form and details may be made therein without departing
from the
scope of the invention encompassed by the appended claims. For example, the
cells 48 of the
cellular surface panel 10 can be formed of any particular solid porous body
geometry. The
cellular surface panel 10 can be formed of any number of consecutively
connected solid
porous body geometries, can have any number of layers, and can be held in
place using
additional structural support extending from horizontal edges 3 of the frame
1. The flame
arrestor 9 can have a recess 42 of any depth and wall thickness to accommodate
the
dimensional boundaries that define the cellular surface panel 10, can have any
number of
apertures, not necessarily round, in any pattern, and the apertures may
contain larger recessed
holes for increased retention aperture surface area.
[0047] While several
inventive embodiments have been described and illustrated
herein, those of ordinary skill in the art will readily envision a variety of
other means and/or
structures for performing the function and/or obtaining the results and/or one
or more of the
advantages described herein, and each of such variations and/or modifications
is deemed to
be within the scope of the inventive embodiments described herein. More
generally, those
skilled in the art will readily appreciate that all parameters, dimensions,
materials, and
configurations described herein are meant to be exemplary and that the actual
parameters,
dimensions, materials, and/or configurations will depend upon the specific
application or
applications for which the inventive teachings is/are used. Those skilled in
the art will
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recognize, or be able to ascertain using no more than routine experimentation,
many
equivalents to the specific inventive embodiments described herein. It is,
therefore, to be
understood that the foregoing embodiments are presented by way of example only
and that,
within the scope of the appended claims and equivalents thereto, inventive
embodiments may
be practiced otherwise than as specifically described and claimed. Inventive
embodiments of
the present disclosure are directed to each individual feature, system,
article, material, and/or
method described herein. In addition, any combination of two or more such
features, systems,
articles, materials, and/or methods, if such features, systems, articles,
materials, and/or
methods are not mutually inconsistent, is included within the inventive scope
of the present
disclosure.
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