EP3426980A1

EP3426980A1 - High intensity gas fired infrared emitter

Info

Publication number: EP3426980A1
Application number: EP17764215.4A
Authority: EP
Inventors: Chris E. VANDEGRIFT; Mitchell D. CORNELIUS; Jens-Uwe Meyer; Timothy M. O'NEAL
Original assignee: Selas Heat Technology Company LLC
Current assignee: Solaronics SAS
Priority date: 2016-03-10
Filing date: 2017-03-10
Publication date: 2019-01-16
Anticipated expiration: 2037-03-10
Also published as: EP3426980A4; US20170261204A1; WO2017156440A8; MX2018010935A; CA3017360A1; JP2019507861A; EP3426980B1; KR20180121600A; CN117927947A; WO2017156440A1; CN109328283A

Abstract

A high intensity gas-fired infrared emitter including a frame having a plurality of side walls, an open bottom, and an open top, 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 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.

Description

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.

Background

[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 (NO_x) emissions at 30 ppm, both referenced to 3% O2 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 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.

[0007] 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.

[0010] 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 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.

[0021] 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 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. [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 corners 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 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 (AI₂O₃) and silicon dioxide (S1O₂). In an example embodiment, the suitable material is composed of approximately 78 percent aluminum oxide (A1₂0₃) and/or 22 percent silicon dioxide (S1O₂) 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 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 8 A 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. 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 61 A, 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 61 A, 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. [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 8 A, 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 1 1 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 8 A and 1 1 and the flame arrestor 9 against the horizontal edges 3 of the frame 1. The composition of gasket 1 1 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 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 intemal 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 (NOx) 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, 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 j oint 63 of the frame 61 and the plunger rod 65 are positioned to cause quick failure of the j oint 63. Failure of the j oint 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 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.

Claims

Claims What is claimed is:

1. A high intensity gas-fired infrared emitter, comprising:

a frame having a plurality of side walls, an open bottom, and an open top;

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

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.

2. The high intensity gas-fired infrared emitter of claim 1 , wherein each of the plurality of cells of the cellular surface panel comprises a geometry to form a restricted path for products of combustion.

3. The high intensity gas-fired infrared emitter of claim 1 , wherein the cellular surface panel comprises at least two consecutively connected solid porous bodies.

4. The high intensity gas-fired infrared emitter of claim 3, wherein the at least two consecutively connected solid porous bodies have different sizes.

5. The high intensity gas-fired infrared emitter of claim 1, further comprising 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.

6. The high intensity gas-fired infrared emitter of claim 5, wherein the body supports a deflector plate positioned dimensionally offset relative to the body.

7. The high intensity gas-fired infrared emitter of claim 5, wherein an offset is arranged between the flame arrestor and the body mounted within the frame to increase a volume of a chamber formed therein.

8. The high intensity gas-fired infrared emitter of claim 1, wherein the flame arrestor is made of a lightweight ceramic fiber material composed principally of aluminum oxide and silicon dioxide.

9. The high intensity gas-fired infrared emitter of claim 1 , further comprising a fire check assembly coupled to the body to stop gas flow to the cellular surface panel in a failure event.

10. A high intensity gas-fired infrared emitter, comprising:

a frame having at least one side wall, an open bottom, and an open top;

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;

a cellular surface panel 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; and

a fire check assembly coupled with the emitter, the assembly further comprising: a solder j oint positioned proximate a gas outlet; and

a plunger rod fixed to the solder j oint and in a compressed state via a resilient member;

wherein the solder j oint is configured to break when exposed to a flame causing the plunger rod to be displaced to close a gas inlet.

1 1. The high intensity gas-fired infrared emitter of claim 10, wherein the resilient member is a spring urging the plunger rod towards the gas inlet.

12. The high intensity gas-fired infrared emitter of claim 10, wherein the cellular surface panel comprises at least two consecutively connected solid porous bodies.

13. The high intensity gas-fired infrared emitter of claim 10, wherein the flame arrestor is made of a lightweight ceramic fiber material composed principally of aluminum oxide and silicon dioxide.

14. The high intensity gas-fired infrared emitter of claim 10, wherein the cellular surface panel is formed from silicon carbide (Si-SiC).

15. A method of operating a high intensity gas-fired infrared emitter, the emitter comprising a frame, a flame arrestor mounted inside the frame, and a cellular surface panel mounted inside the flame arrestor, the method comprising the steps of:

introducing a combustible mixture into the high intensity gas-fired infrared emitter through an inlet manifold;

dispersing the combustible mixture into a cavity;

forcing, by a deflector plate, the combustible mixture to fill a chamber;

forming a pressure tight seal within the chamber;

passing the combustible mixture through apertures within the flame arrestor to maintain a low air-gas temperature prior to combustion; and

igniting the mixture to heat cells of the cellular surface panel.

16. The method of claim 15, wherein the chamber is formed by at least one gasket, the flame arrestor, a cast iron body, the frame, and at least one resilient member.