Modular burner and furnace comprising this burner

Abstract

This burner comprises a porous support (6) and a combustion tube (2) along which the porous support (6) is mounted, the combustion tube (2) having one or more openings to let a fuel through to the porous support (6), characterized in that the combustion tube (2) is formed of a plurality of tubular modules (20) that are connected together and in that the burner (1) further comprises at least one distribution tube extending inside the combustion tube (2) to distribute the fuel in a predetermined manner in the combustion tube.

Description

[0001] The present invention relates to a burner and an oven comprising this burner.

[0002] Burners are combustion devices designed to produce heat by burning a mixture of fuel (classically a gas) and an oxidizer (usually air).

[0003] There are different types of burners, such as atmospheric burners, forced-air burners, or premix burners.

[0004] Premix burners are burners where air is mixed with gas in a premix chamber, with or without the aid of a fan, before being distributed onto the surface of a porous support where the flame develops.

[0005] It is known to produce this porous support by an assembly of metallic fibers. The fibers are classically made of a fire-resistant alloy, for example Fecralloy®, configured to resist corrosion at temperatures above 1000°C.

[0006] These metallic fibers can be woven to create a flexible textile capable of producing a wide variety of shapes. The metallic textile is traditionally mounted on a steel casing containing distribution plates designed to ensure even combustion.

[0007] Porous support burners offer numerous advantages over other burners, such as homogeneous combustion with a wide modulation range. These burners allow for heat transfer either by radiation (infrared) or convection (blue flame), as well as an easy transition between these two modes of heat transfer. Furthermore, porous support burners offer high thermal efficiency with low emission levels (CO, NOx), low pressure drop, low thermal inertia, safety against flashback, and resistance to mechanical and thermal shock.

[0008] It is thus known to use porous support burners in various fields such as drying or surface treatment of paints or coatings, heat treatment of technical textiles, or even for cooking food such as biscuits, pancakes, breads, brioches, etc., in agri-food ovens.

[0009] Generally, porous support burners can extend to a length of approximately 2 to 3 meters. However, in the case of food processing ovens, where the burners are positioned perpendicular to a conveyor belt carrying the food to be cooked, the width of this conveyor belt can exceed 4 to 8 meters. Therefore, there is a need for large burners.

[0010] One drawback of large burners is their deformation due to expansion. This deformation generates a pronounced bow, also known as the banana effect, which can affect the evenness of cooking and the lifespan of the burner (tearing of the metal fabric).

[0011] Another disadvantage of large burners is their size and weight. This increases transport costs and can complicate their installation inside baking ovens.

[0012] Another drawback is the edge effect occurring at the sides of the oven. The same amount of energy must be supplied across the entire width of the conveyor belt to ensure even cooking. Since the heat is lower at the sides of the oven due to energy absorption by its lateral walls, a large burner is needed to compensate for these edge effects.

[0013] US 4 543 940 relates to a burner according to the preamble of claim 1. CN 204 213 927 U relates to a modularized flame treatment burner system device. WO 2008 / 003869 relates to a tunnel oven, particularly for biscuit manufacturing.

[0014] Therefore, the present invention aims to overcome all or part of these disadvantages by proposing a burner allowing a reduction in deflection, a reduction in size to reduce transport costs and facilitate assembly, and a homogeneous heat transfer over its entire length.

[0015] To this end, the present invention relates to a burner as defined by claim 1 and comprising a porous support and a combustion tube along which the porous support is mounted, the combustion tube having one or more openings to allow fuel to pass to the porous support, characterized in that the combustion tube is formed of a plurality of tubular modules assembled together and in that the burner further comprises at least one distribution tube extending inside the combustion tube to distribute the fuel in a predetermined manner in the combustion tube.

[0016] Thus, the burner according to the invention, through its combustion tube formed by an assembly of modular sections, allows for a large burner while limiting deflection and reducing size and transport costs. The distribution tube ensures homogeneous fuel distribution within the combustion tube.

[0017] The opening(s) of the combustion tube are slots orthogonal to a longitudinal axis of the burner.

[0018] This allows fuel to pass more easily to the porous support.

[0019] Advantageously, the burner has a feed module comprising sparking means and one or more sparking orifices arranged under the sparking means and configured to allow more fuel to pass through than a section of the same length of the combustion tube.

[0020] This allows an excess of fuel to be sent to the sparking means in order to facilitate sparking.

[0021] According to one embodiment, in which the burner includes fastening means configured to securely fix adjacent tubular modules.

[0022] According to one embodiment, the fastening means include fastening flanges bearing against each other.

[0023] This flange-to-flange contact between the support and the surface ensures an effective seal between two modules. It also helps to reduce deflection.

[0024] According to one embodiment, the fixing flanges support said at least one distribution tube inside the combustion tube.

[0025] According to one embodiment, the fastening means include calibrated leakage means allowing fuel to pass into the porous support at the junction of adjacent tubular modules.

[0026] This ensures flame continuity at the junction of two modules. These calibrated leakage means can be formed by a notched portion of the mounting flanges.

[0027] This feature creates a pressure drop aimed at better distributing the fuel within the combustion tube.

[0028] According to the invention, the burner comprises several distribution tubes, including a primary distribution tube intended to distribute the fuel into a first combustion zone formed by one or more tubular modules of the combustion tube, and at least one secondary distribution tube configured to distribute the fuel in a predetermined manner into a combustion zone downstream of the first combustion zone and formed by one or more other tubular modules of the combustion tube.

[0029] This allows for the independent management of multiple combustion zones.

[0030] Advantageously, said at least one secondary distribution tube includes a blind portion extending at least through said first combustion zone.

[0031] According to the invention, both the primary distribution tube and said at least one secondary distribution tube have a perforated part having an upstream portion having a perforation area larger than a downstream portion.

[0032] This feature ensures flame continuity. It prevents a dark area from appearing at the beginning of the perforated section due to the fuel's propagation speed.

[0033] A larger perforation area on an upstream portion compared to a downstream portion of the perforated section of the distribution tube means that the total perforated surface area is greater than that of a downstream portion of the same length. Therefore, more fuel escapes through this upstream portion than through a downstream portion of the same length.

[0034] Note that upstream and downstream are defined here in relation to the overall direction of fuel flow inside the burner.

[0035] According to one embodiment, the primary distribution tube and said at least one secondary distribution tube have a perforated part comprising distribution orifices arranged opposite the porous support.

[0036] This feature allows for better fuel distribution. The fuel flow is not obstructed by the presence of the other distribution tube(s).

[0037] According to one embodiment, the primary distribution tube and said at least one secondary distribution tube have a terminal portion comprising an axial plug and a radial outlet opening.

[0038] This slows down the arrival of fuel at the end of the combustion tube zone and creates a pressure drop aimed at better distributing the fuel within the combustion tube.

[0039] Advantageously, the radial outlet is arranged opposite the porous support.

[0040] According to one embodiment, the terminal portion is arranged at a distance from a downstream end of the corresponding combustion zone, preferably at an upstream end of the last of the tubular modules forming said corresponding combustion zone.

[0041] This feature allows for a homogeneous distribution of fuel in the corresponding area of ​​the combustion tube, avoiding an excess of fuel in the last tubular module of this area.

[0042] Advantageously, the perforated portion of each distribution tube extends along only a part of the corresponding zone of the combustion tube. In particular, each zone of the combustion tube is formed of several consecutive tubular modules, and the terminal portion extends into the last tubular module of the corresponding zone, near the upstream end of that tubular module, the terminal portion being preferably closer to the upstream end than to the downstream end of the last tubular module of the corresponding zone.

[0043] According to one embodiment, the burner includes adjustment means configured to independently regulate the fuel flow entering each distribution tube.

[0044] According to another aspect, the invention also relates to an oven comprising a burner having the aforementioned characteristics.

[0045] Other features and advantages of the present invention will become clear from the following detailed description of an embodiment, given by way of non-limiting example, with reference to the accompanying drawings in which: [ Fig. 1 ] is a perspective view of a burner according to an explanatory embodiment, but not according to the invention, [ Fig. 2 ] is a top view of a portion of the combustion tube of a burner according to an explanatory embodiment, but not according to the invention, [ Fig. 3 ] is a perspective view of a tubular module of the combustion tube of a burner according to an explanatory embodiment, but not according to the invention, [ Fig. 4 ] is a perspective view of a junction between two consecutive tubular modules of a burner according to an explanatory embodiment, but not according to the invention, [ Fig. 5 ] is a cross-sectional view of a burner according to an explanatory embodiment, but not according to the invention, at the junction between two consecutive tubular modules of this burner, [ Fig. 6 ] is a cross-sectional view along a longitudinal median axis of the tubular module of the figure 3 , [ Fig. 7 ] is an exploded perspective view of a burner according to an explanatory embodiment, but not according to the invention, showing a burner power supply module, [ Fig. 8 ] is a perspective view of a burner power supply module according to an explanatory embodiment, but not according to the invention, [ Fig. 9 ] is a top view of a portion of a burner power supply module according to an embodiment of the invention, [ Fig. 10 ] is a perspective view of a burner according to an embodiment of the invention, [ Fig. 11 ] is a perspective and transparent view of a first combustion zone of the burner of the figure 10 , [ Fig. 12 ] is an exploded perspective and transparent view of a second combustion zone of the burner of the figure 10 , [ Fig. 13 ] is an exploded perspective and transparent view of a third combustion zone of the burner of the figure 10 , [ Fig. 14 ] is a top view of an upstream portion of the perforated part of a burner distribution tube according to an embodiment of the invention, [ Fig. 15 ] is a top view of a portion of the perforated part of a burner distribution tube according to an embodiment of the invention, downstream of the portion of the figure 14 , [ Fig. 16 ] is a perspective and transparent view of the last module of the first combustion zone of the burner of the figure 10 , [ Fig. 17 ] is a perspective and transparent view of the last module of the first combustion zone of the burner of the figure 10 , [ Fig. 18 ] is a perspective and transparent view of a burner power supply module according to an embodiment of the invention.

[0046] There figure 1 The illustration shows a burner 1 according to an explanatory embodiment, but not according to the invention. The burner 1 is intended to equip an oven, in particular a food processing oven. The burner 1 extends longitudinally along an axis A, preferably over a length of at least 4 m, and which may be, for example, between 4 and 8 meters. The burner 1 is therefore a large burner.

[0047] The burner 1 comprises a combustion tube 2 formed of several tubular modules 20, a distribution tube 4 arranged inside the combustion tube 2, and a porous support 6 supported by the combustion tube 2 and on the surface of which a premix of air and gas is intended to burn. The burner 1 is advantageously a premixed surface combustion burner.

[0048] The porous support 6 is a fuel-permeable support, for example, a premix of gas and air. The porous support 6 advantageously comprises metallic fibers, which can be woven so that the porous support 6 forms a flexible metallic fabric. These metallic fibers are made of a fire-resistant alloy, configured to resist corrosion at temperatures exceeding 1000°C, such as Fecralloy®.

[0049] The porous support 6 selectively allows the use of either radiative (infrared) or convective (blue flame) heat transfer, and offers an easy transition between these two modes. Radiative (infrared) heat transfer refers to a heat transfer with a power density on the order of 100 to 500 kW·m⁻². Convective (blue flame) heat transfer refers to a heat transfer with a power density on the order of 500 to 10,000 kW·m⁻².

[0050] The combustion tube 2 extends longitudinally along axis A and supports the porous support 6. The porous support 6 can be attached to the combustion tube 2 by spot welding (fusion of the fabric forming the porous support 6 with the combustion tube 2). The porous support 6 therefore also extends longitudinally along axis A, specifically along the entire length of the combustion tube 2.

[0051] The combustion tube 2 is hollow and advantageously cylindrical. The combustion tube 2 has an upstream end, connected and sealed by a feed module 8, and a downstream end, connected and sealed by a closure module 10.

[0052] The combustion tube 2 is perforated. As shown on the figure 2 The combustion tube 2 has, along its lateral wall, a plurality of combustion openings 22, which pass through and are arranged beneath the porous support 6 to allow fuel to flow from the inside of the combustion tube 2 to the porous support 6 where combustion takes place. These openings 22 can be arranged longitudinally at regular intervals from each other. They have the form of slots orthogonal to the longitudinal axis A. For example, they are aligned along the axis A, as illustrated in the figure 2 .

[0053] The combustion tube 2 comprises a plurality of tubular modules 20 aligned and connected end-to-end to form the combustion tube 2. Each tubular module 20 thus constitutes a section of the combustion tube. As can be seen in the figure 3 Each tubular module 20 supports a portion of the porous support 6. Furthermore, each tubular module 20 includes through-holes, such as those illustrated in the figure 2 allowing the fuel to pass from the inside of the tubular module 20 to the porous support 6.

[0054] The 20 tubular modules are advantageously similar. In particular, they can be of equal length. Following the example of the figure 1 The combustion tube 2 comprises eight tubular modules 20. It could comprise fewer or more. Thus, according to the example of the figure 10 , which will be described in more detail below, the combustion tube 2 comprises for example nine tubular modules 20.

[0055] The 20 tubular modules are joined end to end to form the combustion tube. For this purpose, as can be seen on the figure 3 The burner 1 includes fastening means for rigidly and securely fixing the adjacent tubular modules 20. These fastening means include, in particular, fixing flanges 24, intended to be pressed together in pairs, these flanges 24 being able to be held tightly against each other by screw-nut type clamping means.

[0056] The fixing flanges 24 can be arranged at the ends of the tubular modules 20. Thus, each tubular module 20 comprises a first fixing flange 24 at an upstream end 20a of the tubular module 20, and a second fixing flange 24 at a downstream end. The first fixing flange 24 of a tubular module 20 is intended to be fixed to the second fixing flange 24 of a preceding tubular module 20.

[0057] The flanges 24, possibly plate-shaped, have a flange projecting radially from the side wall of the tubular modules 20 and thus from the combustion tube. The flanges 24 are, for example, orthogonal to the longitudinal axis A. The mounting flanges 24 have an advantageously flat mounting face 240, designed to receive the mounting face of another mounting flange 24.

[0058] Preferably, the mounting flanges 24 do not extend all the way around the combustion tube. They may, in fact, have a primary notch 242 allowing the passage of the porous support 6 at the junction of two adjacent tubular modules 20. As illustrated in the figure 4 (where the porous support 6 is not shown), the mounting flanges 24 may include one or more secondary notches 244 at the bottom of the primary notch 242, to allow gas to escape towards the porous support 6 at the junction of the tubular modules 20. This or these secondary notches 244 form calibrated leakage means, between the tubular module 20 and the porous support 6 on the one hand, and between two adjacent tubular modules 20 on the other. The calibrated leakage means are located below the porous support 6, to ensure flame continuity at the junction of two tubular modules 20.

[0059] Advantageously, the flanges 24 for fixing do not only extend outside the combustion tube 2, forming a collar, but also inside the combustion tube 2, forming a partition wall 246 preventing the passage of fuel located in the combustion tube 2 from one tubular module 20 to the other (except via calibrated leakage means), as illustrated in the figure 3 This partitioning allows for a more homogeneous distribution of the fuel along the burner 1. The partition wall 246 extends in an annular manner around the distribution tube(s) 4 responsible for distributing the fuel into the tubular modules 20.

[0060] The mounting flanges 24 may have one or more axial through openings 248 allowing the passage of a distribution tube 4. Each through opening 248 preferably has a shape complementary to that of the distribution tube 4 it receives. The through opening(s) 248 extend through the partition wall 246 to allow the distribution tube(s) to pass through the junction of two adjacent tubular modules 20. Following the example of the figure 3 The fixing flanges 24 comprise a single, central, through opening 248, allowing passage of the single distribution tube 4. According to the embodiment of the invention of figures 10 à 18 , the fixing flanges 24 include one, two or three through openings 248 each allowing the passage of a separate distribution tube 4.

[0061] The mounting flanges 24 thus seal the ends of the tubular modules 20, except to create the calibrated leak or to allow the passage of the distribution tubes 4 from one module 20 to the other. The mounting flanges 24 also support the distribution tubes 4 that extend inside the combustion tube 2. These distribution tubes 4 rest on the inner edge defining the corresponding through opening 248.

[0062] The distribution tubes 4 are intended to distribute the fuel in a predetermined manner within the combustion tube 2. Each distribution tube 4 extends inside the combustion tube, along the longitudinal axis A, and includes (see for example the figure 18 ) an inlet port 40 allowing the fuel to enter. This inlet port 40 can extend inside a feed module 8 of the burner 1.

[0063] Unlike the combustion tube 2, the distribution tubes 4 are advantageously not modularly designed and can extend in a single piece from their upstream end, where the inlet port is located, to their downstream end. The distribution tubes 4 have a smaller diameter than the combustion tube 2 to allow fuel to flow around the distribution tubes 4, i.e., within the combustion tube 2, once the fuel has left the distribution tube 4.

[0064] As described previously, each distribution tube 4 can be supported and held in place inside the combustion tube 2 by means of the fixing flanges 24.

[0065] Each distribution tube 4 includes a perforated portion 42, comprising one or more distribution orifices 420 (see figures 14, 15 ) through a side wall of the distribution tube 4, to allow the passage of fuel from the inside of the distribution tube 4 into the combustion tube 2. The distribution orifices 420 may be in the form of slots, advantageously orthogonal to the longitudinal axis A of the burner 1. They may be arranged in a staggered pattern.

[0066] With reference to the figure 6 The burner 1 comprises, not according to the invention, a single distribution tube 4 and therefore a single combustion zone. This single distribution tube 4, more precisely its perforated portion 42, extends through all the tubular modules 20 of the combustion tube 2 in order to distribute the fuel into each of these tubular modules 20, along the entire length of the burner 1. As can be seen in the figure 6 In this case, the distribution orifices 420 are preferably arranged diametrically opposite the porous support 6 in order to distribute the mixture homogeneously within the combustion tube. Furthermore, these distribution orifices 420 can be distributed at regular intervals along axis A, and for example, aligned.

[0067] With reference to the figure 10 , and to figures 11 à 18 The burner 1 according to the invention comprises several distribution tubes 4 for creating several combustion zones A, B, C that can be controlled independently of each other. Each distribution tube 4 is intended to distribute fuel into a predetermined combustion zone of the combustion tube 2.

[0068] In particular, these distribution tubes 4 include a primary distribution tube 4 which is intended to distribute the fuel in the combustion zone A furthest upstream of the combustion tube 2, and one or more (two depending on the example of the figures 10 à 13 ) 4 secondary distribution tubes intended to distribute fuel to combustion zones B, C located downstream.

[0069] For example, as illustrated on the figures 10 à 13 The combustion tube 2 comprises three combustion zones A, B, C, and consequently three distribution tubes 4 to distribute the fuel to each of the three combustion zones A, B, C. It should be noted here that each combustion zone can be formed by the same number of tubular modules 20, for example three (the combustion tube 2 here comprising nine tubular modules 20). figure 11 shows the first combustion zone, the figure 12 the second combustion zone, the figure 13 the final combustion zone.

[0070] The primary and secondary distribution tubes 4 all include a perforated portion 42 having distribution orifices 420 intended to allow the passage of fuel from the interior of the distribution tube 4, primary or secondary, to the corresponding area of ​​the combustion tube 2. These distribution orifices 420 are preferably arranged opposite the porous support 6. The perforated portion 42 extends preferably from the first to the penultimate of the tubular modules 20 forming the combustion area concerned.

[0071] With reference to figures 14 et 15 It should be noted that the perforated portion 42 has an upstream section 42a which, for the same segment length, has a larger perforation area than a downstream section 42b. In particular, the upstream section 42a has more distribution orifices 420 than a segment of the same length of the downstream section 42b and / or distribution orifices 420 distributed over a wider angle than for the downstream section 42b. Preferably, the distribution orifices 420 of the upstream section 42a are arranged all around, i.e., at 360°, around the axis A. The downstream section 42b has distribution orifices 420 distributed over an angular range, for example, between 100° and 140°, preferably between 110° and 130°, for example 119°, around the axis A.

[0072] With reference to figures 16 et 17 The perforated portion 42 of the primary and secondary distribution tubes 4 advantageously comprises a terminal portion 44 which is axially closed by a deflector plug 440, allowing the fuel to slow down at the end of the combustion zone, as illustrated in the figure 17 Furthermore, as can be seen on the figure 16 The terminal section 44 includes a radial outlet 442 for releasing the remaining fuel inside the last tubular module 20 of the corresponding combustion zone. Unlike the distribution orifices 420 of the perforated section 42, this radial outlet 442 is advantageously arranged diametrically opposite the porous support 6.

[0073] It should be noted that the terminal portion 44 extends into the last of the tubular modules 20 forming the combustion zone served by the corresponding distribution tube 4. Preferably, this terminal portion 44 is located at the upstream end 20a of this tubular module 20, or at least at a distance from the downstream end 20b, advantageously closer to the upstream end 20a than to the downstream end 20b. The terminal portion 44 extends over a significantly shorter length than the perforated portion 42. For example, the length of the distribution tube 4 in the last tubular module 20 of the combustion zone served is less than one-fifth, preferably less than one-tenth, of the length of this tubular module 20.

[0074] The secondary distribution tubes 4 further include a blind portion 46 which is located upstream of their perforated portion 42. This blind portion 46, in the form of a tube without perforations on its lateral wall, is intended to extend through the combustion zone(s) located upstream of that served by the perforated portion 42 of the same distribution tube 4.

[0075] With reference to the figure 11 The first combustion zone A is formed by the first three tubular modules 20.1, 20.2, 20.3 of the combustion tube 2, and the primary distribution tube 4A extends through these first three tubular modules 20.1, 20.2, 20.3. In particular, the perforated part 42 of the primary combustion tube 2 extends through the first and second tubular modules 20.1, 20.2. At the beginning of the combustion zone A, i.e. at the upstream end of the first tubular module 20.1, the perforated part 42 has an upstream portion 42a having a larger perforation area than a downstream portion, for example at 360°. In the remainder of the first tubular module 20.1, as well as in the second tubular module 20.2, the perforated section 42 has perforations arranged opposite the porous support 6, with a perforation area smaller than the upstream portion 42a, for example at 119°. Finally, in the third and last tubular module 20.forming this first combustion zone A, the primary distribution tube 4 includes a terminal part 44 having the deflector plug 440 and a radial outlet opening 442. This terminal part 44 extends near the upstream end 20a of the last of the tubular modules 20.3 forming the first combustion zone A, over about one tenth of the length of this last tubular module 20.3.

[0076] With reference to the figure 12 The second combustion zone B is formed by the next three tubular modules 20.4, 20.5, 20.6 (fourth, fifth, and sixth modules) of the combustion tube. The secondary distribution tube 4, which supplies the third combustion zone C, has its blind section 46 extending through modules 20.4, 20.5, and 20.6, so that it does not distribute fuel into this second combustion zone B. The perforated section 42 of the secondary distribution tube 4 supplying the second combustion zone B extends through the fourth and fifth tubular modules 20.4 and 20.5. At the beginning of the second combustion zone B, i.e., at the upstream end of the fourth tubular module 20.4, the perforated section 42 has an upstream portion 42a with a larger perforation area, for example, 360°, than the downstream portion 42b. In the remainder of the fourth tubular module 20.4, as well as in the fifth tubular module 20.5, the perforated portion 42 has distribution orifices 420 arranged opposite the porous support 6, with a perforation area smaller than the upstream portion 42a, for example at 119°. Finally, in the sixth and last tubular module 20.6 forming this second combustion zone B, the secondary distribution tube 4 serving this second combustion zone B includes a terminal portion 44 having a deflector plug 440 and a radial outlet opening 442. This terminal portion 44 extends near the upstream end of the last of the tubular modules 20.6, over approximately one-tenth of the length of this last tubular module 20.6.

[0077] With reference to the figure 13 The third combustion zone C is formed by the next three tubular modules 20.7, 20.8, 20.9 (seventh, eighth, and ninth modules) of the combustion tube. The perforated portion 42 of the secondary distribution tube 4 serving this third combustion zone C extends through the seventh and eighth tubular modules 20.7, 20.8. At the beginning of the third combustion zone C, i.e., at the upstream end of the seventh tubular module 20.7, the perforated portion 42 has an upstream portion 42a with a larger perforation area, for example, 360°, than a downstream portion 42b. In the remainder of the seventh tubular module 20.7, as well as in the eighth tubular module 20.8, the perforated portion 42 has distribution orifices 420 arranged opposite the porous support 6, with a perforation area smaller than the upstream portion 42a, for example at 119°. Finally, in the ninth and last tubular module 20.forming this third combustion zone C, the distribution tube 4 includes a terminal part 44 having a deflector plug 440 and a radial outlet opening 442. This terminal part 44 extends near the upstream end of the last of the tubular modules 20.9, over about one tenth of the length of this last tubular module 20.9.

[0078] As previously stated, the burner 1 includes a feed module 8 connected upstream of the combustion tube 2 to supply each distribution tube 4 with fuel. The feed module 8, as well as the closure module 10 if present, can be connected to the first, and respectively the last, of the tubular modules 20 forming the combustion tube 2 by means of the previously described fastening means, such as the fastening flanges 24. The feed module 8 enables the supply of fuel to the distribution tube(s) 4.

[0079] The burner 1 advantageously includes means for regulating the fuel flow rate entering each distribution tube 4. Having several distribution tubes 4, the regulating means allow the fuel flow rate for each distribution tube 4 to be adjusted independently of each other. As illustrated in the figure 18 The adjustment means may include, for each distribution tube 4, an adjustment screw 80.

[0080] With reference to figures 8 And 9 The power supply module 8 includes sparking means, such as electrodes 82 visible on the figure 8enabling combustion, and a terminal portion connected to the first tubular module 20, this terminal portion 84 comprising one or more sparking orifices 840 passing through a side wall of the feed module 8 below the sparking means to allow fuel to pass to the sparking means. The porous support 6 extends between the sparking means and the sparking orifice(s) 840. For a given section length, the perforation area of ​​this terminal portion 84 is advantageously larger than that of the combustion tube 2 downstream. The sparking orifices 840 may be in the form of slots, advantageously orthogonal to the longitudinal axis A of the burner 1. These sparking orifices may be arranged in a staggered pattern.

[0081] The invention also relates to an oven comprising a burner 1 as previously described. In particular, this oven can be a food-grade oven intended for baking foods such as biscuits, pancakes, bread, brioches, etc.

[0082] Of course, the invention is by no means limited to the embodiment described above, this embodiment having been given only as an example. Modifications are possible, particularly with regard to the construction of the various devices, without departing from the scope of protection of the invention.

Claims

1. A burner (1) comprising a porous support (6) and a combustion tube (2) along which the porous support (6) is mounted, the combustion tube (2) having one or several openings for allowing a fuel to pass towards the porous support (6), wherein the combustion tube (2) is formed of a plurality of tubular modules (20) assembled to each other, and wherein the burner (1) further comprises at least one distribution tube (4) extending inside the combustion tube (2) to distribute the fuel in a predetermined manner within the combustion tube, the burner (1) comprising several distribution tubes (4), including a primary distribution tube (4) intended to distribute the fuel in a first combustion area formed by one or several tubular modules (20) of the combustion tube, and at least one secondary distribution tube (4) configured to distribute the fuel in a predetermined manner in a downstream combustion area relative to the first combustion area and formed by one or several other tubular modules (20) of the combustion tube, the burner being characterized in that the opening(s) (22) of the combustion tube (2) are slots orthogonal to a longitudinal axis (A) of the burner (1), and in that both the primary distribution tube (4) and said at least one secondary distribution tube (4) have an openwork part (42) having an upstream portion (42a) with a greater perforation area than a downstream portion (42b) of the same length as the upstream portion (42a), the total perforated surface area of the upstream portion (42a) being greater than that of the downstream portion (42b).

2. The burner (1) according to claim 1, wherein the burner (1) comprises fastening means configured to sealingly fasten adjacent tubular modules (20).

3. The burner (1) according to the preceding claim, wherein the fastening means comprise fastening flanges (24) bearing against each other.

4. The burner (1) according to the preceding claim, wherein the fastening flanges (24) support said at least one distribution tube (4) inside the combustion tube.

5. The burner (1) according to any of claims 2 to 4, wherein the fastening means comprise calibrated leakage means allowing fuel to pass towards the porous support (6) at the junction of the adjacent tubular modules (20).

6. The burner (1) according to any of claims 1 to 5, wherein the primary distribution tube (4) and said at least one secondary distribution tube (4) have the openwork part (42) comprising distribution orifices (420) arranged facing the porous support (6).

7. The burner (1) according to any of claims 1 to 6, wherein the primary distribution tube (4) and said at least one secondary distribution tube (4) have a terminal portion comprising an axial plug (440) and a radial outlet opening (442).

8. The burner (1) according to the preceding claim, wherein the terminal portion is arranged at a distance from a downstream end of the corresponding combustion area, preferably at an upstream end of the last of the tubular modules (20) forming said corresponding combustion area.

9. The burner (1) according to any of claims 1 to 8, wherein the burner (1) comprises adjustment means configured to independently adjust the fuel flow rate entering each distribution tube (4).

10. A furnace comprising a burner (1) according to any of the preceding claims.

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