JP5909900B2 - Combustion heater and combustion heating system - Google Patents

Description

  The present invention relates to a combustion heater that burns fuel and heats an object to be heated, and a combustion heating system that connects a plurality of combustion heaters.

  2. Description of the Related Art Conventionally, a combustion heater that heats a radiator with combustion heat obtained by burning fuel gas and heats industrial materials, foods, and the like with radiation heat from a radiation surface of the radiator has been widely used. For such a combustion heater, for example, a technique of applying a material and shape having a high emissivity to the radiation surface in order to improve the radiation intensity has been proposed (for example, Patent Document 1).

  In the conventional combustion heater described above, the fuel gas is burned at the flame opening provided on the surface of the radiation surface, and the exhaust gas is exhausted to the surrounding environment without being recovered. Therefore, the exhaust heat cannot be recovered, the thermal efficiency is lowered, and the area of the radiation surface is reduced by the area of the flame opening, so that the radiation intensity cannot be increased. Furthermore, the environmental temperature around the device rises due to the heat of the exhaust gas, or the exhaust gas is full, and the working environment may not be improved.

  Therefore, a combustion heater with improved thermal efficiency has been proposed. This combustion heater has a sealed structure from the fuel gas introduction path to the combustion chamber and the exhaust gas outlet path after combustion, the introduction path and the outlet path are adjacent to each other, and the fuel gas before combustion is heated by the heat of the exhaust gas. Is preheated to increase thermal efficiency (for example, Patent Document 2).

JP 2004-324925 A JP 2007-212082 A

  The combustion heater as in Patent Document 2 described above is composed of a heating plate having a radiation surface, an arrangement plate arranged to face the heating plate, a partition plate arranged between the heating plate and the arrangement plate, and the like. A space sandwiched between the partition plates serves as a fuel gas introduction path. This arrangement plate is required to have high surface accuracy and high-temperature oxidation resistance for forming a fuel gas introduction path, and also requires rigidity to form a part of the casing. Since the combustion heater uses a member that satisfies such a plurality of requirements as the arrangement plate, the manufacturing cost has been increased.

  In view of such a problem, the present invention provides a combustion heater capable of ensuring sufficient rigidity of a casing while forming an introduction path for introducing fuel gas into a combustion chamber with high accuracy with an inexpensive configuration. And to provide a combustion heating system.

In order to solve the above problems, a combustion heater of the present invention is arranged along the outer periphery of a heating plate, an arrangement plate disposed opposite to the heating plate, the heating plate and the arrangement plate, the heating plate and the arrangement plate, In the space surrounded by the outer peripheral wall surrounding the space, the partition plate arranged between the heating plate and the arrangement plate, the heating plate, the arrangement plate, and the outer peripheral wall, arranged along the outer peripheral wall inside the outer peripheral wall The combustion chamber, the first heat insulating portion arranged continuously on the outer peripheral wall side surface and the arrangement plate side surface of the combustion chamber, and the arrangement plate and the partition plate are used as side walls to continuously guide the fuel gas to the combustion chamber. An introduction path, a heating plate and a partition plate as side walls, and a lead-out path that leads exhaust gas from the combustion chamber to the outside of the combustion heater continuously to the combustion chamber and preheats the fuel gas with the heat of the exhaust gas through the partition plate; A support plate for supporting the placement plate from the opposite side with respect to the introduction path of the placement plate, and an outer peripheral wall Between, and a space extending in the direction of introduction of the fuel gas to the combustion chamber is formed.

The arrangement plate may be provided with a notch that fits the first heat insulating portion and forms a gap between the arrangement plate and the first heat insulating portion.
The 1st heat insulation part may be formed with the material which is excellent in high temperature oxidation resistance rather than a support plate.
The arrangement plate may be made of a material that has better high-temperature oxidation resistance than the support plate.

  You may further provide the 2nd heat insulation part which is pinched between the arrangement | positioning board and the support plate, and has heat insulation.

In order to solve the above problems, a combustion heating system of the present invention includes a heating plate, a placement plate disposed opposite to the heating plate, and arranged along the outer periphery of the heating plate and the placement plate. In the space surrounded by the outer peripheral wall surrounding the space, the partition plate arranged between the heating plate and the arrangement plate, the heating plate, the arrangement plate, and the outer peripheral wall, arranged along the outer peripheral wall inside the outer peripheral wall The combustion chamber, the first heat insulating portion arranged continuously on the outer peripheral wall side surface and the arrangement plate side surface of the combustion chamber, and the arrangement plate and the partition plate are used as side walls to continuously guide the fuel gas to the combustion chamber. An introduction path, a heating plate and a partition plate as side walls, and a lead-out path that leads exhaust gas from the combustion chamber to the outside of the combustion heater continuously to the combustion chamber and preheats the fuel gas with the heat of the exhaust gas through the partition plate; A combustion heating system in which a plurality of combustion heaters are connected to the introduction path of the arrangement plate And a support plate which is a series of plate members for supporting a plurality of arrangement plates in the plurality of combustion heaters connected from the opposite side, and a fuel gas to the combustion chamber is provided between the outer peripheral wall and the arrangement plates. A space extending in the introduction direction is formed.

  According to the present invention, it is possible to ensure sufficient rigidity of the casing while forming an introduction path for introducing the fuel gas into the combustion chamber with high accuracy with an inexpensive configuration.

It is the external appearance perspective view which showed the external appearance example of the combustion heating system. It is the perspective view which showed the AA cross section of FIG. It is the perspective view which showed the inner side of the combustion heating system. It is BB sectional drawing of FIG. It is BB sectional drawing of FIG. 1 in a modification. It is an assembly drawing for demonstrating the structure of a combustion heater. It is explanatory drawing for demonstrating a some projection part.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  The combustion heater has a combustion chamber, a fuel gas (unburned gas: gas before combustion) introduction path, and an exhaust gas (combustion gas: gas after combustion) outlet path sealed in a main body container. Excess enthalpy combustion is realized in the combustion chamber by preheating the fuel gas that is formed in the state and that flows through the inlet passage with the heat of the exhaust gas that flows through the outlet passage. Since such a combustion heater recovers the heat of the exhaust gas, the heat efficiency is high and the exhaust gas itself is also recovered, so that the working environment is not impaired. Further, since no flame opening is required, there is an advantage that the radiation area is not reduced and the radiation intensity is high.

  Among such combustion heaters, in particular, in the disk-type combustion heater, the partition plate responsible for heat transfer is a thin plate smaller than a pair of thin plates (heating plate, arrangement plate), and between the pair of thin plates. Heat is exchanged between the introduction path and the lead-out path with a simple configuration in which a gap is provided in the arrangement. Furthermore, since the disk-type combustion heater has a high degree of freedom in the shape of a thin plate having a radiation surface and a high degree of freedom in the arrangement of the combustion chamber, the combustion load factor (unit volume in the combustion chamber can be increased by taking a larger combustion chamber. Heat generation) and local deterioration and damage can be avoided.

  Due to the ease of use that achieves both high thermal efficiency and exhaust gas recovery function, the conventional combustion heater that exhausts the exhaust gas after combustion to the surrounding environment as it is will be used in the disc-type combustion of this embodiment. Opportunities to replace with heaters are expected to increase. However, many of the current disk-type combustion heaters are relatively small, and due to size restrictions, conventional large-sized combustion heaters cannot be immediately replaced with disk-type combustion heaters.

  Here, if an attempt is made to increase the amount of heat and the heating area of the disk-type combustion heater and the combustion heater is simply increased in a two-dimensional direction, the manufacturing cost increases in order to stably maintain the sealing property. , The thermal deformation of the partition plate separating the introduction path and the outlet path in the combustion heater is increased, the temperature distribution is biased, and the CO emission concentration due to incomplete combustion is increased. There is a risk that the performance cannot be fully exhibited. Therefore, the inventor of the present application paid attention to a combustion heating system in which a plurality of combustion heaters are connected in series. Here, the continuous arrangement means that the combustion heaters are provided in a continuous state, and includes that a plurality of combustion heaters are integrally formed.

  In the combustion heater constituting such a combustion heating system, a space sandwiched between the arrangement plate and the partition plate is a fuel gas introduction path. Therefore, the arrangement plate is required to have high surface accuracy and high-temperature oxidation resistance for forming a fuel gas introduction path, and further, when it forms a part of the housing, rigidity is also required. When such a highly functional material is used, the manufacturing cost of the combustion heater has been increased.

  The combustion heating system in which a plurality of combustion heaters in the present embodiment are connected in series has an inexpensive configuration and ensures sufficient rigidity of the casing while forming an introduction path for introducing fuel gas into the combustion chamber with high accuracy. Is possible.

(Combustion heating system 100)
1 is an external perspective view showing an external appearance example of the combustion heating system 100, FIG. 2 is a perspective view showing an AA cross section of FIG. 1, and FIG. 3 shows an internal state of the combustion heating system 100. FIG. In FIG. 3, in order to demonstrate the inner side of the combustion heating system 100, the state which removed the heating plate is shown.

  As shown in FIGS. 1 to 3, the combustion heating system 100 includes a plurality of (in this case, two) combustion heaters 110 connected in series. Heat and collect the exhaust gas.

  Further, as shown in FIGS. 2 and 3, a fire transfer portion 102 that communicates with the sealed space in the combustion heater 110 provided continuously is formed at a connection portion between the combustion heaters 110. However, even if it is a sealed space, it is not always necessary to completely seal it when used in a gas. In the combustion heating system 100 of the present embodiment, for example, a single flame is ignited by an ignition device such as an igniter (not shown), and the flame spreads and is ignited in all the combustion heaters 110 connected through the fire transfer section 102. The

  Here, in order to realize a large amount of heat and a heating area, a plurality of combustion heaters 110 having a relatively small amount of heat and a heating area are combined. In this way, individual thermal deformation can be suppressed as compared with the case where the combustion heater 110 alone is designed to be large. In addition, even if the combustion heater 110 is further connected in accordance with the demand for an increase in the amount of heat and the heating area, the individual combustion capacity is not affected by the increase in the combustion heater 110. Can be maintained. Here, for convenience of explanation, the case where only two combustion heaters 110 are connected is described, but the combustion heater 110 is arbitrarily connected in the longitudinal direction and the short direction of the combustion heater 110. The combustion heating system 100 with various aspect ratios can be formed.

(Combustion heater 110)
4 is a cross-sectional view taken along the line BB in FIG. As shown in FIG. 4A, the combustion heater 110 includes a heating plate 118, an arrangement plate 120, an outer peripheral wall 122, a partition plate 124, a combustion chamber 126, an introduction path 128, and a lead-out path 130. The support plate 132, the first heat insulating part 134, the second heat insulating part 136, the third heat insulating part 138, the first pipe part 140, and the second pipe part 142 are configured. In the present embodiment, the combustion heater 110 will be described as an example having an outer shape of about 220 mm × 140 mm (440 mm × 140 mm when two are provided in the longitudinal direction). However, the external shape of the combustion heater 110 is not limited to this size, and can be set to an arbitrary size.

  The combustion heater 110 in the present embodiment is a premixed type in which a fuel gas (premixed gas) in which a city gas or the like and air as a combustion oxidant gas are mixed in advance is supplied to the main body container. It is not limited to such a case, but may be a diffusion type in which both are mixed to perform diffusion combustion in the combustion chamber 126 or the introduction path 128 immediately before the combustion chamber 126.

  The heating plate 118 and the arrangement plate 120 are arranged to face each other and are made of a material having high heat resistance and high temperature oxidation resistance, for example, stainless steel (SUS: Stainless Used Steel), or a material having high heat conductivity, for example, brass ( Brass) or the like, and arranged substantially parallel to each other (substantially parallel for causing excess enthalpy combustion in the present embodiment). The heating plate 118 also functions as a radiator that is heated by the combustion heat generated in the combustion chamber 126.

  Further, the heating plate 118 is provided with a concavo-convex portion 118a in which concavo-convex portions are formed. With this configuration, the unevenness 118a absorbs the difference in thermal expansion due to the temperature difference between the heating plate 118 and the arrangement plate 120 and the difference between the materials of the heating plate 118 and the arrangement plate 120, and the coupling portion with the outer peripheral wall 122, etc. Therefore, thermal fatigue and high temperature creep due to repeated heating and cooling can be suppressed. Moreover, since the area of the radiation surface of the heating plate 118 is increased, the radiation intensity can be increased.

  The outer peripheral wall 122 has an inner periphery formed into a track shape (a shape composed of two substantially parallel line segments and two arcs (semicircles) connecting the two line segments) and a rectangular outer periphery when viewed from above. (See FIG. 3), arranged along the outer periphery of the heating plate 118 and the arrangement plate 120, and the heating plate 122 and the arrangement plate 120 surround the space. Moreover, the outer peripheral surface of the outer peripheral wall 122 can also be used as a radiation surface. In this embodiment, the outer peripheral wall 122 is formed integrally with a support plate 132 described later, but may be formed separately.

  In the combustion heater 110, the area of the heating plate 118 is larger than the area of the outer surface of the outer peripheral wall 122. When the heating plate 118 becomes a radiation surface and the fuel gas burns in the combustion chamber 126, heat is transmitted from the radiation surface by radiation or air convection to heat the object to be heated. Further, when a plurality of combustion heaters 110 are connected in series as in the combustion heating system 100, substantially the same radiant heat can be obtained on the radiation surfaces of the plurality of combustion heaters 110. In the present embodiment, the upper surface (the upper surface of the heating plate 118) of the upper and lower wall surfaces of the combustion heater 110 is a radiation surface. However, the present invention is not limited to this case, and the lower surface (the support plate 132 described later). The lower surface may be a radiating surface, or both the upper and lower wall surfaces may be radiating surfaces.

  The partition plate 124 has a smaller outer shape than the heating plate 118 and is formed in a shape along the inner peripheral surface of the outer peripheral wall 122 (see FIG. 3), and the heating plate 118 and the arrangement plate 120 are arranged between the heating plate 118 and the arrangement plate 120. Arranged substantially parallel to the plate 120. Gaps are formed between the partition plate 124, the heating plate 118, and the arrangement plate 120, respectively. The partition plate 124 is made of a material having high heat resistance and high temperature oxidation resistance, such as stainless steel, or a material having high heat conductivity, such as brass. The partition plate 124, the heating plate 118, and the arrangement plate 120 may be disposed to face each other as long as a gap is formed therebetween. In addition, the partition plate 124, the heating plate 118, and the arrangement plate 120 are not limited in thickness, and may be formed in an uneven shape without being limited to a flat plate.

  The combustion chamber 126 is arranged in a space surrounded by the outer peripheral wall 122, the heating plate 118, and the arrangement plate 120. The combustion chamber 126 faces the outer peripheral end of the partition plate 124, and is formed along the outer peripheral wall 122 inside the outer peripheral wall 122. Thus, the structure which forms the combustion chamber 126 along the outer peripheral wall 122 can ensure the volume of the combustion chamber 126 enough, and can reduce a combustion load factor.

  As shown in FIG. 4A, in the main body container, the introduction path 128 and the lead-out path 130 are formed so as to overlap in the thickness direction (the direction orthogonal to the upper surface of the heating plate 118). The introduction path 128 is a space sandwiched between the placement plate 120 and the partition plate 124 with the placement plate 120 and the partition plate 124 as side walls, and is continuously disposed in the combustion chamber 126 and flows into the center of the main body container. The fuel gas is guided radially to the combustion chamber 126.

  The lead-out path 130 has a heating plate 118 and a partition plate 124 as side walls, and is continuously arranged in the combustion chamber 126, and exhaust gas is concentrated from the combustion chamber 126 to the center of the main body container and led out of the combustion heater 110. . In addition, as shown in FIG. 4A, in the main body container, the introduction path 128 and the outlet path 130 are formed so as to overlap in the thickness direction, so that the heat of the exhaust gas is transmitted through the partition plate 124, The fuel gas can be preheated.

  The support plate 132 supports the placement plate 120 from the side opposite to the introduction path 128 of the placement plate 120. Further, the arrangement plate 120 is formed of a material that is superior in high-temperature oxidation resistance than the support plate 132. In other words, even if the support plate 132 is formed of a material that is inferior in high-temperature oxidation resistance compared to the arrangement plate 120, for example, SUS304, the support plate 132 has at least rigidity to support the entire combustion heating system 100 as a casing. Good.

  By providing the arrangement plate 120 with high-temperature oxidation resistance and arranging the support plate 132 on a lower temperature side than the arrangement plate 120, the combustion heater 110 can use an inexpensive member for the support plate 132, thereby reducing the manufacturing cost. It becomes possible to reduce.

  The 1st heat insulation part 134 is continuously arrange | positioned on the surface by the side of the outer peripheral wall 122 of the combustion chamber 126, and the surface by the side of the arrangement | positioning board 120, and has heat insulation.

  With the configuration including the first heat insulating portion 134, the outer peripheral wall 122 does not directly contact the flame. Therefore, the role of ensuring high-temperature oxidation resistance in order to withstand the contact with the flame is assigned to the first heat insulating portion 134, and the role of ensuring the rigidity of the housing is assigned to the outer peripheral wall 122 (support plate 132). In addition, it is not necessary to use a member that simultaneously satisfies high-temperature oxidation resistance and rigidity, and the manufacturing cost can be reduced.

  The first heat insulating portion 134 is formed of a material that has better high-temperature oxidation resistance than the support plate 132. In other words, the support plate 132 may be formed of a material that is inferior in high-temperature oxidation resistance as compared to the first heat insulating portion 134.

  The combustion heater 110 can use an inexpensive member for the support plate 132 by providing the first heat insulation portion 134 with high temperature oxidation resistance and arranging the support plate 132 on the lower temperature side than the first heat insulation portion 134. The manufacturing cost can be reduced.

  FIG. 5 is a BB cross-sectional view of FIG. 1 in a modification. The first heat insulating portion 134 and the arrangement plate 120 in the above embodiment may be integrally formed to form the arrangement plate 220 as shown in FIG. With this configuration, it is possible to reduce the number of parts and suppress the manufacturing cost.

  Returning to FIG. 4, the second heat insulating portion 136 is sandwiched between the arrangement plate 120 and the support plate 132 and has a heat insulating property. The 3rd heat insulation part 138 is pinched between the outer peripheral wall 122 (support board 132), the 1st heat insulation part 134, and the 2nd heat insulation part 136, and has heat insulation.

  By providing the second heat insulating part 136 and the third heat insulating part 138, the temperature of the first heat insulating part 134 is maintained high, and the temperature of the flame in the combustion chamber 126 increases. As a result, the occurrence of incomplete combustion is suppressed, and the combustion heater 110 can suppress the CO emission concentration.

  The first piping part 140 is inserted into the introduction path 128 and guides the fuel gas into the combustion heater 110. Specifically, a hole 132 a having the same diameter as the outer diameter of the first piping part 140 is provided at the center of the support plate 132, and the same diameter as the inner diameter of the first piping part 140 is provided at the center of the arrangement plate 120. Holes 120a are provided. The first piping part 140 passes through the hole 132a of the support plate 132, and is connected to the inner peripheral part of the hole 120a of the arrangement plate 120 so that the inner peripheral part of the first piping part 140 continues. Further, a hole 136 a for allowing the first piping part 140 to pass therethrough is also provided at the center of the second heat insulating part 136. Here, the inner diameters of the holes 132a and 136a are equal to the outer diameter of the first piping part 140.

  The second piping part 142 is arranged inside the first piping part 140. That is, the first piping part 140 and the second piping part 142 form a double pipe. Further, the second piping part 142 is inserted into the outlet path 130 and guides the exhaust gas to the outside of the combustion heater 110. Specifically, a hole 124a having the same diameter as the outer diameter of the second piping portion 142 is provided at the center of the partition plate 124, and the second piping portion 142 is fitted to the inner peripheral portion of the hole 124a. The Further, the second piping part 142 also plays a role of transferring the heat of the exhaust gas to the fuel gas flowing through the first piping part 140.

  In addition, the second piping part 142 is provided with a bellows part 142a. The deformation due to the thermal expansion of the second piping part 142 can be absorbed by the portion of the bellows part 142a contracting in the flow path direction, and thermal fatigue and high temperature creep due to repeated heating and cooling can be suppressed.

  FIG. 6 is an assembly diagram for explaining the structure of the combustion heater 110. Here, the positional relationship of each component is demonstrated using the assembly drawing of FIG. First, the second heat insulating part 136 is inserted into the first cutout part 132 b of the support plate 132. And the 1st heat insulation part 134 is accumulated on the 2nd heat insulation part 136 from.

  As shown in FIG. 4B in which the circular portion of FIG. 4A is enlarged, the support plate 132 is provided with a notch 132c for fitting the first heat insulating part 134. The first heat insulating portion 134 is fitted into the cutout portion 132b of the support plate 132 and the cutout portion 120b of the arrangement plate 120, so that the displacement in the horizontal direction is limited. Further, the cutout portion 132b is provided large so that play can be made between the support plate 132 and the first heat insulation portion 134 when the first heat insulation portion 134 is fitted. Therefore, even if the 1st heat insulation part 134 is thermally expanded, generation | occurrence | production of the stress accompanying expansion can be avoided.

  Then, the arrangement | positioning board 120 is piled up on the 1st heat insulation part 134. FIG. As shown in FIG. 4B, the arrangement plate 120 is also provided with a notch 120 b and fits with the first heat insulating part 134. Accordingly, the horizontal displacement of the first heat insulating portion 134 is limited. Moreover, the notch part 120b of the arrangement | positioning board 120 is also provided large, and generation | occurrence | production of the stress accompanying expansion can be avoided even if the 1st heat insulation part 134 expands thermally.

  Then, the partition plates 124 are stacked, and finally, the heating plate 118 covers the whole. The outer shape of the heating plate 118 is slightly larger than that of the support plate 132. The heating plate 118 covers the support plate 132, and the folded portion 118b is folded back to be fixed to the support plate 132.

  In addition, the arrangement plate 120 is fixed to the end of the first piping part 140, while the partition plate 124 is fixed to the end of the second piping part 142 protruding from the first piping part 140, The arrangement plate 120 and the partition plate 124 are separated by the difference between the end portion of the piping portion 140 and the end portion of the second piping portion 142. At this time, a gap as a combustion chamber 126 is formed between the side surface of the partition plate 124 and the cylindrical inner peripheral surface of the outer peripheral wall 122.

  In the present embodiment, the second piping part 142 is arranged inside the first piping part 140, but is not limited to this case, and the first piping part 140 and the second piping part 142 are introduced from the heating plate 118 side. The first piping unit 140 may be disposed inside the second piping unit 142 by being inserted through the channel 128 and the outlet channel 130.

  Here, the flow of the fuel gas and the exhaust gas will be specifically described. In FIG. 4B, the white arrow indicates the fuel gas flow, the dark gray arrow indicates the exhaust gas flow, and the black arrow indicates the heat transfer. When the fuel gas is supplied to the first piping part 140, the fuel gas flows into the introduction path 128 from the central part of the arrangement plate 120 and flows toward the combustion chamber 126 while spreading radially in the horizontal direction. Then, the fuel gas collides with the outer peripheral wall 122 in the combustion chamber 126 and burns to become high-temperature exhaust gas. After the heat is transferred to the heating plate 118, the exhaust gas is transferred from the combustion chamber 126 to the second pipe through the outlet passage 130. Flows into the portion 142.

  The partition plate 124 is formed of a material that is relatively easy to conduct heat, and the heat of the exhaust gas that passes through the lead-out path 130 is transferred to the fuel gas that passes through the introduction path 128 via the partition plate 124 (heat transfer). . Here, the exhaust gas flowing through the lead-out path 130 and the fuel gas flowing through the introduction path 128 are opposed to each other (counter flow) with the partition plate 124 interposed therebetween. Preheating is possible, and high thermal efficiency can be obtained. By so-called excess enthalpy combustion, in which fuel gas is preheated in this way, combustion of the fuel gas can be stabilized, and the concentration of CO generated by incomplete combustion can be suppressed to an extremely low concentration.

  Further, in order to enable stable combustion in the combustion chamber 126, representative dimensions in a cross-sectional shape perpendicular to the flow of the fuel gas (hereinafter referred to as a flow passage cross-sectional shape) at the boundary between the introduction path 128 and the combustion chamber 126. In consideration of a flame extinguishing distance (including a flame extinguishing equivalent diameter) that does not allow a flame to pass through the introduction path 128 (a combustion reaction is not propagated toward the introduction path 128), it is preferable to set the flame extinguishing distance or less. Here, the representative dimension is a dimension determined by the cross-sectional shape of the flow channel immediately before the fuel gas flows into the combustion chamber 126. For example, when the channel cross-sectional shape is circular, the representative dimension indicates a diameter of a circular cross section, and when the channel cross-sectional shape is other than a circular shape, the representative dimension indicates a hydraulic equivalent diameter of the cross section. The hydraulic equivalent diameter D is obtained by 4 × channel cross-sectional area / wetting edge length. The wetting edge length indicates the length of the wall (arrangement plate 120, partition plate 124) portion in contact with the fuel gas in the cross section of the flow path.

  For example, if the distance between the arrangement plate 120 and the partition plate 124 is set to be equal to or less than the flame extinguishing distance, the flame does not enter the introduction path 128 and the combustion is stabilized. However, in order to make the distance between the arrangement plate 120 and the partition plate 124 equal to or less than the extinguishing distance, it is necessary to increase the surface accuracy and the mounting accuracy of the arrangement plate 120 and the partition plate 124. Therefore, in this embodiment, the distance between the arrangement plate 120 and the partition plate 124 may be made larger than the flame extinguishing distance, and the arrangement plate is located near the combustion chamber 126 on the lower surface of the partition plate 124 (on the arrangement plate 120 side). A plurality of protrusions 152 that are in contact with 120 are arranged at a predetermined interval L.

  FIG. 7 is an explanatory diagram for explaining the plurality of protrusions 152. In FIG. 7, the perspective view from CC cross section of FIG. 3 is shown. In FIG. 7, in order to facilitate understanding of the structure of the plurality of protrusions 152, portions of the protrusions 152 that are hidden by the partition plate 124 are indicated by broken lines. An arrow 154 indicates the direction of fuel gas flow. The introduction channel 128 has a channel cross-section narrowed by a plurality of protrusions 152 provided on the partition plate 124. The fuel gas flows into the combustion chamber 126 through the gap between the adjacent projections 152 as shown in the partial enlarged view of FIG. At this time, the interval L between the protrusions 152 becomes the representative dimension of the cross-sectional shape of the flow path.

Here, the flame extinguishing distance d of the fuel gas is represented by the size of the diameter of the tube wall model, and is obtained by the equation (1).
d = 2λ · Nu ^1/2 / ( Cp · ρu · Su ) (1)
In equation (1), λ is the thermal conductivity, Nu is the Nusselt number, Cp is the constant pressure specific heat, ρu is the density of the fuel gas, and Su is the combustion rate.

  The combustion heater 110 according to the present embodiment is designed so that the above-described representative dimension (interval L between the protrusions 152) is equal to or less than the extinguishing distance d, so that stable combustion is possible in the combustion chamber 126. In addition, the configuration is not limited to the configuration in which the plurality of projections 152 are provided, and one annular projection may be provided in the vicinity of the combustion chamber 126 on the lower surface of the partition plate 124. In this case, the distance between the protrusion and the arrangement plate 120 is a representative dimension. With this configuration, the representative dimension of the introduction path 128 can be set to the extinguishing distance d or less with a simpler structure.

  As described above, the combustion heater 110 transmits heat from the outlet path 130 to the inlet path 128, so that the thermal efficiency can be very high, and the exhaust gas is recovered through the second piping part 142. Will not be damaged.

  In addition, the combustion heater 110 functions as a placement plate 120 for ensuring surface accuracy and high-temperature oxidation resistance for forming the introduction passage 128, and a support plate 132 for ensuring the rigidity of the housing. Therefore, it is not necessary to use an expensive member that satisfies both high-temperature oxidation resistance and rigidity, and the support plate 132 does not need to satisfy the same surface accuracy as the placement plate 120, thereby reducing the manufacturing cost. Can do.

  Further, when the housing is integrally formed with the plurality of combustion heaters 110, the housing has a relatively large area and is required to be more rigid. However, when the arrangement plate forms a part of the housing, high surface accuracy and high-temperature oxidation resistance for forming a fuel gas introduction path are also required. For this reason, the combustion heating system requires a member that satisfies such a plurality of requirements and processing accuracy as the arrangement plate, and thus the manufacturing cost has been increased.

  In the combustion heating system 100 of this embodiment, the arrangement plate 120 does not need to serve as a housing, the support plate 132 is integrally formed in the entire combustion heating system 100, and the arrangement plate 120 is divided for each combustion heater 110. Can be arranged. Therefore, the area of the arrangement plate 120 can be kept relatively small, and it becomes easy to ensure surface accuracy and parallelism with the partition plate 124 during manufacturing. Further, even during use, even if the combustion heating system 100 has an impact or undergoes thermal deformation, since the area of the arrangement plate 120 is relatively small, the parallelism between the arrangement plate 120 and the partition plate 124 is reduced. Reduction can be suppressed.

  In the above-described embodiment, the combustion chamber 126 is formed along the outer peripheral wall 122. However, the combustion chamber 126 is not limited to this case, and the combustion chamber 126 includes the outer peripheral wall 122, the heating plate 118, and the arrangement plate 120. It suffices if it is within the enclosed space. However, in order to sufficiently secure the preheating effect of the fuel gas by the exhaust gas, the combustion chamber 126 is, for example, a space between the heating plate 118 and the partition plate 124 or a space between the partition plate 124 and the arrangement plate 120. Among these, it is desirable to be provided at any position in the space closer to the outer peripheral wall 122 than the intermediate position from the hole 120 a provided in the arrangement plate 120 to the outer peripheral wall 122.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  INDUSTRIAL APPLICABILITY The present invention can be used for a combustion heater that burns fuel and heats an object to be heated, and a combustion heating system that connects a plurality of combustion heaters.

DESCRIPTION OF SYMBOLS 110 ... Combustion heater 118 ... Heating plate 120, 220 ... Arrangement plate 122 ... Outer peripheral wall 124 ... Partition plate 126 ... Combustion chamber 128 ... Inlet path 130 ... Derivation path 132 ... Support plate 134 ... 1st heat insulation part 136 ... 2nd heat insulation Part

Claims (6)

A heating plate;
An arrangement plate disposed opposite to the heating plate;
An outer peripheral wall disposed along the outer periphery of the heating plate and the arrangement plate, and surrounding the space by the heating plate and the arrangement plate;
A partition plate disposed between the heating plate and the arrangement plate;
A combustion chamber disposed along the outer peripheral wall inside the outer peripheral wall in a space surrounded by the heating plate, the arrangement plate, and the outer peripheral wall;
A first heat insulating portion continuously disposed on a surface on the outer peripheral wall side and a surface on the arrangement plate side of the combustion chamber;
An introduction path that leads the fuel gas continuously to the combustion chamber using the arrangement plate and the partition plate as side walls;
Using the heating plate and the partition plate as side walls, the exhaust gas is led out of the combustion heater continuously from the combustion chamber to the combustion chamber, and the fuel gas is preheated by the heat of the exhaust gas through the partition plate. A lead-out path;
A support plate for supporting the placement plate from the opposite side with respect to the introduction path of the placement plate;
With
A space between the outer peripheral wall and the arrangement plate is formed with a space extending in a direction in which the fuel gas is introduced into the combustion chamber. Wherein the disposition plate, wherein with the first heat insulating member is fitted, to claim 1, characterized in that notches for forming a gap is provided between the placement plate and the first heat insulating member Combustion heater. The combustion heater according to claim 1 or 2 , wherein the first heat insulating portion is formed of a material that is superior in high-temperature oxidation resistance than the support plate. The combustion heater according to any one of claims 1 to 3 , wherein the arrangement plate is made of a material that is superior in high-temperature oxidation resistance to the support plate. The combustion heater according to any one of claims 1 to 4 , further comprising a second heat insulating portion sandwiched between the arrangement plate and the support plate and having heat insulating properties. A heating plate, an arrangement plate disposed opposite to the heating plate, an outer peripheral wall disposed along an outer periphery of the heating plate and the arrangement plate, and surrounding the space by the heating plate and the arrangement plate, and the heating A partition plate arranged between the plate and the arrangement plate, and a combustion chamber arranged along the outer peripheral wall inside the outer peripheral wall in a space surrounded by the heating plate, the arrangement plate, and the outer peripheral wall And a first heat insulating portion continuously disposed on the surface on the outer peripheral wall side and the surface on the arrangement plate side of the combustion chamber, and the fuel gas continuously in the combustion chamber with the arrangement plate and the partition plate as side walls. And the heating plate and the partition plate as side walls to guide the exhaust gas from the combustion chamber to the outside of the combustion heater and to the heat of the exhaust gas through the partition plate. A combustion heating system in which a plurality of combustion heaters including a lead-out path for preheating the fuel gas are connected,
From the opposite side to the introduction path of the arrangement plate, comprising a support plate that is a series of plate members that support the plurality of arrangement plates in a plurality of combustion heaters connected to each other,
A combustion heating system characterized in that a space extending in the direction of introduction of the fuel gas into the combustion chamber is formed between the outer peripheral wall and the arrangement plate.