Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
  • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
  • F24H1/22—Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating
  • F24H1/40—Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating with water tube or tubes
  • F24H1/43—Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating with water tube or tubes helically or spirally coiled
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
  • F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
  • F28D7/02—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being helically coiled
  • F28D7/024—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being helically coiled the conduits of only one medium being helically coiled tubes, the coils having a cylindrical configuration
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
  • F24H9/00—Details
  • F24H9/0005—Details for water heaters
  • F24H9/001—Guiding means
  • F24H9/0026—Guiding means in combustion gas channels
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F1/00—Tubular elements; Assemblies of tubular elements
  • F28F1/02—Tubular elements of cross-section which is non-circular
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F17/00—Removing ice or water from heat-exchange apparatus
  • F28F17/005—Means for draining condensates from heat exchangers, e.g. from evaporators
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
  • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
  • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
  • F28D2021/0024—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for combustion apparatus, e.g. for boilers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F2240/00—Spacing means

Definitions

• the invention lies in the field of heat exchangers, in particular those used to produce domestic hot water or water for a heating network.
• the invention relates more particularly to a heat exchanger comprising a casing, means for supplying and/or producing hot gases inside this casing to define therein a combustion chamber and at least one tube wound in a helix, arranged in this combustion chamber and inside which circulates a fluid to be heated, such as water.
• Such a heat exchanger is already known in the state of the art.
• the helical winding of the tube is arranged in such a way as to leave a small gap between its adjacent turns.
• the hot gases, produced or brought into the winding pass through the interstices, from the inside to the outside and are then evacuated to the outside of the heat exchanger by a burnt gas evacuation sleeve, provided for this purpose.
• the tube has an oblong cross-section with a front face and a rear face, flat or substantially flat, that the gap between two neighboring turns can become clogged and even clog during time, because slag, that is to say soot or unburned particles carried by the hot gases, is deposited there.
• This total or partial obstruction of certain interstices has the effect of creating an increase in the pressure of the gases circulating inside the combustion chamber, which requires increasing the speed of the fan bringing the air / fuel mixture into the burner. or bringing hot air into the room and therefore increasing the electrical consumption of this fan.
• This obstruction of certain interstices also has the effect of reducing the heat exchange surface between the fluid to be heated and the hot gases and therefore of generating a heating of the fluid circulating in the tube, which is not homogeneous over the entire length of the latter and leading to a drop in the efficiency of the heat exchanger.
• a heater provided with an integrated burner door.
• This apparatus comprises a tube inside which a fluid to be heated can circulate.
• This tube is wound in a helix so as to form a helical winding whose turns are spaced between them by a gap allowing the passage of the hot gases produced by the burner.
• These interstices are calibrated using specific bumps formed on one of the flat faces of the tube as can be seen in the figures of this document.
• a heat exchanger comprising a tube wound in a helix and arranged inside an enclosure and around a burner.
• the interstices between the turns are calibrated by a comb provided with teeth, arranged on the extrados side of the tube.
• This tube also has, on the intrados side, a plurality of wings intended to increase the contact surface and the heat transfer between the hot gases produced by the burner and the tube and therefore the fluid to be heated which circulates therein. These wings are formed at the intrados ends of the tube (on the short sides thereof).
• An object of the invention is therefore to propose a heat exchanger making it possible to solve the aforementioned problems and in particular to limit the fouling of the interstices between two neighboring turns of the tube of this exchanger.
• the invention relates to a heat exchanger comprising:
• At least one tube made of a thermally good conductive material and inside which a fluid to be heated, such as water, can circulate, this tube being wound helically so as to form a helical winding with a longitudinal axis X-X', this helical winding being arranged inside said casing,
• said at least one tube has on its front face and/or its rear face, a shoulder, this shoulder extends from the intrados side of the tube towards its extrados side, over part of the height of the cross section of this tube and this shoulder also extends either over the entire length of said at least one tube located in said combustion chamber, or over the entire length of said at least one tube located in said combustion chamber exception of the first or the last turn of the helical winding, and each gap between two neighboring turns is calibrated either using a tooth of a comb introduced into the gap between two turns, on the side extrados of the tube, either by means of several projecting elements, such as bosses, formed on the front face and/or on the rear face of said at least one tube, each projecting element formed on a turn of the tube being supported respectively against the back side e t/or the front face of the adjacent turn, so that the shoulder makes it possible to recover the soot and the slag entrained in the hot gases which cross the interstices.
• This shoulder makes it possible to recover the soot or slag resulting from the combustion of gases by the burner, while keeping the gap between two neighboring turns clear.
• the hot gases can thus continue to cross this interstice and to heat the water circulating in the helical winding.
• This shoulder therefore makes it possible to delay the rate of fouling of the turns, to limit the increase in pressure in the combustion chamber, not to generate excess electrical consumption of the exchanger, to maintain the efficiency of the exchanger and to delay and space out the maintenance/cleaning operations carried out on the heat exchanger tube.
• the shoulder extends over a height, measured from the lower surface, which measures up to approximately one third of the height of the straight section of the tube.
• this discoid deflector is mounted inside the helical winding in a gas-tight manner, this discoid deflector provides, inside the casing, a condensation chamber which extends between said discoid deflector and the bottom of the the casing and a combustion chamber which extends between said discoid deflector and a front of the casing on which is mounted a door carrying said means for supplying and/or producing hot gases and the shoulder is formed exclusively on the tube or tubes or the portion of the tube which is positioned in the combustion chamber.
• the gap between the adjacent turns is calibrated using several projecting elements, such as bosses, formed on the front face and/or on the rear face of said at least one tube, each projecting element formed on a turn of the tube resting respectively against the rear face and/or the front face of the adjacent turn and in that each projecting element is formed on the part of the front face and/or the rear face which does not include the shoulder.
• projecting elements such as bosses, formed on the front face and/or on the rear face of said at least one tube, each projecting element formed on a turn of the tube resting respectively against the rear face and/or the front face of the adjacent turn and in that each projecting element is formed on the part of the front face and/or the rear face which does not include the shoulder.
• the gap between the adjacent turns is calibrated using several projecting elements, such as bosses, formed on the front face or on the rear face of said at least one tube, in that the projecting elements and the shoulder are formed on opposite faces of the tube and in that the projecting elements bear against the portion of the face of the tube which does not include the shoulder.
• projecting elements such as bosses
• FIG. 2 is a perspective view of part of a heat exchanger tube according to the invention.
• FIG. 3 is a longitudinal sectional view of a condensation heat exchanger according to the invention.
• FIG. 4 is a perspective view of a comb
• FIG. 5 is a detail view of a cross section of three turns of the tube according to the invention, the section being made at the level of the bosses;
• FIG. 6 is a detail view of a cross section of three turns of the tube according to the invention, the section being made at a point of the tube free of bosses;
• FIG. 7 is a detail view of a cross section of three turns of the tube according to another embodiment of the invention.
• FIG. 1 shows a heat exchanger 1 comprising only a combustion chamber. In this figure, it is shown in its normal position of use.
• This heat exchanger 1 comprises a casing 2, means for supplying and/or producing hot gases inside said casing and at least one tube 4, inside which circulates the fluid to be heated, in particular the water.
• a pump not visible in the figures ensures this circulation of water.
• the casing 2 has a generally tubular shape and extends along a longitudinal axis X-X'. In known manner, it has at its upper part a sleeve 21 for the evacuation of the burnt gases and at its lower part, an outlet orifice connected to an evacuation conduit 22 for the condensates.
• the casing 2 is closed at its rear end by a bottom 23, equipped on its internal face with a disc 230 made of thermally insulating material.
• a facade 24 is fixed to the front of the envelope 2. It comprises a central opening, able to be closed by a door 25.
• the tube 4 is made of a thermally good conductive material, such as metal. It is wound on itself in a helix, so as to form a helical winding 40 and it is placed inside the casing 2 so that its longitudinal axis X-X' coincides with the longitudinal axis X-X' of envelope 2.
• the hot gas production means are preferably a burner 3, for example a gas or oil burner.
• This burner 3 is preferably tubular in shape, and it is arranged inside the casing 2 and inside the winding 40, so that its longitudinal axis X-X' coincides with the axis longitudinal X-X' of the envelope 2.
• the burner 3 is fixed on the internal face of the door 25.
• the hot gas supply means (not shown in the figures) comprise a burner arranged outside the exchanger and a fan fixed to the door 25 to introduce the hot gases inside the casing 2, in the helical winding 40.
• the space which extends inside the winding 40 thus constitutes a combustion chamber 26.
• the tube 4 has two ends forming an inlet mouth and an outlet mouth, from which the fluid to be heated is respectively introduced and extracted.
• One of these mouthpieces 400 is visible in Figure 2.
• the tube 4 has an oblong cross section, which can be oval or rectangular or even rectangular with small sides which can be projecting and curved (as shown in the figures) or even being projecting and V-shaped.
• the tube 4 thus has a front face 41 and a rear face 42 that are opposite each other.
• front face designates the face facing the front of the exchanger, that is to say towards the facade 24
• rear face designates the face facing the rear of the exchanger, that is to say towards the bottom 23.
• the tube 4 has an intrados side 43, oriented towards the axis X-X' and towards the combustion chamber 26 (or towards the burner 3 when the latter is present) and an opposite extrados side 44, oriented towards the envelope 2.
• intrados 43 and extrados 44 sides correspond to the short sides of the tube 4.
• the front 41 and rear 42 faces are flat and parallel to each other.
• these front 41 and rear 42 faces may not be strictly flat but substantially flat (for example slightly curved).
• the winding of the tube 4 is made so that the major axis Y-Y' of the cross section of the tube is perpendicular to the longitudinal axis X-X' of the helical winding 40.
• this major axis Y-Y' could also be slightly inclined with respect to the longitudinal axis X-X' of the helical winding 40 without departing from the scope of the invention.
• the helical winding 40 has a series of neighboring turns and there is a gap
• the hot gases leave the combustion chamber 26 passing through the interstices 45, from the inside to the outside, as symbolized by the arrows i. In doing so, they heat the walls of the tube 4 and in particular the front faces 41 and 42 and therefore the water which circulates in this tube.
• the gases are then evacuated to the outside through the sleeve 21, (see arrows ii).
• the tube 4 has on its front face 41 and / or its rear face 42, a shoulder 46.
• This shoulder 46 is on its front face 41 and / or its rear face 42.
• this shoulder 46 extends over a height H2 (measured from the lower surface 43) less than H1.
• H2 measured from the lower surface 43
• the presence of the shoulder 46 causes the outer width L2 of the cross section of the tube 4 taken at the level of the shoulder 46 to be less than the outer width L1 of the cross section of the tube 4 taken in the part of the tube where there is no shoulder 46.
• the height H2 measures up to approximately one third of the height H1.
• the shoulder 46 can extend over the entire length of the tube 4. Preferably, and as can be seen in Figure 2, this shoulder 46 is continuous.
• the first turn of the winding applied against the facade 24 does not have this shoulder 46. It could be the same on the last turn of the winding applied against the bottom 23 and the plate 230, in the case where the shoulder 46 is provided on the rear face 42.
• the shoulder 46 makes it possible to create a housing for recovering the soot and slag which are entrained in the hot gases which pass through the interstices 45.
• the gap (or the width) between two neighboring turns, measured at the level of this shoulder 46 is referenced E1 when there is a shoulder 46 only on the front face 41 (see FIGS. 5 and 6) or only on the rear face 42 and is referenced E2 when there is a shoulder 46 on the front face 41 and a shoulder 46 on the rear face 42 (see Figure 7).
• This gap E1, E2 is therefore wider than the gap (or width) E3 between two neighboring turns, measured where there is no shoulder 46, which allows both to trap the slag in the shoulder 46 and to keep room for the passage of hot gases.
• the winding 40 therefore clogs up less quickly, which makes it possible to reduce the frequency of cleaning operations.
• the interstices 45 between two neighboring turns are advantageously calibrated so as to be all identical and thus that the flows of hot gases circulating therein are homogeneous and that the heating of the fluid is regular over the entire length of the tube.
• the interstices 45 can be calibrated using one or more combs 5, such as that shown for example in Figure 4.
• This comb 5 has a plurality of teeth 50 parallel to each other.
• This comb 5 is arranged with respect to the winding 40, so that each of its teeth 50 is introduced into a gap 45, on the extrados side 44 of the tube 4, in order to calibrate this gap 45.
• Each tooth 50 is thus in contact of the front face 41 of a turn of the tube 4 and of the rear face 42 of the neighboring turn of the tube 4.
• the teeth 50 do not extend to the level of the shoulder 46.
• the interstices 45 can be calibrated using projecting elements, such as bosses 47 (corrugations) formed on the front face 41 of the tube 4, (as represented in the figures 1, 2 and 5) or on the rear face 42 (not visible in the figures). These bosses are preferably distributed uniformly over the entire length of the tube to obtain interstices 45 of constant width.
• Each projecting element formed on the front face 41 and/or on the rear face 42 of the tube 4 rests respectively against the rear face 42 and/or the front face 41 of the adjacent turn.
• bosses 47 and the shoulder 46 are made on the same front or rear face of the tube 4, for example on the front face 41 as shown in FIG. 2, then the bosses 47 are advantageously made on the portion referenced 49 from the side of the tube which does not include the shoulder 46, (see also Figure 5).
• the projecting elements such as the bosses 47
• the shoulder 46 are made on opposite faces of the tube 4 (for example the shoulder 46 on the front face 41 and the projecting elements on the rear face 42 or the reverse), then the protruding elements bear against the portion 49 of the face of the tube which does not include the shoulder 46.
• the gas evacuation sleeve 21 is connected to the condensation chamber 27.
• the deflector 6 comprises a disc 61 of thermally insulating material, carried by a thin sheet metal frame 62, provided with a radial peripheral flange 63.
• the deflector 6 is mounted inside the winding 40 of the tube 4, so that its flange 63 is inserted and positioned in a gas-tight manner, in the interstice 45 existing between the last turn of the tube 4 located in the combustion chamber 26 and the first turn of the tube 4 located in the condensation chamber 27.
• the shoulder 46 is formed only on the turns of the tube 4 which are in the combustion chamber 26 and not on the turns of the tube which are in the condensation chamber 27.
• the hot gases produced by the burner 3 leave the combustion chamber 26 passing through the interstices 45 formed in the turns of the tube 4 which are in this combustion chamber 26, (see the arrows i ) and the slag is trapped in the shoulder 46. Then, the hot gases abut against the casing 2 and are guided towards the extrados side 44 of the turns of the tube 4 located in the condensation chamber 27 (see the arrows iii ). These hot gases then cross the interstices 45 formed between the turns, this time from the outside inwards, in the direction of the condensation chamber 27 (see arrows iv). These hot gases then no longer contain slag, so that the shoulder 46 is not necessary.
• I ' comprises a unique 4 tube wound in a helical.
• part of the turns of the single tube 4 extends into the combustion chamber 26 and the other part of the turns into the condensation chamber 27.
• condensation heat exchanger 1' it is possible to have one or more tubes 4 in the combustion chamber 26 and one or more tubes 4 in the condensation chamber 27.
• the tube 4 can be manufactured by different processes. Two non-limiting examples of manufacturing methods are given below.
• Such a method has the advantage of being able to vary the profile of the section of the tube 4 all along the helical winding 40 and in particular of forming the shoulder 46 only over a certain part of the length of the tube 4.
• this method makes it possible to create the shoulder 46 only on the turns which are in the combustion chamber 26, in the case of the condensation heat exchanger 1 '.
• this process also makes it possible to have a tube whose faces of the first turn and of the last turn are flat, which makes it possible to simplify the design of the bottom and the front of the exchanger.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Geometry (AREA)
• Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
• Details Of Fluid Heaters (AREA)

Applications Claiming Priority (2)

Publications (3)

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Family Applications (1)

Country Status (8)

Family Cites Families (13)

• 2021
  • 2021-07-16 FR FR2107688A patent/FR3125326B1/fr active Active
• 2022
  • 2022-07-15 CA CA3221971A patent/CA3221971A1/fr active Pending
  • 2022-07-15 CN CN202280049131.1A patent/CN117642594A/zh active Pending
  • 2022-07-15 US US18/578,991 patent/US12474123B2/en active Active
  • 2022-07-15 WO PCT/EP2022/069914 patent/WO2023285680A1/fr not_active Ceased
  • 2022-07-15 EP EP22741788.8A patent/EP4370855B1/de active Active
  • 2022-07-15 JP JP2024502214A patent/JP2024525838A/ja active Pending
  • 2022-07-15 KR KR1020247002632A patent/KR20240036012A/ko active Pending

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