EP0075811A1 - Apparatus for heating a liquid or gaseous medium - Google Patents

Apparatus for heating a liquid or gaseous medium Download PDF

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Publication number
EP0075811A1
EP0075811A1 EP82108626A EP82108626A EP0075811A1 EP 0075811 A1 EP0075811 A1 EP 0075811A1 EP 82108626 A EP82108626 A EP 82108626A EP 82108626 A EP82108626 A EP 82108626A EP 0075811 A1 EP0075811 A1 EP 0075811A1
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EP
European Patent Office
Prior art keywords
rings
medium
spirals
coils
channels
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP82108626A
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German (de)
French (fr)
Inventor
Ingemar Ing. Greis
Artur Ing. Östlund
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ABB Norden Holding AB
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ASEA AB
Stal Laval Apparat AB
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Publication date
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Publication of EP0075811A1 publication Critical patent/EP0075811A1/en
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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/02—Induction heating
    • H05B6/10—Induction heating apparatus, other than furnaces, for specific applications
    • H05B6/105—Induction heating apparatus, other than furnaces, for specific applications using a susceptor
    • H05B6/108—Induction heating apparatus, other than furnaces, for specific applications using a susceptor for heating a fluid
    • 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
    • F24H1/10—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium
    • F24H1/101—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium using electric energy supply

Definitions

  • the invention relates to a device for heating a liquid or gaseous medium according to the preamble of claim 1.
  • the invention is based on the object of developing a device of the type mentioned at the beginning which in a simple manner enables effective transfer of the heat to the flowing medium, which can have a large volume at low pressures.
  • the invention provides a simple, effective and not very space-consuming heating device that is attractive for many areas of application, such as, for example, as an air preheater for scrap heating.
  • the invention is an inductive heating device which is particularly suitable for air or other fluid media with a relatively low pressure but a large volume.
  • gases for the heating of which the device can advantageously be used, include water vapor, CO and N 2 .
  • induction currents are generated in the rings or spirals, which generate heat in the electrical circuits consisting of the rings or spirals and possibly also of the metal cylinders delimiting the channels.
  • This heat is given off to the medium flowing through it, for example air.
  • the passage path of the medium through the heating device can be designed as a labyrinth channel system with channels concentric with one another, through which the medium flows in sequence, this through the rings or spirals arranged in or on the channels or around the channels and possibly also channel-separating cylinder is heated. The heating of the medium takes place through its contact with the individual heated metal surfaces.
  • Medium to be heated e.g. Air, at low temperature, supplied and passed into a gas-tight outer cylinder 16 (Fig. 1).
  • One or more induction coils 2 are arranged around the gas-tight outer shell 16 and are fed with alternating current from the mains frequency or another frequency.
  • the outer cylinder 16 can be part of a labyrinth channel system with two or more channels 3, 4 arranged concentrically with one another for the medium.
  • the medium flows through these passages 3, 4 in sequence and continues to flow into a line 5, the medium being heated to a high temperature as it flows through.
  • These are essentially relatively large volume flows and low pressures.
  • another fluid medium such as water vapor, CO, N 2, etc.
  • the channels are delimited from one another by sheet metal cylinders 6 or other metal cylinders, which are expediently gas-tight.
  • Metallic elements 7 in the form of rings or spirals are arranged axially one behind the other in the channels 3, 4.
  • rings arranged axially one behind the other, concentric to the tube axis, which can also be arranged in several concentric layers, one or more per channel 3, 4 (see also FIG. 3).
  • the plate cylinders 6 can be provided with flanges or other area-enlarging parts become what also applies to the rings 7.
  • the rings 7 can each be individually or several together as electrically closed circles, possibly together with short-circuit devices, not shown.
  • the closed metallic circles can also be formed from one or more spirals with short-circuit devices, not shown.
  • the circles can be arranged concentrically around one another and / or axially one behind the other.
  • the coil can be one coil or several coils. With a coil, the supply is usually single-phase, which was also the case with several coils, but several coils can also be supplied with multiple phases, e.g. with one phase per coil.
  • the coils can be arranged axially one behind the other for the channels for the medium or laterally, for example in the case of several heat exchangers, where one E-phase coil per phase is used.
  • the induction coil (s) 2 When the induction coil (s) 2 are fed, currents are generated by induction in the rings or in the spirals, which lie in the electrically closed circles, which heat the parts through which current flows. Care is taken to ensure that each ring or spiral has a certain electrical resistance.
  • the above-mentioned short-circuit elements serve to form one or more closed electrical circuits.
  • the plate cylinders 6 are also heated inductively and thus contribute to the power transmission. Low voltages and relatively high currents occur during this heating process.
  • the outer cylinder 16 preferably consists of electrically non-conductive material, expediently of non-metallic material, such as ceramic material, plastic, glass, etc., this material preferably being gas-tight.
  • the outer cylinder can also consist of austenitic sheet metal, which also applies to the other cylinders 6.
  • the cylinders can either look like this be performed that they form an electrical short circuit, or or partially so that they are not electrically short-circuited, which can be achieved for example by a combination of the cylinders made of sheet metal and ceramic.
  • the air flows with increasing heating over the metallic elements 7 consisting of rings or spirals. These can be hollow tubes, solid rods, metal strips or the like, which are shaped into rings or spirals and / or welded together.
  • the material used for the outer cylinder 16 and the plate cylinder 6 should preferably be temperature-resistant and non-ferromagnetic. Due to different amounts of material in the rings 7, the power implemented in the rings can be changed from ring to ring. With a suitable composition it can be achieved that maximum heat transfer is achieved with minimal use of materials.
  • the metallic elements 7 can be provided with turbulence-forming elements. (See Fig. 3 in this regard).
  • Air preheaters for scrap heating and / or for phase compensation can be mentioned as a preferred field of application for the aforementioned embodiment of the invention.
  • the rings 9, 10 ( Figure 2) as well as the plate cylinders 12, 13 and the outer shell 16 are arranged so that a labyrinth channel system according to Figure 1 is formed, but other types of channel arrangements can also occur.
  • the rings or spirals are heated inductively and thereby heat the air flowing in the direction of the arrows 11 in FIG. 2.
  • the outer shell 16 can also be provided with flanges or other area-enlarging elements.
  • the outer shell 16 is advantageously made of ceramic material.
  • the heat transfer to the air depends on the product of the heat transfer coefficient ⁇ , the heat transfer surface A and the temperature difference ⁇ t.
  • the amount of heat transferred is ⁇ .
  • the heat transfer coefficient ⁇ can be increased further by arrangements for increasing the turbulence of the medium, such as, for example, by changing certain dimensions of the rings 7.
  • the rings have a relatively large surface A which is in contact with the air flow (see FIG. 3).
  • the heat-transferring contact area A can also be slightly increased by providing the rings with flanges.
  • Another great advantage is that the temperature difference ⁇ t, which is limited by the maximum permissible material temperature and the air temperature rising due to the heating, can be individually influenced for each ring. As already mentioned, this takes place, for example, in that the amount of material contained in the individual rings is dimensioned differently. This changes the electrical power converted into heat in the ring in question. A maximum value for At and therefore a maximum heat transfer can therefore be achieved for each ring.
  • FIG. 3 shows in more detail the path of the air flowing through the device (see arrows 11) and the arrangement of the flow-separating sheet metal cylinders 12, 13 which can be inductively heated together with the rings 7.
  • the rings By placing the rings differently (see, for example, the reference numerals 8 and 14 on the right in FIG. 3) and by different amounts of material in the individual rings (see the pipes 15 and 16 of different thicknesses on the right in FIG. 3), optimal heat transfer can be achieved.
  • the turbulence can also be caused by shifting individual rings, for example every tenth Ring (see the ring 17 in Fig. 3) can be increased. Other inserts, not shown, which increase the turbulence can also be provided.
  • Central tubes are those that run within the individual induction coils. It goes without saying that these do not have to run exactly concentrically in relation to the coil. Some side shift is harmless and can be used to allow proper placement of the rings, spirals, etc.
  • the various turbulence-generating elements can be arranged separately, that is to say separately from the rings or spirals, or on the rings or spirals.
  • a change in the position of the different rings can be provided over the entire length of the heating device or over certain parts thereof.

Abstract

Induktiv arbeitende Vorrichtung zur Erwärmung eines flüssigen oder gasförmigen Mediums wie z.B. Luft oder Wasser, bei der um eine oder mehrere zentrale Leitungen (1) für das zu erwärmende Medium eine oder mehrere elektrische Induktionsspulen (2) angeordnet sind. Das Medium durchströmt dabei ein Kanalsystem in Labyrinthform, das aus einem äußeren Kanal (3), einem oder mehreren zu diesem konzentrischen inneren Kanälen (4) und einem Innenrohr (5) besteht. In mindestens einem dieser Kanäle sind metallische Ringe (7) oder Spiralen angeordnet, die elektrische Kurzschlußkreise bilden und die bei Speisung der Induktionsspulen (2) erhitzt werden. Sie geben ihre Wärme an das über sie hinwegstreichende Medium ab.Inductive device for heating a liquid or gaseous medium, e.g. Air or water in which one or more electrical induction coils (2) are arranged around one or more central lines (1) for the medium to be heated. The medium flows through a channel system in the form of a labyrinth, which consists of an outer channel (3), one or more inner channels (4) concentric with this and an inner tube (5). Metallic rings (7) or spirals are arranged in at least one of these channels, which form electrical short-circuit circuits and which are heated when the induction coils (2) are supplied. They give off their heat to the medium sweeping over them.

Description

Die Erfindung betrifft eine Vorrichtung zur Erwärmung eines flüssigen oder gasförmigen Mediums gemäß dem Oberbegriff des Anspruches 1.The invention relates to a device for heating a liquid or gaseous medium according to the preamble of claim 1.

Es ist bereits bekannt, Metall dadurch auf induktivem Wege zu erhitzen, daß das Metall in ein magnetisches Wechselfeld gebracht wird. Bei der Anwendung dieses Prinzips auf die Erwärmung von Gasen und Flüssigkeiten, beispielsweise im Zusammenhang mit der Erhitzung von Schrott, stellt sich das Problem, einen guten Wärmeübergang auf die zu erwärmenden Medien zu erzielen. Ein weiteres Problem besteht darin, eine hinsichtlich der Produktion geeignete einfache Vorrichtung für die Wärmeübertragung zu schaffen. Es ist dazu notwendig, Medien mit verhältnismäßig großen Volumenflüssen und niedrigen Drücken zu erhitzen.It is already known to heat metal by induction by bringing the metal into an alternating magnetic field. When applying this principle to the heating of gases and liquids, for example in connection with the heating of scrap, the problem arises of achieving good heat transfer to the media to be heated. Another problem is to provide a simple heat transfer device suitable for production. It is necessary to heat media with relatively large volume flows and low pressures.

Der Erfindung liegt die Aufgabe zugrunde, eine Vorrichtung der eingangs genannten Art zu entwickeln, die auf einfache Weise eine wirksame Übertragung der Wärme auf das strömende Medium ermöglicht, welches ein großes Volumen bei niedrigen Drücken haben kann.The invention is based on the object of developing a device of the type mentioned at the beginning which in a simple manner enables effective transfer of the heat to the flowing medium, which can have a large volume at low pressures.

Zur Lösung dieser Aufgabe wird eine Vorrichtung nach dem Oberbegriff des Anspruches 1 vorgeschlagen, die erfindungsgemäß die im kennzeichnenden Teil des Anspruches 1 genannten Merkmale hat.To solve this problem, a device is proposed according to the preamble of claim 1, which according to the invention has the features mentioned in the characterizing part of claim 1.

Vorteilhafte Weiterbildungen der Erfindung sind in den Unteransprüchen genannt.Advantageous developments of the invention are mentioned in the subclaims.

Durch die Erfindung erhält man eine einfache, wirksame und nicht sehr platzraubende Heizvorrichtung, die für viele Anwendungsgebiete attraktiv ist, wie z.B. als Luftvorwärmer bei der Schrotterhitzung. Bei der Erfindung handelt es sich um eine induktive Heizvorrichtung, die besonders für Luft oder andere fluide Medien mit verhältnismäßig niedrigem Druck aber großem Volumen geeignet ist. Als andere Gase, zu deren Erhitzung die Vorrichtung vorteilhaft anwendbar ist, sind insbesondere zu nennen Wasserdampf, CO und N2. Auch die die Kanäle gegeneinander abgrenzenden Zylinder, die zweckmäßigerweise aus Metall bestehen, z.B. Blechzylinder, tragen zu der Leistungsübertragung bei, da auch in diesen elektrische Ströme durch Induktion erzeugt werden. Dabei fließen verhältnismäßig hohe Ströme bei niedrigen treibenden elektrischen Spannungen.The invention provides a simple, effective and not very space-consuming heating device that is attractive for many areas of application, such as, for example, as an air preheater for scrap heating. The invention is an inductive heating device which is particularly suitable for air or other fluid media with a relatively low pressure but a large volume. Other gases, for the heating of which the device can advantageously be used, include water vapor, CO and N 2 . The cylinders delimiting the channels from one another, which suitably consist of metal, for example sheet metal cylinders, also contribute to the power transmission, since electrical currents are also generated in them by induction. Relatively high currents flow at low driving electrical voltages.

In den Ringen oder Spiralen werden bei der Speisung der Induktionsspulen durch Induktion Ströme erzeugt, welche Wärme in den aus den Ringen oder Spiralen und eventuell auch aus den die Kanäle abgrenzenden Metallzylindern bestehenden elektrischen Kreise erzeugen. Diese Wärme Wird an das hindurchströmende Medium, beispielsweise Luft, abgegeben. Der Durchtrittsweg des Mediums durch die Heizvorrichtung kann als Labyrinthkanalsystem mit untereinander konzentrischen Kanälen ausgebildet sein, die der Reihe nach von dem Medium durchströmt werden, wobei dieses durch die in oder an den Kanälen bzw. um die Kanäle herum angeordneten Ringe oder Spiralen und eventuell auch die kanaltrennenden Zylinder erhitzt wird. Die Erwärmung des Mediums erfolgt dabei durch seinen Kontakt mit den einzelnen erhitzten Metallflächen.When induction coils are fed, induction currents are generated in the rings or spirals, which generate heat in the electrical circuits consisting of the rings or spirals and possibly also of the metal cylinders delimiting the channels. This heat is given off to the medium flowing through it, for example air. The passage path of the medium through the heating device can be designed as a labyrinth channel system with channels concentric with one another, through which the medium flows in sequence, this through the rings or spirals arranged in or on the channels or around the channels and possibly also channel-separating cylinder is heated. The heating of the medium takes place through its contact with the individual heated metal surfaces.

Anhand der in den Figuren gezeigten Ausführungsbeispiele soll die Erfindung näher erläutert werden. Es zeigen

  • Fig. 1 ein Ausführungsbeispiel einer Vorrichtung gemäß der Erfindung als Luftvorwärmer,
  • Fig. 2 den Luftvorwärmer gemäß Fig. 1 von oben gesehen,
  • Fig. 3 den Luftvorwärmer mit weiteren Detailausführungen.
The invention will be explained in more detail with reference to the exemplary embodiments shown in the figures. Show it
  • 1 shows an embodiment of a device according to the invention as an air preheater,
  • 2 seen the air preheater of FIG. 1 from above,
  • Fig. 3 shows the air preheater with further details.

Über eine Leitung 1 wird zu erhitzendes Medium, z.B. Luft, mit niedriger Temperatur, zugeführt und in einen gasdichten Außenzylinder 16 (Fig. 1) hineingeleitet. Um die gasdichte Außenhülle 16 herum sind eine oder mehrere Induktionsspulen 2 angeordnet, die mit Wechselstrom von Netzfrequenz oder einer anderen Frequenz gespeist werden.Medium to be heated, e.g. Air, at low temperature, supplied and passed into a gas-tight outer cylinder 16 (Fig. 1). One or more induction coils 2 are arranged around the gas-tight outer shell 16 and are fed with alternating current from the mains frequency or another frequency.

Der Außenzylinder 16 kann Teil eines Labyrinthkanalsystems mit zwei oder mehreren untereinander konzentrisch angeordneten Kanälen 3, 4 für das Medium sein. Das Medium durchströmt diese Passagen 3, 4 der Reihe nach und strömt weiter in eine Leitung 5, wobei das Medium während seines Durchströmens auf eine hohe Temperatur erhitzt wird. Es handelt sich hier im wesentlichen um verhältnismäßig große Volumenflüsse und niedrige Drücke. Statt Luft kann ein anderes fluides Medium, wie Wasserdampf, C0, N2 usw, erhitzt werden. Die Kanäle werden durch Blechzylinder 6 oder andere Metallzylinder, die zweckmäßigerweise gasdicht sind, gegeneinander abgegrenzt. Axial hintereinander sind in den Kanälen 3, 4 metallische Elemente 7 in Form von Ringen oder Spiralen angeordnet. Im gezeigten Fall handelt es sich um axial hintereinander angeordnete, zur Rohrachse konzentrische Ringe, die auch in mehreren konzentrischen Schichten, eine oder mehrere je Kanal 3, 4,angeordnet sein können (Siehe auch Fig. 3). Die Blechzylinder 6 können mit Flanschen oder anderen flächenvergrößernden Teilen versehen werden, was auch für die Ringe 7 gilt.The outer cylinder 16 can be part of a labyrinth channel system with two or more channels 3, 4 arranged concentrically with one another for the medium. The medium flows through these passages 3, 4 in sequence and continues to flow into a line 5, the medium being heated to a high temperature as it flows through. These are essentially relatively large volume flows and low pressures. Instead of air, another fluid medium, such as water vapor, CO, N 2, etc., can be heated. The channels are delimited from one another by sheet metal cylinders 6 or other metal cylinders, which are expediently gas-tight. Metallic elements 7 in the form of rings or spirals are arranged axially one behind the other in the channels 3, 4. In the case shown, there are rings arranged axially one behind the other, concentric to the tube axis, which can also be arranged in several concentric layers, one or more per channel 3, 4 (see also FIG. 3). The plate cylinders 6 can be provided with flanges or other area-enlarging parts become what also applies to the rings 7.

Die Ringe 7 können jeder für sich oder mehrere zusammen als elektrisch geschlossene Kreise, eventuell zusammen mit nicht gezeigten Kurzschlußvorrichtungen ausgebildet werden. Die geschlossenen metallischen Kreise können auch aus einer oder mehreren Spiralen mit nicht dargestellten Kurzschlußvorrichtungen ausgebildet sein. Die Kreise können konzentrisch umeinander und/oder axial hintereinander angeordnet werden. Bei der Spule kann es sich um eine Spule oder um mehrere Spulen handeln. Bei einer Spule ist die Speisung normalerweise einphasig, was auch bei mehreren Spulen der Fall sein kam.Mehrere Spulen können aber auch mehrphasig gespeist werden, z.B. mit einer Phase pro Spule. Die Spulen können axial hintereinander um die Kanäle für das Medium oder seitlich voneinander, beispielsweise bei mehreren Wärmeaustauschern, wo man eine E-inphasenspule pro Phase verwendet, angeordnet werden.The rings 7 can each be individually or several together as electrically closed circles, possibly together with short-circuit devices, not shown. The closed metallic circles can also be formed from one or more spirals with short-circuit devices, not shown. The circles can be arranged concentrically around one another and / or axially one behind the other. The coil can be one coil or several coils. With a coil, the supply is usually single-phase, which was also the case with several coils, but several coils can also be supplied with multiple phases, e.g. with one phase per coil. The coils can be arranged axially one behind the other for the channels for the medium or laterally, for example in the case of several heat exchangers, where one E-phase coil per phase is used.

Bei der Speisung der Induktionsspule(n) 2 werden durch Induktion Ströme in den Ringen oder in den Spiralen, die in den elektrisch geschlossenen Kreisen liegen, erzeugt, welche die stromdurchflossenen Teile erhitzen. Hierbei wird darauf geachtet, daß jeder Ring bzw. jede Spirale einen gewissen elektrischen Widerstand hat. Die obengenannten, in den Figuren nicht dargestellte Kurzschlußelemente dienen zur Bildung eines oder mehrerer geschlossener elektrischer Kreise. Auch die Blechzylinder 6 werden induktiv erwärmt und tragen somit zur Leistungsübertragung bei. Bei diesem Erhitzungsvorgang treten niedrige Spannungen und verhältnismäßig hohe Ströme auf. Der Außenzylinder 16 besteht vorzugsweise aus elektrisch nicht leitendem Material, zweckmäßigerweise aus nicht metallischem Material, wie z.B. keramischem Material, Kunststoff, Glas usw., wobei dieses Material vorzugsweise gasdicht ist. Der Außenzylinder kann auch aus austenitischem Blech bestehen, was auch für die übrigen Zylinder 6 gilt. Die Zylinder können entweder so ausgeführt werden, daß sie einen elektrischen Kurzschlußkreis bilden, oder bzw. teilweise'so, daß sie nicht elektrisch kurzgeschlossen sind, was beispielsweise durch eine Kombination der Zylinder aus Blech und Keramik erreicht werden kann.When the induction coil (s) 2 are fed, currents are generated by induction in the rings or in the spirals, which lie in the electrically closed circles, which heat the parts through which current flows. Care is taken to ensure that each ring or spiral has a certain electrical resistance. The above-mentioned short-circuit elements, not shown in the figures, serve to form one or more closed electrical circuits. The plate cylinders 6 are also heated inductively and thus contribute to the power transmission. Low voltages and relatively high currents occur during this heating process. The outer cylinder 16 preferably consists of electrically non-conductive material, expediently of non-metallic material, such as ceramic material, plastic, glass, etc., this material preferably being gas-tight. The outer cylinder can also consist of austenitic sheet metal, which also applies to the other cylinders 6. The cylinders can either look like this be performed that they form an electrical short circuit, or or partially so that they are not electrically short-circuited, which can be achieved for example by a combination of the cylinders made of sheet metal and ceramic.

Die Luft strömt unter zunehmender Erwärmung über die aus Ringen oder Spiralen bestehenden metallischen Elemente 7. Bei diesen kann es sich um hohle Rohre, volle Stangen, Blechbänder o. dgl. handeln, die zu Ringen oder Spiralen geformt und/oder zusammengeschweißt sind. Das für den Außenzylinder 16 und die Blechzylinder 6 verwendete Material soll vorzugsweise temperaturbeständig und nichtferromagnetisch sein. Durch unterschiedliche Materialmengen in den Ringen 7 kann die in den Ringen umgesetzte Leistung von Ring zu Ring verändert werden. Durch geeignete Zusammensetzung kann man hierbei erreichen, daß eine maximale Wärmeübertragung mit minimalem Materialeinsatz erreicht wird. Die metallischen Elemente 7 können mit turbulenzbildenden Elementen versehen werden. (Siehe diesbezüglich Fig. 3).The air flows with increasing heating over the metallic elements 7 consisting of rings or spirals. These can be hollow tubes, solid rods, metal strips or the like, which are shaped into rings or spirals and / or welded together. The material used for the outer cylinder 16 and the plate cylinder 6 should preferably be temperature-resistant and non-ferromagnetic. Due to different amounts of material in the rings 7, the power implemented in the rings can be changed from ring to ring. With a suitable composition it can be achieved that maximum heat transfer is achieved with minimal use of materials. The metallic elements 7 can be provided with turbulence-forming elements. (See Fig. 3 in this regard).

Als bevorzugtes Anwendungsgebiet für die vorgenannte Ausführungsform der Erfindung können Luftvorwärmer für die Schrotterhitzung und/oder für die Phasenkompensation genannt werden. Die Ringe 9, 10 (Figur 2) wie auch die Blechzylinder 12, 13 und die Außenhülle 16 werden so angeordnet, daß ein Labyrinthkanalsystem gemäß Figur 1 gebildet wird, doch können auch andere Arten von Kanalanordnungen vorkommen. Die Ringe oder Spiralen werden induktiv erhitzt und erhitzen dabei die in Richtung der Pfeile 11 in Fig. 2 strömende Luft. Auch die Außenhülle 16 kann mit Flanschen oder anderen flächenvergrößernden Elementen versehen werden. Die Außenhülle 16 wird zweckmäßig aus keramischem Material hergestellt.Air preheaters for scrap heating and / or for phase compensation can be mentioned as a preferred field of application for the aforementioned embodiment of the invention. The rings 9, 10 (Figure 2) as well as the plate cylinders 12, 13 and the outer shell 16 are arranged so that a labyrinth channel system according to Figure 1 is formed, but other types of channel arrangements can also occur. The rings or spirals are heated inductively and thereby heat the air flowing in the direction of the arrows 11 in FIG. 2. The outer shell 16 can also be provided with flanges or other area-enlarging elements. The outer shell 16 is advantageously made of ceramic material.

Die Wärmeübertragung auf die Luft ist von dem Produkt der Wärmeübertragungszahl α, der wärmeübertragenden Fläche A und der Temperaturdifferenz Δt abhängig. Die übertragene Wärmemenge ist α. A .dt.The heat transfer to the air depends on the product of the heat transfer coefficient α, the heat transfer surface A and the temperature difference Δt. The amount of heat transferred is α. A. German

Bei der beschriebenen Vorrichtung erhält man einen hohen Wert für α bereits bei recht mäßigen Druckabfällen. Die Wärmeübertragungszahl α kann weiter erhöht werden durch Anordnungen zur Erhöhung der Turbulenz des Mediums, wie beispielsweise durch Änderung bestimmter Abmessungen der Ringe 7. Die Ringe haben eine verhältnismäßig große vom Luftstrom berührte Oberfläche A (siehe Fig. 3). Die wärmeübertragende Berührungsfläche A kann auch dadurch leicht vergrößert werden, daß die Ringe mit Flanschen versehen werden. Ein weiterer großer Vorteil besteht darin, daß die Temperaturdifferenz Δt, die durch die höchst zulässige Materialtemperatur und die durch die Aufheizung ansteigende Lufttemperatur begrenzt ist, für jeden Ring individuell beeinflußt werden kann. Dies geschieht, wie bereits erwähnt, beispielsweise dadurch, daß die in den einzelnen Ringen enthaltene Materialmenge unterschiedlich bemessen ist. Damit verändert sich die in dem betreffenden Ring in Wärme umgesetzte elektrische Leistung. Für jeden Ring kann daher ein maximaler Wert für At und damit eine maximale Wärmeübertragung erreicht werden.In the device described, a high value for α is obtained even with fairly moderate pressure drops. The heat transfer coefficient α can be increased further by arrangements for increasing the turbulence of the medium, such as, for example, by changing certain dimensions of the rings 7. The rings have a relatively large surface A which is in contact with the air flow (see FIG. 3). The heat-transferring contact area A can also be slightly increased by providing the rings with flanges. Another great advantage is that the temperature difference Δt, which is limited by the maximum permissible material temperature and the air temperature rising due to the heating, can be individually influenced for each ring. As already mentioned, this takes place, for example, in that the amount of material contained in the individual rings is dimensioned differently. This changes the electrical power converted into heat in the ring in question. A maximum value for At and therefore a maximum heat transfer can therefore be achieved for each ring.

Figur 3 zeigt detaillierter den Weg der durch die Vorrichtung strömenden Luft (siehe die Pfeile 11) sowie die Anordnung der strömungstrennenden Blechzylinder 12, 13, die mit den Ringen 7 zusammen induktiv erwärmt werden können. Durch unterschiedliche Plazierung der Ringe (siehe beispielsweise rechts in Fig. 3 die Bezugszeichen 8 und 14) und durch verschiedene Materialmengen in den einzelnen Ringen (siehe rechts in Figur 3 die unterschiedlich dickwandigen Rohre 15 und 16) kann eine optimale Wärmeübertragung erzielt werden. Die Turbulenz kann auch durch Verschiebung einzelner Ringe, beispielsweise jedes zehnten Ringes (siehe den Ring 17 in Fig. 3) erhöht werden. Es können auch andere nicht dargestellte, die Turbulenz erhöhende Einsätze vorgesehen werden.FIG. 3 shows in more detail the path of the air flowing through the device (see arrows 11) and the arrangement of the flow-separating sheet metal cylinders 12, 13 which can be inductively heated together with the rings 7. By placing the rings differently (see, for example, the reference numerals 8 and 14 on the right in FIG. 3) and by different amounts of material in the individual rings (see the pipes 15 and 16 of different thicknesses on the right in FIG. 3), optimal heat transfer can be achieved. The turbulence can also be caused by shifting individual rings, for example every tenth Ring (see the ring 17 in Fig. 3) can be increased. Other inserts, not shown, which increase the turbulence can also be provided.

Mit zentralen Rohren sind solche gemeint, die innerhalb der einzelnen Induktionsspulen verlaufen. Es versteht sich, daß diese nicht genau konzentrisch im Verhältnis zur Spule verlaufen müssen. Eine gewisse Seitenverschiebung ist unschädlich, und es kann von ihr Gebrauch gemacht werden, um eine geeignete Plazierung der Ringe, Spiralen usw. zu ermöglichen.Central tubes are those that run within the individual induction coils. It goes without saying that these do not have to run exactly concentrically in relation to the coil. Some side shift is harmless and can be used to allow proper placement of the rings, spirals, etc.

Die verschiedenen Turbulenz erzeugenden Elemente können separat, also getrennt von den Ringen oder Spiralen,oder an den Ringen oder Spiralen angeordnet sein. Eine Veränderung der Lage der verschiedenen Ringe kann über die ganze Länge der Heizvorrichtung oder über gewisse Teile derselben vorgesehen werden.The various turbulence-generating elements can be arranged separately, that is to say separately from the rings or spirals, or on the rings or spirals. A change in the position of the different rings can be provided over the entire length of the heating device or over certain parts thereof.

Die Erfindung kann im Rahmen des offenbarten allgemeinen Erfindungsgedankens in vielfacher Weise variiert werden.The invention can be varied in many ways within the scope of the general inventive idea disclosed.

Claims (8)

1. Vorrichtung zur Erwärmung eines flüssigen oder gasförmigen Mediums, wie Luft, Wasser usw., bei der um eine oder mehrere zentrale Leitungen (1) für das zu erwärmende Medium eine oder mehrere elektrische Induktionsspulen (2) angeordnet sind, wobei innerhalb der Leitungen (1) Ringe (7) oder Spiralen aus Metall angeordnet sind, die einen oder mehrere elektrisch geschlossene Kreise bilden, die bei Speisung der Spulen induktiv erhitzt werden, dadurch gekennzeichnet, daß ein Kanalsystem für das Medium in Labyrinthform vorhanden ist mit einem äußeren Kanal (3),einem .oder mehreren zu diesem konzentrischen, inneren Kanal (4) und einem Innenrohr (5), welche das Medium der Reihe nach passiert, und daß in mindestens einem dieser Kanäle oder dem Innenrohr metallische Ringe (7) oder Spiralen angeordnet sind, die entweder unmittelbar oder mit Hilfe kurzschließender Elemente elektrische Kurzschlußkreise bilden, wobei sich die in diesen Kurzschlußkreisen liegenden Teile bei Speisung der Spulen (2) induktiv erhitzen.1. Device for heating a liquid or gaseous medium, such as air, water, etc., in which one or more electrical induction coils (2) are arranged around one or more central lines (1) for the medium to be heated, wherein within the lines ( 1) Rings (7) or spirals made of metal are arranged, which form one or more electrically closed circles which are heated inductively when the coils are supplied, characterized in that a channel system for the medium is present in the form of a labyrinth with an outer channel (3 ), one or more concentric to this inner channel (4) and an inner tube (5), which passes through the medium in sequence, and that in at least one of these channels or the inner tube, metallic rings (7) or spirals are arranged, which form electrical short-circuit circuits either directly or with the aid of short-circuiting elements, the parts lying in these short-circuit circuits being supplied with the coils (2) i heat inductively. 2. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß die Kanäle (3, 4) gegeneinander radial durch Zylinder (6) aus Blech oder aus einem anderen metallischen Material getrennt sind, welches bei der Speisung der Spulen gleichzeitig mit den Ringen (7) oder den Spiralen erhitzt wird.2. Device according to claim 1, characterized in that the channels (3, 4) are separated radially from one another by cylinders (6) made of sheet metal or of another metallic material which, when feeding the coils, simultaneously with the rings (7) or the spirals is heated. 3. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Ringe (7) in zwei oder mehreren konzentrischen Schichten, zweckmäßigerweise in einer oder mehreren Schichten in jedem Kanal (3, 4) angeordnet sind.3. Device according to one of the preceding claims, characterized in that the rings (7) in two or more concentric layers, advantageously in one or more layers in each channel (3, 4) are arranged. 4. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß aus Ringen (7) oder Spiralen bestehende kurzgeschlossene metallische Kreise axial hintereinander angeordnet sind.4. Device according to one of the preceding claims, characterized in that short-circuited metallic circles consisting of rings (7) or spirals are arranged axially one behind the other. 5. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß zwischen den äußersten Ringen und/oder Spiralen und den Spulen eine Trennwand (16) aus nicht elektrisch leitendem Material, wie z.B. aus keramischem Material, Kunststoff, Glas usw. und/ oder aus Blechmaterial, angeordnet ist, welche Wand zweckmäßig für das Medium undurchlässig ist.5. Device according to one of the preceding claims, characterized in that between the outermost rings and / or spirals and the coils a partition (16) made of non-electrically conductive material, such as. made of ceramic material, plastic, glass, etc. and / or sheet metal material, which wall is expediently impermeable to the medium. 6. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Ringe (7), die Spiralen und/oder die Kanäle (3, 4) mit Elementen versehen sind, die in dem hindurchströmenden Medium (17) Turbulenzen verursachen.6. Device according to one of the preceding claims, characterized in that the rings (7), the spirals and / or the channels (3, 4) are provided with elements which cause turbulence in the medium flowing through (17). 7. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Zylinder (6) und/oder die Ringe (7) und/oder die äußere Trennwand (16) mit flächenvergrößernden Teilen versehen sind.7. Device according to one of the preceding claims, characterized in that the cylinders (6) and / or the rings (7) and / or the outer partition (16) are provided with area-enlarging parts. 8-. Vorrichtung nach einem der vorhergehenden Ansprüche,. dadurch gekennzeichnet, daß die Ringe zur Optimierung der Erhitzung mit unterschiedlichen Materialmengen ausgeführt sind. / 8th-. Device according to one of the preceding claims. characterized in that the rings are designed to optimize the heating with different amounts of material. /
EP82108626A 1981-09-24 1982-09-18 Apparatus for heating a liquid or gaseous medium Withdrawn EP0075811A1 (en)

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SE8105640 1981-09-24
SE8105640A SE442696B (en) 1981-09-24 1981-09-24 DEVICE FOR HEATING OF GAS OR LIQUID MEDIA

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WO1989012204A1 (en) * 1988-06-07 1989-12-14 Eastern Electricity Board Induction heater
FR2654888A1 (en) * 1989-11-17 1991-05-24 Lane Patrick Hot gas, vapour and fluid generator with thermo-induction
EP0462544A1 (en) * 1990-06-18 1991-12-27 Hidec Corporation Ltd. Electromagnetic induction heater
EP0627678A1 (en) * 1993-04-09 1994-12-07 Félix Seye Heating device for water -or other heat transfer fluid- radiator
EP0849978A2 (en) * 1996-12-20 1998-06-24 Rayotherm Espana Vergely, S.L. Device for warming heating liquids at low pressure or with closed expansion vessel
US6118111A (en) * 1996-03-15 2000-09-12 Bbmr Limited Fluid heater
US7731689B2 (en) 2007-02-15 2010-06-08 Baxter International Inc. Dialysis system having inductive heating
EP2213140B1 (en) * 2007-10-18 2013-03-06 Koninklijke Philips Electronics N.V. Flow-through induction heater
EP2689946A1 (en) * 2012-07-24 2014-01-29 Behr GmbH & Co. KG Heating device
US8803044B2 (en) 2003-11-05 2014-08-12 Baxter International Inc. Dialysis fluid heating systems
EP2194331A3 (en) * 2008-12-02 2015-03-25 BSH Hausgeräte GmbH Domestic continuous-flow heater
CN104534673A (en) * 2014-12-16 2015-04-22 爱科奔（大连）电器有限公司 Induced current fluid induction heating device and water supply system with same
EP3166369A3 (en) * 2015-11-09 2017-08-16 Pace, Inc. Inductive heater for area array rework system and soldering handpieces
WO2018147758A1 (en) * 2017-02-13 2018-08-16 Лев Захарович ДУДАРЕВ Induction fluid heater
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WO1989012204A1 (en) * 1988-06-07 1989-12-14 Eastern Electricity Board Induction heater
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EP0462544A1 (en) * 1990-06-18 1991-12-27 Hidec Corporation Ltd. Electromagnetic induction heater
US5237144A (en) * 1990-06-18 1993-08-17 Nikko Co., Ltd. Electromagnetic induction heater
EP0627678A1 (en) * 1993-04-09 1994-12-07 Félix Seye Heating device for water -or other heat transfer fluid- radiator
US6118111A (en) * 1996-03-15 2000-09-12 Bbmr Limited Fluid heater
EP0849978A2 (en) * 1996-12-20 1998-06-24 Rayotherm Espana Vergely, S.L. Device for warming heating liquids at low pressure or with closed expansion vessel
EP0849978A3 (en) * 1996-12-20 1998-09-02 Rayotherm Espana Vergely, S.L. Device for warming heating liquids at low pressure or with closed expansion vessel
US8803044B2 (en) 2003-11-05 2014-08-12 Baxter International Inc. Dialysis fluid heating systems
US7731689B2 (en) 2007-02-15 2010-06-08 Baxter International Inc. Dialysis system having inductive heating
EP2213140B1 (en) * 2007-10-18 2013-03-06 Koninklijke Philips Electronics N.V. Flow-through induction heater
EP2194331A3 (en) * 2008-12-02 2015-03-25 BSH Hausgeräte GmbH Domestic continuous-flow heater
EP2689946A1 (en) * 2012-07-24 2014-01-29 Behr GmbH & Co. KG Heating device
US9848464B2 (en) 2012-07-24 2017-12-19 Mahle International Gmbh Heating device
CN104534673A (en) * 2014-12-16 2015-04-22 爱科奔（大连）电器有限公司 Induced current fluid induction heating device and water supply system with same
EP3166369A3 (en) * 2015-11-09 2017-08-16 Pace, Inc. Inductive heater for area array rework system and soldering handpieces
EP3361828A1 (en) * 2015-11-09 2018-08-15 Pace, Inc. Convective soldering and rework apparatus
US10237926B2 (en) 2015-11-09 2019-03-19 Pace, Inc. Inductive heater for area array rework system and soldering handpieces
WO2018147758A1 (en) * 2017-02-13 2018-08-16 Лев Захарович ДУДАРЕВ Induction fluid heater
DE102021203910A1 (en) 2021-04-20 2022-04-21 Vitesco Technologies GmbH Induction heating device and electric heater for a vehicle

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US4471191A (en) 1984-09-11
ES515835A0 (en) 1983-06-01
CA1185663A (en) 1985-04-16
SE8105640L (en) 1983-03-25
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BR8205581A (en) 1983-08-30
SE442696B (en) 1986-01-20
JPS5866283A (en) 1983-04-20

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