EP0075811A1 - Appareil pour échauffer un milieu liquide ou gazeux - Google Patents

Appareil pour échauffer un milieu liquide ou gazeux 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
Authority
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.)
Withdrawn
Application number
EP82108626A
Other languages
German (de)
English (en)
Inventor
Ingemar Ing. Greis
Artur Ing. Östlund
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ABB Norden Holding AB
Original Assignee
ASEA AB
Stal Laval Apparat AB
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by ASEA AB, Stal Laval Apparat AB filed Critical ASEA AB
Publication of EP0075811A1 publication Critical patent/EP0075811A1/fr
Withdrawn legal-status Critical Current

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    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00Heating by electric, magnetic or electromagnetic fields
    • H05B6/02Induction heating
    • H05B6/10Induction heating apparatus, other than furnaces, for specific applications
    • H05B6/105Induction heating apparatus, other than furnaces, for specific applications using a susceptor
    • H05B6/108Induction heating apparatus, other than furnaces, for specific applications using a susceptor for heating a fluid
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H1/00Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
    • F24H1/10Continuous-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
    • F24H1/101Continuous-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.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Electromagnetism (AREA)
  • General Induction Heating (AREA)
EP82108626A 1981-09-24 1982-09-18 Appareil pour échauffer un milieu liquide ou gazeux Withdrawn EP0075811A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8105640A SE442696B (sv) 1981-09-24 1981-09-24 Anordning for vermning av gas- eller vetskeformiga media
SE8105640 1981-09-24

Publications (1)

Publication Number Publication Date
EP0075811A1 true EP0075811A1 (fr) 1983-04-06

Family

ID=20344620

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82108626A Withdrawn EP0075811A1 (fr) 1981-09-24 1982-09-18 Appareil pour échauffer un milieu liquide ou gazeux

Country Status (7)

Country Link
US (1) US4471191A (fr)
EP (1) EP0075811A1 (fr)
JP (1) JPS5866283A (fr)
BR (1) BR8205581A (fr)
CA (1) CA1185663A (fr)
ES (1) ES8306951A1 (fr)
SE (1) SE442696B (fr)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2627048A1 (fr) * 1988-02-10 1989-08-11 Electricite De France Cuve pour le chauffage d'un liquide par induction
WO1989012204A1 (fr) * 1988-06-07 1989-12-14 Eastern Electricity Board Four a induction
FR2654888A1 (fr) * 1989-11-17 1991-05-24 Lane Patrick Generateur de vapeur, de fluide et de gaz chaud a thermo-induction.
EP0462544A1 (fr) * 1990-06-18 1991-12-27 Hidec Corporation Ltd. Appareil de chauffage à induction électromagnétique
EP0627678A1 (fr) * 1993-04-09 1994-12-07 Félix Seye Dispositif de chauffage pour radiateur à eau ou autre liquide caloporteur
EP0849978A2 (fr) * 1996-12-20 1998-06-24 Rayotherm Espana Vergely, S.L. Dispositif pour chauffager les liquides de chauffage à basse pression ou avec un vase d'expansion fermé
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 (fr) * 2007-10-18 2013-03-06 Koninklijke Philips Electronics N.V. Dispositif de chauffage par induction à écoulement traversant
EP2689946A1 (fr) * 2012-07-24 2014-01-29 Behr GmbH & Co. KG Dispositif de chauffage
US8803044B2 (en) 2003-11-05 2014-08-12 Baxter International Inc. Dialysis fluid heating systems
EP2194331A3 (fr) * 2008-12-02 2015-03-25 BSH Hausgeräte GmbH Chauffe-eau instantané
CN104534673A (zh) * 2014-12-16 2015-04-22 爱科奔(大连)电器有限公司 诱导电流流体感应加热装置及应用该装置的供水系统
EP3166369A3 (fr) * 2015-11-09 2017-08-16 Pace, Inc. Appareil de chauffage à induction pour système de reprise matriciel et de soudage de pièces à main
WO2018147758A1 (fr) * 2017-02-13 2018-08-16 Лев Захарович ДУДАРЕВ Unité de chauffage par induction de liquides
DE102021203910A1 (de) 2021-04-20 2022-04-21 Vitesco Technologies GmbH Induktionsheizvorrichtung sowie elektrische Heizung für ein Fahrzeug

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4869734A (en) * 1986-03-03 1989-09-26 Tri-Dim Filter Corporation Air cleaning system
DE3781154T2 (de) * 1987-02-27 1993-04-22 Tri Dim Filter Corp Heizvorrichtung fuer kohlepartikeln.
NZ233841A (en) * 1990-05-29 1993-01-27 Transflux Holdings Ltd Continuous flow transformer water heater
EP0884928B1 (fr) * 1997-06-11 2007-03-28 Matsushita Electric Industrial Co., Ltd. Dispositif de chauffage des fluides par induction
US6147336A (en) * 1998-02-26 2000-11-14 Japanese Research And Development Association For Application Of Electronic Technology In Food Industry Induction heaters for heating food, fluids or the like
US7339144B2 (en) * 2001-07-24 2008-03-04 Magtec Llc Magnetic heat generation
US7573009B2 (en) * 2001-07-24 2009-08-11 Magtec Energy, Llc Controlled magnetic heat generation
US7420144B2 (en) * 2002-07-23 2008-09-02 Magtec Llc Controlled torque magnetic heat generation
US20050115243A1 (en) * 2003-12-01 2005-06-02 Adle Donald L. Flywheel vane combustion engine
US20050169814A1 (en) * 2004-01-30 2005-08-04 Joshua Rosenthal Portable vaporizer
CN100398900C (zh) * 2005-04-30 2008-07-02 中国科学院等离子体物理研究所 基于多层管道结构获得高温热流体的方法
US20090092384A1 (en) * 2007-08-09 2009-04-09 Shimin Luo High frequency induction heating instantaneous tankless water heaters
JP5315000B2 (ja) * 2008-10-23 2013-10-16 ホシザキ電機株式会社 蒸気発生装置
JP2011238449A (ja) * 2010-05-10 2011-11-24 Kame Takeharu 電磁誘導加熱装置及びそれを用いた暖房・給湯装置
DE102012206991A1 (de) * 2012-04-26 2013-10-31 Behr-Hella Thermocontrol Gmbh Heizkörper
DE102013211579A1 (de) * 2013-06-19 2014-12-24 Behr Gmbh & Co. Kg Wärmetauschereinrichtung und Heizvorrichtung
US10451139B2 (en) * 2017-11-30 2019-10-22 Honeywell International Inc. Damping coefficient-regulating inductive heating systems and isolator assemblies including the same
CN108800546B (zh) * 2018-07-01 2020-12-29 山东世普润能源科技有限公司 压力式大功率双侧电磁致热器
GB2577929A (en) * 2018-10-11 2020-04-15 Pre Tech Limited Point-of-use induction water heater
CN109855285A (zh) * 2019-03-04 2019-06-07 田佳龙 一种新能源永磁磁化热水机
RU2755521C2 (ru) * 2019-05-13 2021-09-16 Общество с ограниченной ответственностью "Инжиниринговая Компания "Пульсар Ойл" Способ нагрева жидких сред

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD11261A (fr) *
US1260564A (en) * 1917-09-26 1918-03-26 Carl Edward Magnusson Electric heater.
DE841178C (de) * 1951-05-13 1952-06-13 Otto Junker Fa Elektrisch induktiv beheizter Durchlauferhitzer
GB787125A (en) * 1952-12-23 1957-12-04 Carl Schorg Improvements in or relating to apparatus for heating liquids, gases or liquid or gaseous suspensions by electrical induction

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1818953A (en) * 1929-02-18 1931-08-11 W R Everett Electric heater
US1981632A (en) * 1932-04-30 1934-11-20 Ajax Electrothermic Corp Heating apparatus
US2171080A (en) * 1938-05-04 1939-08-29 George B Ely Induction heat transformer
US2407562A (en) * 1942-08-17 1946-09-10 Einar G Lofgren Induction heater
US2644881A (en) * 1948-12-20 1953-07-07 Schorg Carl Christian Inductively heated electrical contact furnace with preheater
DE972114C (de) * 1951-02-11 1959-05-21 Carl Dipl-Ing Schoerg Anordnung zur induktiven Erhitzung stroemender Medien
US3696223A (en) * 1970-10-05 1972-10-03 Cragmet Corp Susceptor
US3821508A (en) * 1973-04-23 1974-06-28 Hagerty Res Dev Co Inc Method and apparatus for heating fluid
DE2745135A1 (de) * 1977-10-07 1979-04-12 Kali Chemie Ag Induktionswaermetauscher

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD11261A (fr) *
US1260564A (en) * 1917-09-26 1918-03-26 Carl Edward Magnusson Electric heater.
DE841178C (de) * 1951-05-13 1952-06-13 Otto Junker Fa Elektrisch induktiv beheizter Durchlauferhitzer
GB787125A (en) * 1952-12-23 1957-12-04 Carl Schorg Improvements in or relating to apparatus for heating liquids, gases or liquid or gaseous suspensions by electrical induction

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2627048A1 (fr) * 1988-02-10 1989-08-11 Electricite De France Cuve pour le chauffage d'un liquide par induction
WO1989012204A1 (fr) * 1988-06-07 1989-12-14 Eastern Electricity Board Four a induction
FR2654888A1 (fr) * 1989-11-17 1991-05-24 Lane Patrick Generateur de vapeur, de fluide et de gaz chaud a thermo-induction.
EP0462544A1 (fr) * 1990-06-18 1991-12-27 Hidec Corporation Ltd. Appareil de chauffage à induction électromagnétique
US5237144A (en) * 1990-06-18 1993-08-17 Nikko Co., Ltd. Electromagnetic induction heater
EP0627678A1 (fr) * 1993-04-09 1994-12-07 Félix Seye Dispositif de chauffage pour radiateur à eau ou autre liquide caloporteur
US6118111A (en) * 1996-03-15 2000-09-12 Bbmr Limited Fluid heater
EP0849978A2 (fr) * 1996-12-20 1998-06-24 Rayotherm Espana Vergely, S.L. Dispositif pour chauffager les liquides de chauffage à basse pression ou avec un vase d'expansion fermé
EP0849978A3 (fr) * 1996-12-20 1998-09-02 Rayotherm Espana Vergely, S.L. Dispositif pour chauffager les liquides de chauffage à basse pression ou avec un vase d'expansion fermé
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 (fr) * 2007-10-18 2013-03-06 Koninklijke Philips Electronics N.V. Dispositif de chauffage par induction à écoulement traversant
EP2194331A3 (fr) * 2008-12-02 2015-03-25 BSH Hausgeräte GmbH Chauffe-eau instantané
EP2689946A1 (fr) * 2012-07-24 2014-01-29 Behr GmbH & Co. KG Dispositif de chauffage
US9848464B2 (en) 2012-07-24 2017-12-19 Mahle International Gmbh Heating device
CN104534673A (zh) * 2014-12-16 2015-04-22 爱科奔(大连)电器有限公司 诱导电流流体感应加热装置及应用该装置的供水系统
EP3166369A3 (fr) * 2015-11-09 2017-08-16 Pace, Inc. Appareil de chauffage à induction pour système de reprise matriciel et de soudage de pièces à main
EP3361828A1 (fr) * 2015-11-09 2018-08-15 Pace, Inc. Appareil de réusinage et de brasage par convection
US10237926B2 (en) 2015-11-09 2019-03-19 Pace, Inc. Inductive heater for area array rework system and soldering handpieces
WO2018147758A1 (fr) * 2017-02-13 2018-08-16 Лев Захарович ДУДАРЕВ Unité de chauffage par induction de liquides
DE102021203910A1 (de) 2021-04-20 2022-04-21 Vitesco Technologies GmbH Induktionsheizvorrichtung sowie elektrische Heizung für ein Fahrzeug

Also Published As

Publication number Publication date
ES515835A0 (es) 1983-06-01
CA1185663A (fr) 1985-04-16
BR8205581A (pt) 1983-08-30
SE8105640L (sv) 1983-03-25
US4471191A (en) 1984-09-11
JPS5866283A (ja) 1983-04-20
ES8306951A1 (es) 1983-06-01
SE442696B (sv) 1986-01-20

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PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

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Inventor name: GREIS, INGEMAR, ING.

Inventor name: OESTLUND, ARTUR, ING.