DE102017100564A1 - Fluid heating device and method for heating a fluidic heat transfer medium - Google Patents

Abstract

The invention relates to a fluid heating device, comprising a fluid channel for passing a fluidic heat transfer medium, arranged in or on the fluid channel or formed by this heat transfer body can be traversed by the heat transfer medium passages and an electromagnetic excitation device which is inductively coupled to the heat transfer body. Moreover, the invention also relates to a method for heating a fluidic heat transfer medium and a device having at least one fluid heating device.

Description

The invention relates to a fluid heating device, comprising a fluid channel for passing a fluidic heat transfer medium.

Moreover, the invention relates to a method for heating a fluidic heat transfer medium with a fluid heating device.

A fluid heating device for heating a fluidic heat transfer medium experiences a variety of uses. The heat transfer medium can be a liquid or a gas, which in the present case can also be understood to mean a gas mixture. Liquid heat transfer media (in particular water) are used, for example, in fluid heaters in the form of instantaneous water heaters. Exemplary fields of application are in the sanitary sector, in drinks dispensers or auxiliary heaters for motor vehicles. Fluid heaters with a gaseous heat transfer medium (in particular air) are used, for example, in drying devices, in electrically operated fan heaters and in wind tunnels.

In conventional fluid heating, the heating of the heat transfer medium via an ohmic heating element, which is heated by exposure to electrical energy and dissipates the heat to the passing heat transfer medium occurs. Such fluid heaters require comparatively large space. The response time is not inconsiderable, whereby the efficiency of conventional fluid heaters is rather low. This limits scaling options in terms of size and / or performance.

The object of the present invention is to provide a fluid heating device and a method for heating a fluidic heat transfer medium with which a structurally simple heating of the heat transfer medium is possible with regard to the possibility of scaling, wherein advantageously a high level of operational reliability can be ensured.

This object is achieved by a fluid heating device according to the invention, comprising a fluid channel for passing a fluid heat transfer medium, arranged in or on the fluid channel or formed by this heat transfer body can be traversed by the heat transfer medium passages and an electromagnetic excitation device which is inductively coupled to the heat transfer body.

In the fluid heating apparatus according to the present invention, energy provided by the electromagnetic excitation means can be inductively transferred to the heat transfer body with high efficiency. By the inductive excitation of the heat transfer body, a physical connection between the excitation means and the heat transfer body can be saved. This allows a structurally simple embodiment of the fluid heater and allows to keep its production costs low. Induction forms in the heat transfer body eddy currents, causing it to be heated. Heat can be delivered to the heat transfer medium flowing through the passages of the heat transfer body. It is particularly advantageous if the heat transfer body has a porous or foam-like nature and the contact surface of the heat transfer medium inner surface in relation to the outer surface or the volume of the heat transfer body is large to very large. The mass of the heat transfer body to be heated can be kept low, whereby a fast response time of the fluid heater is ensured. In contrast to a conventional fluid heating device in the sense of a water heater, in which the transfer of heat is inert and inefficient in the manner of a heat exchanger, the fluid heater according to the invention in contrast can be regarded as a kind of "energy exchanger". The electrical energy acting on the excitation device leads through the inductive coupling to the heating of the heat transfer body and can be implemented by this with high volumetric power for heating the heat transfer medium, wherein its contact with the exciter device itself is not required.

The excitation device advantageously has at least one coil. It is preferably provided that the coil extends in a flow direction of the heat transfer medium through the fluid channel over the entire length of the heat transfer body.

In an advantageous embodiment, a coil surrounding a wall of the fluid channel is advantageously provided as a coil. Windings of the cylindrical coil surround the fluid channel. An alternating magnetic field produced by the action of the alternating current coil can be inductively coupled into the heat transfer body arranged inside the coil. The alternating field induces eddy currents in the heat transfer body. Windings of the coil can bear directly or indirectly, for example via an insulating medium, on the wall of the fluid channel. When using a cylindrical coil, the fluid channel may have, for example, a round and in particular circular cross-section transverse to the flow direction of the heat transfer medium.

Alternatively or additionally, it can be provided in an advantageous implementation, that is provided as a coil laterally adjacent to a wall of the fluid channel coil, which may in particular be a flat coil, for example, when designing the fluid channel as a flat channel. The arrangement of the coil laterally adjacent to the fluid channel allows for easy scaling and assembly of the fluid heater. For example, an alternating magnetic field generated by the AC-energized coil is oriented transversely to a flow direction of the heat transfer medium through the fluid passage.

It is advantageous if the heat transfer body, at least partially, is made of a porous or foam-like material, wherein the passages are formed by the porous or foam-like nature of the heat transfer body. The introduction of separate passages in the heat transfer body is not required. As already mentioned, in the case of a porous design of the heat transfer body, it is possible to provide a large to very large inner surface in relation to the outer surface and to the volume. This allows an efficient heat transfer from the heat transfer body to the heat transfer medium. With low mass to be heated, there is a fast response time of the fluid heater. The same applies to a foam-like design of the heat transfer body.

In another advantageous implementation of the fluid heating device can be provided that the passages are designed as channels, for example as holes in the heat transfer body.

• - einem metallischen Material, das vorliegend insbesondere auch metallische Legierungen umfassen kann. Beispielsweise kommt ein Metallschaum oder ein poröses Sintermetall zum Einsatz;
• - einem keramischen Material, zum Beispiel einem faserkeramischen Material (CMC, Ceramic Matrix Composite), das eine mikroporöse Beschaffenheit zur Ausbildung der Durchgänge aufweist;
• - einem Verbundwerkstoff, insbesondere einem Faserverbundwerkstoff. Beispielsweise wird ein kohlenstofffaserverstärkter Kunststoff (KFK) oder eine Faserkeramik (CMC, Ceramic Matrix Composite) eingesetzt. Zum Beispiel wird ein sogenanntes CC (Carbon-Carbon)-Material für den Wärmeübertragungskörper oder als Ausgangsmaterial für denselben verwendet. Dieses CC-Material kann pyrolisierte Viskosefasern aufweisen, die in Phenolharz eingebettet sind, wobei das Gefüge zum Ausbilden des CC-Materials pyrolisiert ist. Eine weitere Infiltration mit Phenolharz und Aushärtung kann vorgesehen sein;

• - Kohlenstoff oder einem kohlenstoffhaltigen Material, beispielsweise Graphit, Kohlefilz, Kohleschaum, Aktivkohle; auch kohlenstoffhaltige Verbindungen sind denkbar, insbesondere Siliciumcarbid;
• - aus einem Sintermaterial, etwa einem Sintermetall.

It proves to be favorable if the heat transfer body comprises, wholly or partly, at least one of the materials mentioned below or consists of or is made of at least one of the following materials, of course, combinations are also possible:

• - A metallic material, which in the present case may include in particular metallic alloys. For example, a metal foam or a porous sintered metal is used;
• a ceramic material, for example a ceramic-ceramic material (CMC), which has a microporous nature to form the passages;
• - A composite material, in particular a fiber composite material. For example, a carbon fiber reinforced plastic (KFK) or a ceramic ceramic (CMC, Ceramic Matrix Composite) is used. For example, a so-called CC (carbon-carbon) material is used for the heat transfer body or as a raw material for the same. This CC material may comprise pyrolyzed viscose fibers embedded in phenolic resin, the structure for pyrolyzing the CC material being pyrolyzed. Further infiltration with phenolic resin and curing may be provided;

• Carbon or a carbonaceous material, for example graphite, carbon felt, carbon foam, activated carbon; also carbon-containing compounds are conceivable, in particular silicon carbide;
• - From a sintered material, such as a sintered metal.

The heat transfer body may be made of or include an electrically conductive material. It may be provided that the heat transfer body is only electrically conductive in an operating state and for this purpose is initially to bring to operating temperature (for example, when manufactured from ZrO ₂ ). This could be done with a separate heating element and / or by means of the heat transfer medium.

As already mentioned, it may be provided that the fluid channel is designed to be round in cross-section or that the fluid channel is designed as a flat channel.

In an advantageous implementation of the fluid heating, it is advantageous if the heat transfer body is arranged in the fluid channel, in particular transversely to a flow direction of the heat transfer medium is positively received in the fluid channel. This makes it possible to flow through the transmission body over the entire cross section of the fluid channel with the heat transfer medium. The heat transfer body can effectively form a "core" of the aforementioned coil.

In one embodiment it can be provided that the passages of the heat transfer body are aligned along a flow direction of the heat transfer medium through the heat transfer body.

In an advantageous implementation can be provided that the heat transfer body is designed sleeve-shaped and a space between a wall of the fluid channel and the heat transfer body is provided, that preferably the passages are aligned transversely or perpendicular to the flow direction of the heat transfer medium and the heat transfer body is upstream of passages, the Heat transfer body can be acted upon via the intermediate space with the heat transfer medium. On the upstream side, the heat transfer body has no passages. The inflowing heat transfer medium can enter the intermediate space and from there flow transversely and in particular perpendicular to the extension of the fluid channel through the heat transfer body.

In an advantageous embodiment of the fluid heating device according to the invention can be provided that the exciter device, at least in sections, is arranged in the fluid channel. For example, the exciter device has at least one coil arranged in the fluid channel, which may be, for example, a cylindrical coil. The solenoid can be aligned coaxially with the fluid channel.

In at least partially arranged in the fluid passage excitation means is advantageously provided that the heat transfer body is designed sleeve-shaped and an intermediate space between a wall of the fluid channel and the heat transfer body is provided, wherein the heat transfer body surrounds the exciter at least in sections. In particular, the heat transfer body can surround a cylindrical coil of the exciter device, coaxial with which the heat transfer body can be aligned. Passages may be formed transversely or perpendicular to the flow direction of the heat transfer medium in the heat transfer body, and on a downstream side, the heat transfer body may be free of passageways. In such an embodiment, the coil could be convectively cooled with the inflowing heat transfer medium. The heat transfer medium can flow from the inside to the outside through the heat transfer body, enter the space between the heat transfer body and the wall and laterally flow past the heat transfer body. Such a fluid heating device has a very compact design.

In particular, it can be provided that the heat transfer body is aligned coaxially to the fluid channel.

In an advantageous embodiment of the fluid heating device is advantageously provided that the heat transfer body forms a wall of the fluid channel.

In another advantageous embodiment of the fluid heating device can be provided that the heat transfer body forms a receiving space and arranged in this flowable heat transfer elements, which are inductively coupled to the exciter device and between which the passages forming gaps are present. The heat transfer elements are accommodated in the receiving space. The heat transfer medium may flow past the heat transfer elements by the gaps between them. For efficient heat transfer, it makes sense if the heat transfer elements have a small size, for example, a diameter of 1 mm or preferably less, about 0.1 mm. In turn, in a preferred embodiment, the heat transfer elements may comprise passages formed, for example, by a porous or foamy nature of the heat transfer elements. This gives the possibility of enlarging the surface of the heat transfer body which can be contacted by the heat transfer medium.

It is advantageous if the heat transfer elements are received touching each other in the receiving space. This is for example advantageous, it will be discussed below, if the heat transfer elements are electrically conductive and can be used as ohmic heating elements for heating the heat transfer medium.

The heat transfer elements can be designed spherical, for example with a diameter of 1 mm or less.

For effective coupling of inductive energy in the heat transfer body, it is advantageous if the heat transfer body or the heat transfer elements is ferromagnetic or ferrimagnetic / are.

Also, a paramagnetic design of the heat transfer body or the heat transfer elements is conceivable.

It is advantageous if the heat transfer body or the heat transfer elements made of an electrically conductive material and coupled to a power supply device or can be coupled for passing an electric current through the heat transfer body or the heat transfer elements. This gives the possibility of applying electrical energy to the heat transfer body or elements via the inductive coupling (via DC or AC). The heat transfer body thereby forms an ohmic heating element for additional energy transfer to the heat transfer medium.

The heat transfer body or the heat transfer elements (their combined specific surface area in relation to the volume of the heat transfer body) advantageously have a specific surface area of at least 1,000 m ² / m ³ , preferably at least 100,000 m ² / m ³ , more preferably at least 1,000,000 m ² / m ³ . For example, with spherical heat transfer elements in dense bed with a ball diameter of 1 mm, a volume-specific surface area of approximately 1,000 to 5,000 m ² / m ³ can be achieved. For a compact ball bed with a diameter of 0.1 mm, the volume-specific surface is already approximately 10,000 to 50,000 m ² / m ³ . The above-mentioned porous nature CC material may have a volume specific surface area of about 1,000,000 to 5,000,000 m ² / m ³ . Even higher values are achieved with activated carbon with approximately 100,000,000 m ² / m ³ and more.

Advantageously, an electrical insulation medium is provided between the excitation means and the heat transfer body to increase the reliability of the fluid heating apparatus, for example for sanitary applications. The electrical insulation medium may preferably have a lower magnetic susceptibility than the heat transfer body, so that the alternating magnetic field of the exciter essentially acts only on the heat transfer body, but not the insulation medium. The material used for the insulating medium is, for example, plastic (for example for low-temperature applications) or an aluminum oxide fiber ceramic (eg Whipox), the latter also being used for thermal insulation.

Alternatively or additionally, it is favorable if a thermal insulation medium is provided between the exciter device and the heat transfer body in order to avoid unwanted waste heat of the heat transfer body.

Preferably, the electrical and thermal isolation media are identical, i. H. An insulation medium may be provided which thermally and electrically isolates the exciter device from the heat transfer body.

The present invention also relates to a device having at least one consumer, which has at least one fluid heating device of the aforementioned type, wherein the at least one consumer can be supplied with the heat transfer medium heated by the at least one fluid heating device.

The advantages that can be achieved using the fluid heating device according to the invention can also be achieved in the device according to the invention. For advantageous embodiments of the device, reference is made to advantageous embodiments of the fluid heating device.

The device according to the invention can be designed in different ways and relates to possible uses of the at least one fluid heating device. For example, the device is a sanitary unit or a part thereof, a vending machine or a heating system or a part thereof. The device may be, for example, in gaseous heat transfer medium, an electric fan heater, a drying device, a wind tunnel, a burner or a thermo-electric engine.

Accordingly, the consumer of the device can be designed in different ways. The consumer is, for example, a nozzle, a blower or a pump unit.

The device advantageously comprises a control device and a delivery unit coupled thereto. This makes it possible to control and / or regulate the volume flow of the heat transfer medium, with which the heat transfer body is acted upon. The control device is advantageously coupled to the aforementioned energy supply device in order to control and / or regulate the heating of the heat transfer medium.

The heat transfer medium may, as mentioned, be gaseous. For example, an inert gas (N ₂ , Ar ...) can be used, the device being a burner, for example for cutting operations. The hot gas zone could consist of the defined inert gas. This makes it possible to locally heat or cut even critical materials. As a consumer of the device, a nozzle may be provided which may be configured as an expansion nozzle or coaxial nozzle. In the case of a coaxially configured nozzle, it is possible, as in the case of a conventional cutting torch, to supply a further feed channel for a different fluid or gas (for example oxygen) in order to achieve a specific hot gas effect.

It may be provided in an advantageous embodiment of the fluid heating device according to the invention that this itself comprises a nozzle. It is advantageous if the nozzle, at least in sections, is formed by the heat transfer body. For example, the above-mentioned sleeve-shaped heat transfer body may have a cross-sectional constriction, which is arranged in particular on the output side. The heated after passing through the heat transfer body heat transfer medium can the cross-sectional constriction to achieve a high specific Impulse happen. For example, the nozzle is a Laval nozzle. On the outflow side of the fluid heating device can be provided, for example, in a thermoelectric engine, advantageously an expansion nozzle.

The above-mentioned object is achieved by a method according to the invention for heating a fluid heat transfer medium, in which method the heat transfer medium flows through a heat transfer body arranged in or formed by a fluid channel and is heated by the latter, the heat transfer body being inductively coupled to an exciter device.

The advantages already mentioned in the explanation of the fluid heating device according to the invention can also be achieved when using the method. In this regard, reference may be made to the above statements.

Advantageous embodiments of the method result from advantageous embodiments of the fluid heating device according to the invention. Reference is made to the above statements.

• 1: eine schematische Schnittansicht einer ersten bevorzugten Ausführungsform einer erfindungsgemäßen Fluidheizvorrichtung und einer erfindungsgemäßen Vorrichtung;
• 2: eine schematische Schnittansicht einer zweiten bevorzugten Ausführungsform einer erfindungsgemäßen Fluidheizvorrichtung;
• 3: eine schematische Schnittansicht einer dritten bevorzugten Ausführungsform einer erfindungsgemäßen Fluidheizvorrichtung;
• 4: eine Draufsicht auf die Fluidheizvorrichtung in Richtung des Pfeiles „4“ in 3;
• 5: eine schematische Schnittansicht einer vierten bevorzugten Ausführungsform einer erfindungsgemäßen Fluidheizvorrichtung;
• 6: eine schematische Schnittansicht einer fünften bevorzugten Ausführungsform einer erfindungsgemäßen Fluidheizvorrichtung;
• 7: eine schematische Schnittansicht einer sechsten bevorzugten Ausführungsform einer erfindungsgemäßen Fluidheizvorrichtung und einer erfindungsgemäßen Vorrichtung;
• 8: eine schematische Schnittansicht einer siebten bevorzugten Ausführungsform einer erfindungsgemäßen Fluidheizvorrichtung und einer erfindungsgemäßen Vorrichtung; und
• 9: eine schematische Schnittansicht einer achten bevorzugten Ausführungsform einer erfindungsgemäßen Fluidheizvorrichtung.

The following description of preferred embodiments of the invention is used in conjunction with the drawings for a more detailed explanation of the invention. Embodiments of the fluid heating device according to the invention make it possible to carry out the method according to the invention. Show it:

• 1 a schematic sectional view of a first preferred embodiment of a fluid heating device according to the invention and a device according to the invention;
• 2 a schematic sectional view of a second preferred embodiment of a fluid heating device according to the invention;
• 3 FIG. 2 is a schematic sectional view of a third preferred embodiment of a fluid heating device according to the invention; FIG.
• 4 FIG. 2: a top view of the fluid heating device in the direction of the arrow "4" in FIG 3 ;
• 5 a schematic sectional view of a fourth preferred embodiment of a fluid heating device according to the invention;
• 6 a schematic sectional view of a fifth preferred embodiment of a fluid heating device according to the invention;
• 7 a schematic sectional view of a sixth preferred embodiment of a fluid heating device according to the invention and a device according to the invention;
• 8th FIG. 2 is a schematic sectional view of a seventh preferred embodiment of a fluid heating device according to the invention and a device according to the invention; FIG. and
• 9 FIG. 2: a schematic sectional view of an eighth preferred embodiment of a fluid heating device according to the invention. FIG.

In the following, different advantageous embodiments of a fluid heating device according to the invention will be described, with which advantageous embodiments of the method according to the invention can be carried out in each case. For identical or equivalent features and components of the different embodiments, identical reference numerals are used. Only the essential differences of the fluid heaters will be discussed.

1 shows a schematic sectional view of an occupied by the reference numeral 10 advantageous embodiment of the fluid heater. The fluid heater 10 includes a fluid channel 12 that of a fluidic heat transfer medium 14 in a flow direction can be flowed through by arrows 16 is symbolized. The heat transfer medium 14 may be liquid or gaseous.

The fluid channel 12 indicates in the fluid heater 10 For example, a round and in particular circular cross-section perpendicular to the flow direction 16 on. A wall 18 of the fluid channel 12 summarizes this from the heat transfer medium 14 permeable interior 20 on.

The present is the cross section of the fluid channel 12 not constant. Between a feed section 22 and a delivery section 24 is a broadening section 26 arranged. The cross section of the fluid channel 12 at the feeder section 22 and at the delivery section 24 is identical here. The cross section of the fluid channel 12 at the widening section 26 in the present case is larger than at the feed section 22 and at the delivery section 24 ,

In another embodiment of the invention can be provided that the cross section of the fluid channel 12 constant or substantially constant and no widening section 26 is provided.

The fluid heater 10 includes one in the fluid channel 12 absorbed heat transfer body 28 , The heat transfer body 28 is in the fluid channel 12 in the area of the broadening section 26 arranged. In this case, the heat transfer body 28 so that it fits positively in the fluid channel 12 is included and the wall 18 contacted on the inside.

The heat transfer body 28 In the present case, it is made of a porous material, for example a sintered material, such as a sintered metal. It is also conceivable to use a metal foam. The heat transfer body 28 may alternatively or additionally be made of carbonaceous material or carbon, for example graphite, carbon felt, carbon foam or activated carbon. Also conceivable is a production of the heat transfer body 28 from a composite material, in particular a fiber composite material. An example is a CC (carbon-carbon) material comprising pyrolyzed viscose fibers embedded in a phenolic resin.

Due to the porous nature of the heat transfer body 28 In the drawing, not shown in detail passages of small cross-section of the heat transfer medium 14 can be flowed through.

The specific surface of the heat transfer body 28 is very large due to the porous nature. For example, when using a CC material, the specific surface area may be about 1,000,000 m ² / m ³ to 5,000,000 m ² / m ³ . With an overall compact design of the fluid heater 10 has the heat transfer body 28 thus a very large of the heat transfer medium 14 contactable inner surface on.

The fluid heater 10 further comprises an electromagnetic excitation device 30 , The exciter device 30 includes a coil 32 , which is designed here as a cylindrical coil. A power supply 34, which is part of the fluid heater 10 or the exciter device 30 can be, stands with the coil 32 in operative connection, to apply these with electrical energy.

windings 36 the coil 32 are around the fluid channel 12 around at its widening section 26 guided. The sink 32 extends in the flow direction 16 over the entire length of the heat transfer body 28 , The heat transfer body 28 is a kind of core of the coil 32 ,

An isolation medium 38 is between the coil 32 and the wall 18 arranged. The isolation medium 38 is electrically and thermally insulating and in the form of an insulating layer on the fluid channel 12 applied. With insulating wall 18 can the separate isolation medium 38 omitted.

The sink 32 is with the heat transfer body 28 inductively coupled. When applying the coil 32 with alternating current induced by this magnetic alternating field in the heat transfer body 28 Eddy currents. This causes the heat transfer body 28 heated. That the passages of the heat transfer body 28 flowing heat transfer medium 14 is heated.

The inductive coupling of energy into the heat transfer body 28 allows a fast response time of the fluid heater 10 , Due to the low relative to the surface to be heated mass of the heat transfer body 28 can heat efficiently to the heat transfer medium 14 be discharged and this heated. The fluid heater 10 has a high efficiency.

In addition, there is a compact design with at the same time structurally simple production. This allows the fluid heater 10 to manufacture with low production costs. At the same time, there is the possibility of simple scaling by serial or parallel arrangement of fluid heaters 10.

The fluid heater 10 can be used in many different devices 100, for example, for heating water in the sanitary area, in vending machines or as a heating module in heating systems. These can be heating systems of motor vehicles, in which case electric vehicles or hybrid vehicles should be emphasized. For gaseous heat transfer medium 14 is a use in electric heating ventilation, drying equipment, wind tunnels or burners conceivable.

1 shows schematically the use of the fluid heating device 10 in such, by a dashed line 102 symbolized device according to the invention 100 , The fluid heating devices explained below could alternatively or additionally be provided by the device 100 includes his.

The device 100 can be a schematically represented consumer 104 include, which the heated heat transfer medium 14 can be supplied. The consumer 104 can, for example, with reference to the above-mentioned uses of Fluidheizvorrichtung 10 be, for example, a nozzle or include a blower or a pump unit.

The device 100 may be a controller 106 and preferably a delivery unit 108 include, which are also shown schematically. The control device 106 can with the delivery unit 108 and / or the consumer 104 be coupled. Preferably, the controller is 106 with the power supply device 34 coupled. There is, for example, the possibility of the volume flow of the heat transfer medium 14 passing through the fluid channel 12 flows, by controlling the delivery unit 108 to control and / or to regulate. Alternatively or additionally, that of the heat transfer body 28 to the heat transfer medium 14 transmitted energy by controlling the power supply device 34 controlled and / or regulated.

The magnetic susceptibility of the isolation medium 38 is preferably smaller than that of the heat transfer body 28 to its inductive coupling with the coil 32 not to interfere.

The heat transfer body 28 can be made of an electrically conductive material and with the power supply device 34 be coupled. This allows the heat transfer body 28 to heat by applying electrical current as ohmic heating element to additional energy to heat the heat transfer medium 14 provide.

An in 2 illustrated preferred embodiment of the fluid heater according to the invention is denoted by the reference numeral 40 busy.

In the fluid heater 40 is the heat transfer body 28 designed as a sleeve 42 having a bottom wall 44 and a side wall protruding therefrom 46 includes. The bottom wall 44 is upstream of the heat transfer body 28 arranged, based on the flow direction 16 the incoming heat transfer medium 14 , The sleeve 42 is aligned coaxially with the fluid channel 12.

At the bottom wall 44 is the heat transfer body 28 preferably free of passageways. Between the side wall 46 and the wall 18 is an annular space 48 arranged. The inflowing heat transfer medium 14 can in the broadening section 26 will flow in from the bottom wall 44 in the gap 48 then redirects and then the passages in the sidewall 46 flow through (arrows 50 ). Subsequently, the heat transfer medium flows 14 from the sleeve 42 in the discharge section 24.

The heat transfer body 28 may be configured in terms of the material and the nature of the passages as the heat transfer body 28 the fluid heater 10 , so that reference can be made in this regard to the above statements.

One in the 3 and 4 illustrated preferred embodiment of the fluid heater according to the invention is denoted by the reference numeral 60 busy.

In the fluid heater 60 is the fluid channel 12 configured as a flat channel, which has a rectangular cross-section. The broadening section 26 not applicable, the supply section 22 and the delivery section 24 are connected to each other via a heat transfer body 28 receiving middle section 62 connected.

The heat transfer body 28 in the fluid heater 60 is like the embodiment 10 positive fit in the interior 20 of the fluid channel 12 arranged, extending over the length of the middle section 62 extends.

The exciter device 30 includes in the embodiment 60 a coil 64 , which is designed as a flat coil. The sink 64 is arranged laterally next to the wall 18, wherein they are in a housing 66 can be caught. Alternatively, it is conceivable that windings 68 the coil 64 the wall 18 contact or that the isolation medium 38 between the windings 68 and the wall 18 is arranged.

The sink 64 is arranged on the broad side of the (flat) fluid channel 12. It can be provided that the excitation device 30 another coil 70 includes on the coil 64 opposite side on the fluid channel 12 is positioned. This is in 3 represented by dashed lines.

That from the coil 64 generated alternating magnetic field passes through the heat transfer body 28 transverse to the flow direction 16 , so that in this case, too, an inductive coupling of the excitation device 30 with the heat transfer body 28 consists. The heat transfer body 28 can be configured in a corresponding manner as the heat transfer body 28 the fluid heater 10 ,

An in 5 illustrated advantageous embodiment of a fluid heating device according to the invention is denoted by the reference numeral 80 busy.

In the fluid heater 80 are in the heat transfer body 28 crossings 82 in the form of channels 84 educated. The channels 84 are for example through holes in the heat transfer body 28 executed. The channels 84 run along the flow direction 16 ,

In addition, it can be provided that the heat transfer body 28 For example, as in the fluid heater 10 , has a porous nature and thereby intrinsic passages for the heat transfer medium fourteenth

One with the reference number 90 proven advantageous embodiment of a fluid heating device according to the invention is in 6 shown.

In the fluid heater 90 forms the heat transfer body 28 a recording room 92 , In the recording room 92 is a variety of free-flowing spherical heat transfer elements 94 positioned. The heat transfer elements 94 are present in a dense sphere packing in the receiving space 92 arranged, with the heat transfer elements 94 touch. Gaps between the heat transfer elements 94 make passageways 96 for the heat transfer medium 14 , In addition, it can be provided that the heat transfer elements 94 For example, as in the fluid heater 10 , have a porous nature.

Mutual contact of the heat transfer elements 94 is with regard to an electrical contacting of the heat transfer body 28 advantageous. This gives the possibility of electric current through a plurality of contacting heat transfer elements 94 to conduct, so that the heat transfer body 28 can also act as an ohmic heating element.

7 schematically shows a device according to the invention 110 , which may be, for example, a thermo-electric engine. The device 110 includes one with the reference numeral 112 proven advantageous embodiment of a fluid heating device according to the invention.

The fluid heater 112 is similar to the fluid heater 40 according to 2 designed. However, the delivery section is omitted 24 so that the widening section 26 end on the fluid channel 12 is arranged. The heat transfer body 28 is also designed sleeve-shaped, but it has on the output side a cross-sectional constriction 114 on. The cross-sectional constriction 114 forms a nozzle 116 , for example in the form of a Laval nozzle.

As a consumer 104 is an expansion nozzle 118 provided, the outflow to the fluid heater 112 is connected and thereby with the heated heat transfer medium 14 can be applied.

In the device 110 is the heat transfer medium 14 in particular a gas and preferably an inert gas. That over the heat transfer body 28 heated gas can to achieve the highest possible specific momentum through the nozzle 116 flow and then flow out via the expansion nozzle 118.

The volume flow of the gas is, for example, by means of the control device 106 via the delivery unit 108 controlled and / or regulated. This allows the pressure range and power range of the fluid heater 112 to set the combustion chamber formed.

The device 110 For example, satellites could be used on satellites to provide significantly greater thrust relative to an ion engine. With regard to time savings and / or fuel savings and increased flexibility in the optimization of the satellite orbit, such a device can 110 prove advantageous, for example when introducing the satellite in the example geostationary target orbit. In this transfer phase, the satellite has not yet started operation, but there is already considerable power available through existing solar panels that can be used for the thermo-electric engine.

A constructive to the device 110 similar device according to the invention is in 8th shown schematically and there by the reference numeral 120 busy. The device 120 is for example a burner that can be used in particular for cutting operations. The device 120 includes one with the reference numeral 122 occupied fluid heating device according to the invention.

The fluid heater 122 is structurally constructed as the fluid heater 112 and also includes those about the cross-sectional constriction 114 formed nozzle 116 on the output side of the heat transfer body 28. As a consumer 104 For example, a nozzle 124 be provided.

As heat transfer medium 14 a gas and in particular an inert gas is used. The hot gas zone may in this way consist of a defined individual gas, unlike conventional burners with a gas mixture, so that even critical materials can be targeted locally heated or cut. When using an inert gas, oxidation processes of the heat-heated heat transfer body become 28 avoided. By using, for example, carbon-based materials, extreme temperatures can be achieved thereby.

In the present case, the device comprises 120 Conveniently in addition a feeder 126 , The feeder 126 is advantageously from the controller 106 controllable to selectively supply a further gas downstream of the fluid heating device 122 to control and / or to settle. Schematically, supply lines are in the drawing 128 represented, through which the further gas for defined mixing in the heated heat transfer medium 14 can be supplied to achieve the desired hot gas effect.

At one in the 9 schematically illustrated and designated by the reference numeral 130 fluid heating device is the heat transfer body 28 for example in the form of a sleeve 132 designed. The sleeve 132 includes a bottom wall 134 and a side wall 136 , where the bottom wall 134 positioned downstream and free of passageways. Upstream is the sleeve 132 open so that over the feed section 22 inflowing heat transfer medium 14 in the from the sidewall 136 enclosed section of the interior 20 can flow in.

The sink 32 the exciter device 30 is in the interior 20 positioned within the sidewall 136 enclosed section. The sink 32 is a cylindrical coil that is coaxial with the sleeve 132 and aligned with the fluid channel 12.

That over the feed section 22 inflowing heat transfer medium 14 enters the sleeve upstream 132 and flows around the windings 36 the coil 32. The coil 32 can be convectively cooled in this way. Subsequently, the heat transfer medium flows transversely and in particular perpendicular to the direction of extension of the fluid channel 12 through passages in the side wall 136 (arrows 138 ) and enters a gap 140 between the heat transfer body 28 and the wall 18 one. The heat transfer medium 14 flows laterally on the heat transfer body 28 over and enters the delivery section 24 ,

The fluid heater 130 is characterized by a particularly compact design.

LIST OF REFERENCE NUMBERS

10

fluid heating device

12

fluid channel

14

Heat transfer medium

16

flow direction

18

wall

20

inner space

22

feeding section

24

dispensing portion

26

widening section

28

Heat transfer body

30

excitation device

32

Kitchen sink

34

Power supply means

36

winding

38

insulation medium

40

fluid heating device

42

shell

44

bottom wall

46

Side wall

48

gap

50

arrow

60

fluid heating device

62

middle section

64

Kitchen sink

66

casing

68

winding

70

Kitchen sink

80

fluid heating device

82

passage

84

channel

90

fluid heating device

92

accommodation space

94

Heat transfer element

96

passage

100

contraption

102

line

104

consumer

106

control device

108

delivery unit

110

contraption

112

fluid heating device

114

Cross-sectional narrowing

116

jet

118

expansion nozzle

120

contraption

122

fluid heating device

124

jet

126

feeder

128

supply line

130

fluid heating device

132

shell

134

bottom wall

136

Side wall

138

arrow

140

gap

Claims (20)

Fluid heating device, comprising a fluid channel (12) for passing a fluid heat transfer medium (14), arranged in or on the fluid channel (12) or formed by this heat transfer body (28) from the heat transfer medium (14) through-flow passages (82, 96) and an electromagnetic Excitation device (30), which is inductively coupled to the heat transfer body (28). Fluidheizvorrichtung after Claim 1 , characterized in that the exciter device (30) has at least one coil (32, 64, 70). Fluidheizvorrichtung after Claim 1 or 2 , Characterized in that surrounding said solenoid (32) is a coil (32) a wall (18) of the fluid channel (12) is provided and / or that as a coil (64, 70) has a laterally adjacent to a wall (18) of the fluid channel ( 12) arranged coil (64, 70) is provided, in particular a flat coil (64, 70). Fluid heating device according to one of the preceding claims, characterized in that the heat transfer body (28) is made, at least partially, of a porous or foam-like material, the passages being formed by the porous or foam-like nature of the heat transfer body (28). Fluid heating device according to one of the preceding claims, characterized in that the passages (82) are designed as channels (84), for example as bores, in the heat transfer body (28). Fluidheizvorrichtung according to any one of the preceding claims, characterized in that the heat transfer body (28) comprises at least one of the following materials or consists of at least one of the following materials or is made: - a metallic material; a ceramic material; - A composite material, in particular a fiber composite material; Carbon or a carbonaceous material, for example graphite, carbon felt, carbon foam, activated carbon, silicon carbide; - Of a sintered material. Fluid heating device according to one of the preceding claims, characterized in that the fluid channel (12) is designed round in cross-section or that the fluid channel (12) is designed as a flat channel. Fluidheizvorrichtung according to any one of the preceding claims, characterized in that the heat transfer body (28) in the fluid channel (12) is arranged, in particular transversely to a flow direction (16) of the heat transfer medium (14) positively received in the fluid channel (12). Fluid heating device according to one of the preceding claims, characterized in that the passages (82) of the heat transfer body (28) along a flow direction (16) of the heat transfer medium (14) through the heat transfer body (28) are aligned. Fluidheizvorrichtung according to any one of the preceding claims, characterized in that the heat transfer body (28) is sleeve-shaped and a gap (48) between a wall (18) of the fluid channel (12) and the heat transfer body (28) is provided, that preferably the passages across or perpendicular to the flow direction (16) of the heat transfer medium (14) are aligned and the heat transfer body (28) upstream of passages, wherein the heat transfer body (28) via the intermediate space (48) with the heat transfer medium (14) can be acted upon. Fluid heating device according to one of the preceding claims, characterized in that the heat transfer body (28) forms a wall (18) of the fluid channel (12). Fluid heating device according to one of the preceding claims, characterized in that the heat transfer body (28) forms a receiving space (92) and arranged therein free-flowing heat transfer elements (94) which are inductively coupled to the exciter device (30) and between which the passages (96 ) forming gaps are present. Fluid heating device according to one of the preceding claims, characterized in that the heat transfer elements (94) are received touching each other in the receiving space (92) and / or that the heat transfer elements (94) are spherical. Fluidheizvorrichtung according to any one of the preceding claims, characterized in that the heat transfer body (28) or the Heat transfer elements (94) is / are ferromagnetic, ferrimagnetic or paramagnetic. Fluid heating device according to one of the preceding claims, characterized in that the heat transfer body (28) or the heat transfer elements (94) made of an electrically conductive material and coupled to a power supply device (34) or are coupled to pass an electric current through the heat transfer body (28) or the heat transfer elements (94). Fluid heating device according to one of the preceding claims, characterized in that the heat transfer body (28) or the heat transfer elements (94) have a specific surface area of at least 1,000 m ² / m ³ , preferably at least 100,000 m ² / m ³ , more preferably at least 1,000,000 m ² / m ³ . Fluid heating device according to one of the preceding claims, characterized in that at least one of the following is provided: - an electrical insulation medium (38) between the excitation means (30) and the heat transfer body (28), wherein the insulation medium (38) has a lower magnetic susceptibility than the heat transfer body (28); and - a thermal insulation medium (38) between the excitation means (30) and the heat transfer body (28). Fluidheizvorrichtung after Claim 17 , characterized in that the electrical and the thermal insulation medium (38) are identical. An apparatus (100; 120; 140) comprising at least one consumer (104) having at least one fluid heating device (10; 40; 60; 80; 90; 112; 122) according to any one of the preceding claims, wherein the at least one consumer (104) the heat transfer medium (14) heated by the at least one fluid heating device (10; 40; 60; 80; 90; 112; 122; 130) can be supplied. A method for heating a fluid heat transfer medium, wherein the method, the heat transfer medium is arranged in a fluid passage or formed by the heat transfer body and is heated by this, wherein the heat transfer body is inductively coupled to an exciter device.

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