DE2355411A1 - HEAT EXCHANGER - Google Patents

Description

The invention relates to a heat exchanger in which the heat is transferred from one fluid to another fluid, particularly a boiler for a central heating system and a chemical heat exchanger.

Although many types of heat exchangers are known, there always is the need to reduce the overall size of the device in order to facilitate its installation in relatively small spaces, e.g. in apartment kitchens. It is also desirable that the heat exchanger be robustly constructed and in the Should be able to heat a fluid, e.g. a liquid, to high temperatures. The invention is upon it directed to create such a heat exchanger.

The invention consists in that a line part for a fluid with one or more flow conductors

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is seen, of which at least parts run parallel to each other, and that at least the parallel parts of the line part with thermally conductive, elongated or porous sheet metal material stand in touch.

The line part for the fluid preferably consists of a plurality of independent flow conductors. But if it is if desired, the conduit portion for the fluid could be formed by a single conduit which is so bent is that it is in the form of a plurality of sine waves. Usually the flow guides consist of tubes, which are preferably have a circular cross-section. The tubes can be connected to a common upper chamber and a common lower chamber be connected. The upper chamber and the lower chamber can be divided so that the fluid from the lower chamber through a first tube set into the upper chamber, through a second tube set back into the lower one Chamber, through a third set of tubes back into the upper chamber and through a fourth set of tubes back into the lower Chamber flows. The thermally conductive material preferably runs between the parallel parts of the line part and in this way acts to interrupt the flow of fluid flowing over the outer surface of the conductor part. This fluid is therefore in a turbulent state, which allows for good heat transfer between a first fluid in the ladder portion and a second fluid flowing over the outside of the ladder portion flows, is advantageous. In addition, the thermally conductive material increases the surface area over which the heat can be transferred. Usually a hot fluid flows over the outside of the conductor part, and the heat is transferred from this fluid to a cold Sfcrö-

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transfer medium ^ which passes through the ladder part. In Bollern for central heating systems the hot Fluid usually formed by a gas and that cold fluids usually water. However, the heat exchangers according to the invention can also be provided for To transfer heat from one gas to another or from one liquid to another liquid.

The elongate heat conducting material is preferably made of metal 'tal'ldraht, the "example has a circular cross-section" It could also be provided _s that the elongate heat conducting material of a metal braid or flat strip is "The heat-conducting porous layer material can. A metal mesh or a gauze layer be For example, copper, steel or various alloys can be used as metals.

When the thermally conductive material is arranged around the conduit part j then the whole arrangement is coated with metal j, e.g. by dip soldering or by spray metallization. The metal coating forms a connection at the points where you can see the thermally conductive material itself and the The flow _{conductor touches s} so that good heat conduction paths are thereby formed between the flow conductors and the thermally conductive material.

The thermally conductive material _9, for example wire _9, can be braided or woven around the parallel parts of the conduit part for the fluid in such a way that it has a parallel part below the next two. Parts, .over the following part j under the next two parts, etc. runs around the line position. In another embodiment, can. the thermally conductive material over a parallel part of the • line part, under »the thickest part through ₉ over

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the next part away, under the next part, etc. around the line part. It can too other configurations may be provided if so desired. '.

The conduit part can be designed in various shapes, although its external shape is generally a circular cross-section, has a square or rectangular cross-section.

To the heat transfer between the flowing through the line part To further improve fluid and the fluid flowing over the conduit part can all be great axial joints of the entire device of the line part and the thermally conductive material to be filled with solid material that acts as a deflection device; serves. The solid material is hard-soldered, welded, or soft-soldered or connected in any other way to the heat exchanger, e.g. with the help of the dip soldering described above. The solid material can be formed into particles, spheres, rods, or angles be. Typical examples of the solid material preferably used in the invention are stainless metals, such as copper, stainless steel and aluminum. The solid material should have a high coefficient of thermal conductivity and do not melt or otherwise decompose prematurely below the working temperature of the heat exchanger. Of course, the same requirements are placed on the material selected for the flow guides.

If the hot fluid is a hot gas, e.g., natural gas, then a pressure regulator can be provided which ensures that the gas is always fed to the burner at a certain constant pressure. The establishment

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this pressure regulation is particularly desirable in cases in which natural gas is used, as sometimes large ones Pressure fluctuations occur.

The heat exchanger according to the invention can be equipped with an ignition device to ignite the gas. The gaseous fluid can consist of a mixture of air and natural gas exist. Gases other than natural gas can of course be used if desired, but natural gas will be used in the subject of the invention-preferred because it is in available to most industries and households. So that sufficient air is mixed with the natural gas, has The heat exchanger usually has a fan that draws air into a device to mix it with the natural gas before this is ignited. Flame arrestors can be provided if the ignited gaseous material should tend to be at undesired locations of the device to burn.

The gases can be fed in such a way that they burn continuously, but with different strengths, so that a control over the amount of ignited gas can be exerted and thus indirectly a control of the temperature of the fluid to be heated. On the other hand, the gas supply can also be turned on or be parked if necessary, e.g. by a suitable thermostat so that the fluid to be heated is kept at a certain temperature> Typical examples of suitable ignition devices are spark ignitors or gas control flames. -..- ..

Hot fluids discharged from the heat exchanger according to the invention can be re-circulated around the

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to support further heating process. In addition, the outside of the heat exchanger can be covered with an appropriate insulating material must be provided so that heat losses are kept to a minimum. If a heat exchanger according to the invention in a central heating system is used, it is equipped with a suitable fire draft and in a known manner connected to appropriate radiators.

Further features, advantages and details of the invention emerge from the following description of the embodiment examples based on the drawing. Show in it:

.Fig.l a longitudinal section through a first embodiment of the heat exchanger according to the invention, with some vertical tubes omitted for clarity;

2 shows a partial cross section through the heat exchanger according to Pig.l, in which in particular a preferred wire mesh or wire mesh is shown, and

Fig. 3 is a partial cross-section similar to Fig.2, in which however, a different wire mesh or wire mesh is shown.

In FIGS. 1 and 2, a heat exchanger 2 is shown which has a line part for a fluid 3 (see FIG. 2) with flow line tubes 4 arranged parallel to one another. The line part 3 is cylindrical, and wires 6 are braided around the tubes 4. As can be seen most clearly in FIG. 2, the different wire lengths each run over the outside of a tube 4, then over the inside of the next two tubes

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then again over the outside of the following pipe 4, then over the inside of the two adjoining tubes Pipes 4 etc. over the whole line part 3 · Through this Arrangement, a fairly contiguous or continuous area is formed on the inside of the line part 3, and there is a corresponding number of wire crossing points 8 between the inside and the outside of the line part 3 · To complete the arrangement of the wire 6 around the line part 3, another wire 6 is placed around the Outside of the part 3 wrapped around, so that a fairly coherent or uninterrupted outer surface is formed. The whole arrangement of the part 3 and the wire 6 is soldered together, so that good heat conduction paths between the wire 6 and the tubes 4 are created. The soldering is done by that a copper paste on the line part 3 and the Wire 6 is applied, and that the whole assembly is then placed in an oven. The wiring can thereby be made that each tube 4 is arranged on a not shown in the drawing and on a base plate The mandrel is attached and the wire 6 is guided symmetrically around the tubes 4. The end product then makes a Soldered device that prevents the passage of gas through the small holes in the one formed by the wire 6 Tissue allows. ·

The tubes 4 have an upper chamber 10 and an annular one lower chamber 12 in connection. The lower chamber 12 is with three plates 30, 31 and 32 in three sections A, B and C divided. The upper chamber 10, which extends across extends the upper part of the heat exchanger 2 is with the help a plate 33 divided into the two sections D and E. The lower chamber 12 is also equipped with a Plüssig-

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Keitseinlaß l4 and a liquid outlet 16 equipped.

The heat exchanger 2 has a combustion chamber 18, e.g. consists of gases and is equipped with a gas igniter 20 The walls of the combustion chamber 18 form a flame holder and are provided with holes 22 through which the to be ignited Gases escape. As can be seen, a gas flame arrester 21 is arranged in the combustion chamber 18. A housing 24 surrounds the device formed from the line part 3 and the wire 6 and forms a chamber 26.

When the heat exchanger 2 according to the invention in a central heating system is built in, so there is no fluid to be heated made of water, and the hot fluid that gives off its heat to the water is gas. The water flows into the heat exchanger 2 through the liquid inlet 14 and flows through tubes 4a in section B of the lower chamber 12 to section D of the upper chamber 10. The water in section D of the chamber cannot enter the Section E flow because sections D and E are separated from one another by plate 33. The water must therefore flow along the tubes 4b, which are connected to the section A of the lower chamber 12. are connected. The water in section A of the lower chamber 12 is with the help of Plates 30 and 32 deflected and can only flow along the pipes 4c, which direct the water back into the upper chamber 10, but this time in section E. The water in section E can now only go along the pipes 4d to section C in the lower chamber 12. Then the water flows from this section C from the Heat exchanger 2 via outlet 16.

During the time in which the water through the heat exchange

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shear 2 flows, a mixture of natural gas, and air is in the Combustion chamber 18 initiated, from where it flows out through the holes 22 and is ignited by means of the gas igniter 20. the Walls of the combustion chamber 18 act in such a way that they remove the flame of the ignited gas and that around its outside Retain air and a gauze gas flame arrester 21 prevents any flame from entering the combustion chamber 18 strikes back into the gas pipe. The hot gases flow on both sides of the liquid line part 3 along .. They flow through the holes in the wire mesh between the tubes 4 and get into the Kamnier 26, from where they finally leave the heat from ph ei »2 through an outlet 28 if they are not circulated again. on this will be in the liquid line part 3 water "is heated by the hot gas mixture that brushes along the outside of the pipes.

ϊη of FIG. 3, a liquid conduit part is shown which is constructed similarly to that of FIG. In the subject of Figure 3, the wire 66 runs; however, ^around <each pipe l \ k , so that the _{pattern shown in s} in FIG. 3 arises, further

66 _: is then continuously around / the outside of the ^{tube It 1} I Um §in, e _; np ^ timslen heat transfer between & ^e Q Qases, which lie around the outer tex ^ sfite of the pipes k§ , ruraström.en, and the, Wass.er ^ das, flows through the pipes Ι | ^, to e, rr, § tph ^ n, are Vlärmetau ^ iersta? igen _: TQ VQEgesphen. Dig in Fig. 3 shown Apordnuiig is in plpieher? Wei ^ e wi§ d | e % Q ö ^ r figv2

e arrangement with copper. y> goes out. The | te? ^ Ht .66 \, the k unc | d | e rods: 70 fig ^ p da-bep pAW ^l ^ §i ^b ^^ t '? ^a 6 ^e ^ A ^e direction .. Ir ^ cleirt prah ^ ggwebe sinci ^ leiwei ^ f -fnunger \ available; which it ^ ulas »se | v that iie: | ße Qas-e, U ^ dji ^ Ro | i, pe M ^

and its warmth, of the water flowing _{in the Ro ^ rie.n a}

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Ser can deliver.

The heat exchanger 2 can be constructed so compactly that it is only 6.5 inches (165 mm) in diameter and 5 inches (127 mm) deep. Nevertheless, such a heat exchanger delivers an output of 55,000 BTU / Hr (I386O kcal / h), which corresponds to an efficiency of 80 % .

It can also be provided that further deflection devices are inserted into the V-shaped interspaces which are formed by the wire 66 on the outside of the round part of the tubes 44 (see Figure 3) open outward, thereby helping to deflect the hot gases that flow through the holes in the wire mesh 66 and around the tubes 44.

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Claims (10)

Patent nt claim 1. Heat exchanger in which the heat is transferred from one fluid to another fluid, in particular boilers for a central heating system and chemical heat from rather ge advises, thereby geke η. η indicates that a line part (3) for a fluid with one or more flow guides ^{(4) is provided, of which at least parts (1 JaJ 1} Jb ₅₁ ¹ Jc ,, ¹ ^ parallel to each other • run, and that at least the parallel parts of the line part with thermally conductive, elongated or porous Layer material in contact ". 2. Heat exchanger according to claim 1, characterized in that the line part (3) is formed by several independent St.römungsleitern ( ¹ Ja ₉ ¹ Jb ₉ ¹ JCj ¹ Id). 3. Heat exchanger according to claim 2, characterized in that the flow guides are tubes, which are connected to a common upper chamber (10) and a common lower chamber (12). 4 «, heat exchanger according to claim 3, characterized in that the upper. Chamber. (10) and the un- 'tere chamber (12) divided in such a way that the flow are _s' - 409,820 / 0.8 63 medium from the lower chamber through a first tube set (4a) into the upper chamber (10), through a second tube set (4b) back into the lower chamber, through a third .Rohrsatz ( ¹ Ic) back into the upper chamber and through a fourth set of tubes (Ha) flows back into the lower chamber. 5. Heat exchanger according to one of claims 1 to 4, characterized in that the thermally conductive material (6,66) between the parallel parts of the line • part (3) passes through. 6. Heat exchanger according to claim 5, characterized in that the thermally conductive material of a metal wire is formed, which is wound around the parallel parts of the line part (3). 7. Heat exchanger according to claim 6, characterized in that the line part and the thermally conductive Material are coated with a metal. Bi heat exchanger according to one of claims 1 to 7 »characterized in that outside the flow conductors are arranged parallel to these heat exchanger rods (70). 9. Heat exchanger according to claim 8, characterized in that deflection plates are provided. 10. Heat exchanger according to one of claims 1 to 9 »characterized in that the heat exchanger is designed as a central heating device and a device for regulating the gas pressure and for ignition of the gas. 409820/0863 - 12 - Empty soap