Flat tube heat exchanger

Abstract

The invention relates to a flat tube heat exchanger, in particular for high-temperature flat tube heat exchangers for gaseous media, comprising a closed housing (5) with a tube bundle space (50) and a tube bundle arranged in the tube bundle space (50) of the housing (5), which tube bundle comprises a plurality of flat tubes (2), wherein in the flat tubes (2) and in the tube bundle space (50) between the flat tubes (2) corrugated strips (3, 6) are arranged, which have wave crests (30, 60) and wave troughs (31, 61) extending in the longitudinal direction of the flat tubes (2), wherein the wave crests (30, 60) and the wave troughs (31, 61) abut at the flat sides (200) of the flat tubes (2) on the inside or on the outside, and wherein a device is provided in order to load the housing (5) from the outside at least in the region of the tube bundle space (50) with a surface pressure which is higher than the pressure (p1, p2) of a medium conducted in the flat tubes (2) or around the flat tubes (2).

Description

Technical Field

[0001] This invention relates to a flat tube heat exchanger, particularly a high-temperature flat tube heat exchanger for gaseous media. Background Technology

[0002] Flat-tube heat exchangers are generally known. For example, EP 2 584 301 A1 describes a high-temperature flat-tube heat exchanger for gaseous media, which has a closed shell with two tube bottoms at two opposing sides. These tube bottoms divide the shell into an inlet-side collection space, a tube bundle space, and an outlet-side collection space, which contains a tube bundle consisting primarily of flat tubes with straight, circular or polygonal ends. The tube bundle space has three regions: two transverse flow regions configured at the interface of the tube bundle space, and a longitudinal flow region configured between these transverse flow regions. The flat-tube heat exchanger described therein can be used under high-temperature diffusion and frequent temperature changes without the risk of stress cracking. Such flat-tube heat exchangers have been repeatedly demonstrated, especially at gas inlet temperatures up to 1100°C.

[0003] The efficiency of a flat-tube heat exchanger depends, among other things, on the number of flat tubes used. Typically, flat-tube heat exchangers are used at approximately 75% efficiency. For a conventional flat-tube heat exchanger, to further increase the efficiency from approximately 75% to approximately 90%, the number of flat tubes must be roughly tripled for the same throughput. This is generally likely to be economically impractical. Summary of the Invention

[0004] The objective of this invention is to provide a flat tube heat exchanger with improved efficiency.

[0005] This task is addressed by a flat-tube heat exchanger, particularly for gaseous media, comprising: a closed shell having a tube bundle space, and a tube bundle arranged in the tube bundle space of the shell, the tube bundle comprising a plurality of flat tubes, wherein a corrugated strip is arranged in the flat tubes and in the tube bundle space between the flat tubes, the corrugated strip having troughs and crests extending along the longitudinal direction of the flat tubes, wherein the troughs and crests abut against the flat sides of the flat tubes, either internally or externally, and wherein a device is provided to apply a surface pressure to the shell from the outside, at least in the region of the tube bundle space, the surface pressure being higher than the pressure of the medium guided in or around the flat tubes, particularly about 1 bar to about 4 bar higher.

[0006] By means of a corrugated belt, the area used for heat transfer of the medium guided in or through the flat tube, also known as the transfer area, can be more than doubled. At the same time, the hydraulic diameter through and around the flat tube is reduced, and as a result, the heat transfer coefficient increases inversely in the case of countercurrent operation.

[0007] Deformation of the flat tube, which could lead to potential contact losses, is reliably prevented by means of a device for applying surface pressure to the shell, such deformation being caused, for example, by the temperature or pressure of the medium guided within the flat tube. Therefore, the flat tube heat exchanger is suitable for operation not only with a high pressure differential between the flat tube and the medium guided around it, but also with high temperature fluctuations, for example, during startup and shutdown.

[0008] In the context of this application, the phrase "in flat tubes" should not be interpreted as "in all flat tubes." More precisely, it is conceivable not only of a design in which only a portion of the flat tubes have corrugated strips, but also of a design in which all the flat tubes have corrugated strips. Similarly, in the context of this application, the words "a," "an," "a kind," etc., are used only as indefinite articles and should not be interpreted as numerals.

[0009] The housing typically has two collection spaces that allow the first medium to flow into and out of the flat tube. In the case of a tube bundle flowing in one direction, the collection spaces are located at opposite ends of the tube bundle space. To allow a second medium to enter and exit the tube bundle space, the tube bundle space interface is located at opposite ends or sides of the housing when viewed in the flow direction.

[0010] The tube described below is referred to as a flat tube, which is flat at least in the middle section between the two ends; that is, the tube has two flat sides facing each other and two narrow sides connecting the flat sides. In one design, the middle section of the flat tube has a stadium-shaped cross-section, which has two flat sides that are parallel to each other and two curved, for example, semi-circular, narrow sides connecting the flat sides. Here, a corrugated strip with a constant height can be used, the troughs and crests of which contact the flat sides. In another design, the longitudinally opposed ends of the flat tube have a cross-section different from the middle section, particularly a circular cross-section, a polygonal cross-section, etc., which is used to connect to the collection space.

[0011] In one design, the flat-tube heat exchanger is constructed as a rectangular arrangement with a block-shaped tube bundle space and multiple flat tubes arranged in rows and columns. In another design, the flat-tube heat exchanger is constructed as a circular arrangement with a cylindrical tube bundle space having a circular or polygonal cross-section. In the circular arrangement, the heat exchanger is constructed as an annular heat exchanger in one design, wherein the flat tubes are arranged along multiple concentric rings of different diameters.

[0012] In one design, the corrugated strip has a sinusoidal, triangular, or sawtooth waveform. These waveforms share the common characteristic that the crests and troughs abut against the flat side only along narrow strips extending longitudinally, ideally linearly. This avoids or at least minimizes material buildup at the contact points that negatively impacts heat transfer. The waveform can be appropriately selected by those skilled in the art based on the application to achieve the desired increase in transfer area. It is also feasible to implement standard modules for flat tube heat exchangers, where flat tube heat exchangers with different dimensional designs of transfer surfaces are achieved by selecting suitable corrugated strips.

[0013] Depending on the material and wall thickness, the corrugated strip also serves as a support to resist deformation of the flat tube caused by the negative pressure of the medium guided within the flat tube relative to the medium surrounding it. In the design of a flat tube heat exchanger, the width of the corrugated strip is at least equal to the width of the flat side of the flat tube.

[0014] The height of the corrugated strip arranged in the flat tube is approximately equal to the height of the flat tube, wherein the corrugated strip and the flat tube, for example, have a height of about 2 to about 4 mm. In one design, the flat tube is expanded by pressure and / or temperature to insert the corrugated strip, wherein after the pressure or temperature is removed, the corrugated strip abuts against the flat side of the flat tube. In another design, the height of the corrugated strip arranged between the flat tubes is approximately equal to the spacing between the adjacent flat tubes, such that the crests and troughs of these corrugated strips abut against the flat sides of the adjacent flat tubes.

[0015] In one design, the crests and troughs freely abut against the flat side of the flat tube, meaning the corrugated strip and the flat tube are neither fused nor brazed or otherwise material-locked together. This eliminates the need for costly and expensive welding connections. Alternatively, the corrugated strip or flat tube can be made of a non-fusion-weldable or non-brazable material. Because the invention provides a device to apply surface pressure from the outside to the housing, at least in the region of the tube bundle space, this surface pressure is higher than the pressure of the medium guided in or around the flat tube, thus ensuring contact between the corrugated strip and the flat tube during operation even in the absence of a material-locked connection between the corrugated strip and the flat tube.

[0016] In one design, the device includes an outer housing that receives the housing, wherein the outer housing surrounds the housing at a distance, at least in the region of the tube bundle space, while retaining a pressure space. Here, the outer housing is designed and arranged such that it can receive fluid in the pressure space, the pressure of which is higher than the pressure of the medium in the internal space of the housing, particularly by about 1 bar to about 4 bar. The design of the outer housing can be appropriately carried out by those skilled in the art according to the application. In one design, thermal insulation is provided around the housing to prevent or at least reduce the temperature rise of the fluid in the pressure space between the housing and the outer housing.

[0017] In one design, the outer casing is designed as a pressure vessel with interfaces for media input and / or media output, wherein the pressure within the pressure vessel can be regulated by means of the media input and / or media output. In the context of this application, a closed container without or at least without significant deformation for receiving fluid under pressure is referred to as a pressure vessel, wherein the pressure inside the pressure vessel is higher than the ambient pressure.

[0018] In an alternative design, the device comprises a beam pair and / or plate pair having two bend-resistant beams and / or plates movable relative to each other and connected by means of tie rods, wherein at least one section of the housing is arranged between the beams and / or plates of the beam pair and / or plate pair. The beams or plates of the beam pair and / or plate pair are connected by means of tie rods and can be clamped together with a defined force by means of suitable means. As mentioned above, in the context of this application, the words “a,” “an,” “a,” etc., are used only as indefinite articles and should not be construed as numerals. Here, the device can include, in particular, more than one beam pair and / or plate pair. The number of beam pairs and / or plate pairs can be appropriately selected by those skilled in the art according to the application. This results in a cost-effective device for applying surface pressure to a housing, which is particularly suitable for applications where there is no or only moderate overpressure in and around the flat tube. For example, flat-tube heat exchangers with such devices can be used in situations where polluted air or exhaust gases are burned in the heat.

[0019] In one design, the beam pairs and / or plate pairs act directly on the shell. In an advantageous design, the equipment further includes an outer shell, wherein the outer shell surrounds the shell at a distance, at least in the region of the tube bundle space. The force applied to the outer shell by the beam pairs and / or plate pairs is transferred to the shell. In one design, this is achieved by means of an incompressible fluid present in the outer shell. In an advantageous design, pressure struts for force transfer are arranged between the outer shell and the shell. The outer shell can be loaded from the outside by means of the beam pairs and / or plate pairs, wherein the load is transferred to the shell by means of the pressure struts. Here, in one design, thermal insulation is additionally provided between the outer shell and the shell.

[0020] In one design, the corrugated strip is at least partially coated with a material that acts as a catalyst. For example, when using a flat-tube heat exchanger in a reactor, this type of coating is advantageous for endothermic processes, such as hydrocarbon reforming, or for exothermic processes, such as the synthesis of synthetic fuels. Especially when the corrugated strip freely rests against the flat tube, it can be a coating that is unrestricted in terms of weldability. Here, in the design of the flat-tube heat exchanger, the corrugated strip is coated only in the flat tube or only on the outside of the flat tube. In another design, the corrugated strip in the flat tube and the corrugated strip on the outside of the flat tube have different coatings.

[0021] In one design, a corrugated strip is incorporated into the flat tube, wherein the length of the corrugated strip along the longitudinal direction of the flat tube is less than or equal to the length of the middle section of the flat tube. Here, barring other measures, the flow through the flat tube with the corrugated strip is laminar.

[0022] In an alternative design, at least two corrugated strips are arranged in opposite directions along the longitudinal direction in the flat tube. This arrangement, with a 180° phase shift, is referred to as a reverse arrangement, where the crests and troughs of the corrugated strips are aligned with the troughs or crests of adjacent corrugated strips. This measure achieves vortices in the flow through the flat tube for improved heat transfer.

[0023] In one design, transverse ribs are arranged between two adjacent corrugated strips. Further vortices are achieved by means of these transverse ribs. In another design, the corrugated strips and transverse ribs are connected to each other. In yet another design, the corrugated strips rest freely against the transverse ribs.

[0024] In one design, the flat tube is composed of at least two flat tubes extending longitudinally. In another design, the flat tube is based on a tube having: a short section with a circular cross-section and a smaller diameter, and a section with a circular cross-section and a larger diameter. The section with the larger diameter can be flattened during a forming process, such as in a rolling process, particularly between cylindrical rolls. Subsequently, a corrugated strip can be inserted into the formed section, and the two mirror-symmetrically arranged flat tubes can be connected to each other, particularly by welding. Here, it is particularly feasible for applications with a large temperature range, for example up to 1000°C, to consist of flat tubes made of different materials. Attached Figure Description

[0025] Other advantages and aspects of the present invention will become apparent from the following description of embodiments of the invention, which are illustrated below with reference to schematic diagrams. Wherein:

[0026] Figure 1 A longitudinal section is shown of a flat tube for a flat tube heat exchanger, wherein a corrugated strip is arranged within the flat tube, the corrugated strip having crests and troughs extending along the longitudinal direction of the flat tube.

[0027] Figure 2 To follow Figure 1 The cross section of section line II-II shows the cross section according to Figure 1 flat tube,

[0028] Figure 3 To follow Figure 1 The cross section of section line III-III shows the cross section according to Figure 1 flat tube,

[0029] Figure 4 The longitudinal section shows the structure according to Figure 1 The tube bundle space of a flat tube heat exchanger with multiple flat tubes.

[0030] Figure 5 It shows according to Figure 4 A top view of the tube bundle space.

[0031] Figure 6 To follow Figure 4 The cross-section of section line VI-VI shows the cross-section according to Figure 4 The tubular space,

[0032] Figure 7 A first design of a flat-tube heat exchanger with multiple flat tubes is shown in longitudinal section, wherein the shell of the flat-tube heat exchanger is surrounded by a shell designed as a pressure vessel.

[0033] Figure 8 To follow Figure 7 The cross section of section line VIII-VIII shows the cross section according to Figure 7 Flat tube heat exchanger,

[0034] Figure 9 A second design for a flat-tube heat exchanger with multiple flat tubes is shown in longitudinal section, wherein the shell of the flat-tube heat exchanger is surrounded by an outer casing, and surface pressure is applied to the outer casing by means of multiple beams.

[0035] Figure 10 To follow Figure 9 The cross-section of the section line XX shows the cross-section according to Figure 9 Flat tube heat exchanger,

[0036] Figure 11 The perspective view shows an alternative arrangement of the corrugated belt, and

[0037] Figure 12 The cross-section shows the product according to Figure 11 A flat pipe with a corrugated strip arrangement. Detailed Implementation

[0038] In the following description of embodiments of the present invention, the same or similar components are referred to by uniform reference numerals.

[0039] Figures 1 to 3 With longitudinal section and along according to Figure 1 The two cross sections, II-II and III-III, show the flat tube 2, which is used for... Figures 1 to 3 Flat tube heat exchanger 1 not shown in the image (see also...) Figures 7 to 10 ).

[0040] The flat tube 2 has two ends 21, 22 and an intermediate section 20 located between the two ends 21, 22. The cross-section of the intermediate section 20 has a stadium shape, having two flat, parallel sides 200 and two curved, semi-circularly curved narrow sides 201 connecting the flat sides 200. The ends 21, 22 have a different cross-section from the intermediate section 20, for example a circular cross-section, which is used to connect to the collection space of the shell of the flat tube heat exchanger 1 (not shown).

[0041] Two corrugated strips 3 are arranged in the flat tube 2, more specifically in the middle section 20 of the flat tube 2. These corrugated strips have crests 30 and troughs 31 extending along the longitudinal direction L of the flat tube (see...). Figure 2 and Figure 3 In the illustrated embodiment, the two corrugated bands 3 have sinusoidal waveforms. The crests 30 and troughs 31 have the same shape. The upward bulge of the corrugated band 3 in the drawing plane is referred to as the crest 30, and similarly, it is conceivable that the downward bulge in the drawing plane is referred to as the crest.

[0042] The corrugated strips 3 shown have a constant height, and the crests 30 and troughs 31 contact the opposing inner surfaces of the flat side 200 of the flat tube 2. The width of the corrugated strips 3 is approximately equal to the width of the flat side 200.

[0043] Figure 1 The flat tube 2 shown consists of two flat tube fittings 2a and 2b extending longitudinally L, respectively. The flat tube fittings 2a and 2b are arranged mirror-symmetrically and welded together along weld seam 4. In the illustrated embodiment, the flat tube fittings 2a and 2b have at least substantially the same length. In one design, the flat tube fittings 2a and 2b are made of different materials, wherein each flat tube fitting 2a and 2b can be optimized for the temperature range of its respective flat tube heat exchanger. The flat tube fittings are welded together along weld seam 4.

[0044] In the illustrated embodiment, corrugated strips 3 are provided in the flat tubes 2a and 2b respectively, wherein the corrugated strips 3 have the same waveform and are arranged aligned with each other. In another design, the corrugated strips 3 arranged in the flat tubes 2a and 2b differ in waveform or wave number. In yet another design, the corrugated strips 3 extend from the two flat tubes 2a and 2b.

[0045] Figures 4 to 6 In longitudinal section, top view, or along according to Figure 4 The cross section of the section line VI-VI shows Figures 4 to 6 Flat tube heat exchanger 1 not shown in the image (see also...) Figures 7 to 10The tubular space 50 of the enclosed shell 5 is shown only in sections.

[0046] The tube bundle space 50 shown is cubic in shape. Within the tube bundle space 50 are arranged [a number of tubes arranged according to...]. Figure 1 A bundle of multiple flat tubes 2, wherein, in the illustrated embodiment, the flat tubes 2 are arranged in a rectangular configuration. The bundle comprises fifty flat tubes 2 arranged in ten rows, each row comprising five flat tubes 2 arranged side-by-side, their flat sides 200 lying in a common plane. Here, the number of rows and the number of flat tubes 2 in each row are exemplary; more or fewer rows may be used in other designs.

[0047] The ends 21 and 22 of the flat tube 2 are fixed in the bottom 52 of the tube.

[0048] In the flat tube 2, more precisely in the middle section 20 of the flat tube (see...) Figure 1 The flat tube 2 is provided with corrugated strips 3 as described above. Furthermore, corrugated strips 6 are also provided between the rows of flat tubes 2, with the crests 60 and troughs of these strips abutting the flat side 200 of the flat tube 2 externally. In the illustrated embodiment, the corrugated strips 6 arranged between the flat tubes 2 also have a sinusoidal waveform. The height of these corrugated strips 6 at least approximately corresponds to the spacing between two rows of flat tubes 2. In the illustrated embodiment, the corrugated strips 6 extend over the entire length of each row. In another design, two or more corrugated strips are provided per row.

[0049] As in Figure 6 The surface pressure is schematically applied to the housing 5 in the region of the tube bundle space 50, as indicated by the arrows. This surface pressure is higher than the pressure of the medium guided in or around the flat tube 2, particularly by about 1 to 4 bar. The surface pressure ensures that contact between the corrugated strips 3, 6 and the flat tube 2 is maintained on both the inner and outer sides during operation, without requiring material-locking connections, especially fusion welds or brazing connections, between the flat tube 2 and the corrugated strips 3, 6. The surface pressure can be applied using suitable equipment.

[0050] Figure 7 and Figure 8 By longitudinal section or along according to Figure 7 The cross section along section line VIII-VIII shows a first embodiment of a flat tube heat exchanger 1 with multiple flat tubes 2, wherein the shell 5 is surrounded by an outer shell 7 designed as a pressure vessel.

[0051] The housing 5 has a tube bundle space 50, an inlet-side collection space 54, an outlet-side collection space 56, and two tube bundle space interfaces 58. The tube bundle space 50 is separated from the collection spaces 54 and 56 by means of a tube bottom 52. The tube bottom 52 has an interface for the schematically shown flat tube 2, allowing the medium supplied to the inlet-side collection space 54 to flow at pressure p1 from the inlet-side collection space 54 into the flat tube 2 and from the flat tube 2 into the outlet-side collection space 56.

[0052] The flat tube heat exchanger 1 shown is preferably operated in a counter-current manner, wherein the medium guided around the flat tube 2 is input at pressure p2 via the tube bundle space interface 58 shown above in the drawing plane, and flows from there into the tube bundle space 50.

[0053] The outer shell 7, designed as a pressure vessel, surrounds the housing 5 at a certain distance while retaining a pressure space 70. For example... Figure 8 As schematically shown, the outer casing 7 has an interface 72 for media input and / or media output, thereby enabling the adjustment of the pressure p within the outer casing 7 by means of media input and / or media output. Here, the pressure p in the pressure space 70 of the outer casing 7, designed as a pressure vessel, is chosen such that this pressure is higher than the pressure p1, p2 of the medium guided in or around the flat tube 2, particularly by approximately 1 bar to approximately 4 bar. Thus, the casing 5 is externally loaded with surface pressure, which ensures... Figure 7 and Figure 8 The wavy bands 3 and 6, not shown in the image (see also...) Figures 1 to 6 It abuts against the flat tube 2 even without a material locking connection.

[0054] Figure 7 and Figure 8 The rectangular arrangement of the flat tube 2 shown is merely exemplary. Different arrangements of the flat tube 2 are possible in other designs, particularly annular arrangements as described in EP 2 584 201 A1. Reference is made in full to the disclosure of EP 2 584 201 A1.

[0055] Figure 9 and Figure 10 By longitudinal section or along according to Figure 9 The cross-section of the cutting line XX shows a second design of the flat tube heat exchanger 1 with multiple flat tubes 2. Figure 9 and Figure 10The flat tube heat exchanger 1 shown is a component of a schematically illustrated device for thermal afterburning (TNV), in which contaminated air or exhaust gas is introduced into the flat tube 2 via a collection space 54 on the inlet side and from there reaches the schematically illustrated combustion chamber 9. The combusted exhaust gas flows from the combustion chamber 9 into the tube bundle space 50 and is discharged into the surrounding environment via the tube bundle space interface 58. Here, the exhaust gas and the combusted exhaust gas typically flow in and around the flat tube 2 only under moderate overpressure.

[0056] In the flat tube 2, and additionally around the flat tube 2 according to the design scheme, there are also arranged... Figure 9 and Figure 10 The wavy bands 3 and 6, not shown in the image (see also...) Figures 1 to 6 In this embodiment, a device is provided for applying surface pressure to the housing 5 in order to ensure contact between the flat tube and the corrugated strips 3 and 6.

[0057] for Figure 9 and Figure 10 In the illustrated embodiment, for this purpose, the shell 5 of the flat tube heat exchanger 1 is also surrounded by an outer casing 7. Furthermore, multiple beam pairs 8 are provided, four in the illustrated embodiment. Each beam pair 8 comprises two beams 80 connected by means of a tie rod 82. In one design, a spring element is provided at the tie rod 82, by means of which the beams 80 are clamped together with a defined force. In another design, as an alternative or additional solution for this purpose, an adjustment element, particularly an adjusting thread, that can be adjusted manually or by a motor is provided. The outer casing 7 is subjected to surface pressure by means of the beam pairs 8. This load is transferred to the shell 5. In the illustrated embodiment, for this purpose, a pressure strut 84 is arranged between the outer casing 7 and the shell 5, the pressure strut being designed to uniformly load the shell 5 with surface pressure.

[0058] In the illustrated embodiment, the flat tubes 2 are arranged in a rectangular configuration. Therefore, a force applied in a direction perpendicular to the row direction of the flat tubes 2 is sufficient to ensure contact between the flat tubes 2 and the corrugated strips 3 arranged within them, as well as contact between the flat tubes 2 and the corrugated strips 6 arranged between the rows. Conversely, in a flat tube heat exchanger with an annular arrangement, a device is provided by which a force acting in the radial direction along the annular arrangement can be applied.

[0059] In the illustrated embodiment, a heat insulation portion 88 is provided between the housing 5 and the outer housing 7.

[0060] In an alternative design, the outer casing 7 is omitted, and surface pressure is applied directly to the casing 5 by means of beams 8.

[0061] according to Figures 1 to 6 In the embodiment shown, two corrugated strips 3 are arranged in the flat tube 2, each having a crest 30 and a trough aligned with each other.

[0062] Figure 11 The alternative arrangement of the corrugated belt 3 is shown in perspective. According to... Figure 11 In the arrangement structure, viewed along the longitudinal direction L, multiple corrugated bands 3, each having a crest 30 and a trough 31 extending along the longitudinal direction L, are arranged alternately in opposite directions. In other words, the crests 30 and troughs 31 of the corrugated bands 3 that follow each other are phase-shifted by 180°. Furthermore, transverse ribs 34 are arranged between the corrugated bands 3 that follow each other.

[0063] Figure 12 The cross-section shows the product according to Figure 11 The flat tube 2 has a corrugated strip 3 arrangement structure.

[0064] By following Figure 11 and Figure 12 The alternating reverse arrangement of the corrugated bands 3 creates vortices in the flow for improved heat transfer.

[0065] According to the present invention, by arranging the corrugated strip 3 inside the flat tube 2 and additionally on the outside of the flat tube 2, the heat transfer area for heat transfer is increased, thereby improving the efficiency of the flat tube heat exchanger 1. Here, the fusion welding and / or brazing connection between the corrugated strips 3, 6 and the flat tube 2 can be eliminated, in order to ensure contact between the corrugated strips 3, 6 and the flat tube 2 during operation by applying surface pressure to the shell 5 of the flat tube heat exchanger 1.

Claims

1. A flat-tube heat exchanger comprising a closed shell (5) having a tube bundle space (50) and a tube bundle arranged in the tube bundle space (50) of the shell (5), the tube bundle comprising a plurality of flat tubes (2), characterized in that, A corrugated strip (3, 6) is arranged in the flat tube (2) and in the tube bundle space (50) between the flat tubes (2), the corrugated strip having crests (30, 60) and troughs (31, 61) extending in the longitudinal direction of the flat tube (2), wherein the crests (30, 60) and troughs (31, 61) abut against the flat side (200) of the flat tube (2) inside or outside, and a device is provided that is adapted and set up for applying a surface pressure from the outside to the housing (5) at least in the region of the tube bundle space (50), the surface pressure being higher than the pressure (p1, p2) of the medium guided in or around the flat tube (2), thereby maintaining the contact between the crests (30, 60) and troughs (31, 61) of the corrugated strip (3, 6) and the flat tube (2) on the inside and outside during operation.

2. The flat tube heat exchanger according to claim 1, characterized in that, The housing (5) is loaded with surface pressure by means of the device, the surface pressure being 1 bar to 4 bar higher than the pressure (p1, p2) of the medium guided in or around the flat tube (2).

3. The flat tube heat exchanger according to claim 1 or 2, characterized in that, The corrugated bands (3, 6) have sinusoidal, triangular or sawtooth waveforms.

4. The flat tube heat exchanger according to claim 1 or 2, characterized in that, The width of the corrugated strip (3) arranged in the flat tube (2) is at least equal to the width of the flat side (200) of the flat tube (2).

5. The flat tube heat exchanger according to claim 1 or 2, characterized in that, The crests (30, 60) and troughs (31, 61) of the corrugated bands (3, 6) freely abut against the flat side (200) of the flat tube (2).

6. The flat tube heat exchanger according to claim 1 or 2, characterized in that, The device includes an outer housing (7) that receives the housing (5), wherein the outer housing (7) surrounds the housing (5) at a distance from it, at least in the region of the tube bundle space (50), while retaining the pressure space (70).

7. The flat tube heat exchanger according to claim 6, characterized in that, The outer casing (7) is designed as a pressure vessel with an interface (72) for media input and / or media output, wherein the pressure (p) in the pressure vessel can be regulated by means of media input and / or media output.

8. The flat tube heat exchanger according to claim 1 or 2, characterized in that, The device includes a beam pair and / or a plate pair (8) having two beams (80) or plates that are movable relative to each other, bend-resistant and connected by means of a tie rod (82), wherein at least one section of the housing (5) is arranged between the beams (80) or plates of the beam pair and / or plate pair (8).

9. The flat tube heat exchanger according to claim 8, characterized in that, The device includes an outer housing (7), wherein the outer housing (7) surrounds the housing at a distance from at least the region of the tube bundle space (50).

10. The flat tube heat exchanger according to claim 9, characterized in that, A pressure strut (84) for force transmission is arranged between the outer housing (7) and the housing (5).

11. The flat tube heat exchanger according to claim 9, characterized in that, A heat insulation part (88) is provided between the outer casing (7) and the casing (5).

12. The flat tube heat exchanger according to claim 1 or 2, characterized in that, The flat tube heat exchanger (1) is constructed in a rectangular arrangement, which has a square tube bundle space (50) and multiple flat tubes (2) arranged in rows and columns.

13. The flat tube heat exchanger according to claim 1 or 2, characterized in that, The corrugated strips (3, 6) are at least partially coated with a material that acts as a catalyst.

14. The flat tube heat exchanger according to claim 1 or 2, characterized in that, In the flat tube (2), at least two corrugated strips (3) are arranged in opposite directions when viewed in the longitudinal direction.

15. The flat tube heat exchanger according to claim 14, characterized in that, Transverse ribs (34) are arranged between two adjacent corrugated strips (3).

16. The flat tube heat exchanger according to claim 1 or 2, characterized in that, The flat tube (2) is composed of at least two flat tubes (2a, 2b) extending in the longitudinal direction (L).

17. The flat tube heat exchanger according to claim 1, characterized in that, The flat tube heat exchanger is designed for gaseous media.

Images