EP1234153A1

EP1234153A1 - Heat exchanger

Info

Publication number: EP1234153A1
Application number: EP00977332A
Authority: EP
Inventors: Jean Paul Hubert Janssens
Original assignee: Scambia Industrial Developments AG
Current assignee: Scambia Industrial Developments AG
Priority date: 1999-12-02
Filing date: 2000-12-01
Publication date: 2002-08-28
Also published as: AU2807801A; WO2001040730A1

Abstract

The invention relates to a heat exchanger that is provided with an axis and at least one body (5) which encompasses the axis and is ring-shaped in the cross-section thereof. Said body comprises involute sheet metal elements (23, 27) that are arranged around said axis in a successive manner. Edge strips (24, 25, 28, 29) that are welded to the sheet metal elements are alternately arranged between said sheet metal elements in the proximity to the involute side edges (23c, 23d, 27c, 27d) thereof or the inner and outer edges (23a, 23b, 27a, 27b) thereof. The sheet metal elements alternately define through-passages (33, 34) for a first and a second fluid (15, 16). Each through-passage (33, 34) contains an intermediate layer (31, 32) that consists of a wire hosiery. The edge strips (24, 25, 28, 29) and the wire hosiery keep the successive sheet metal elements (23, 27) stable and permanently at a distance from each other and are only provided with little heat conduction in the direction of flow.

Description

heat exchangers

Technical field

The invention relates to a heat exchanger with at least one heat exchange body with successive sheet metal elements which, together with gas-permeable intermediate layers arranged between them, alternately limit passages for a first fluid and a second fluid.

The heat exchanger is in particular provided to transfer heat between two gaseous fluids. For example, the heat exchanger can be used to heat hot exhaust gas from a hot gas engine, such as one

Stirlmgmotors or a gas turbine to recover and transfer to originally cold air, which is heated by the heat transfer and then fed to a burner.

State of the art

A heat exchanger known from GB 892 962 A has a heat exchange body with sheet metal elements which is annular in cross section. These have a central section in the form of an Archimedean spiral and with wavy ribs running along it, which obviously abut an adjacent sheet metal element and keep the ribless regions of the central sections at a distance from one another, so that they delimit spiral passages. The inner and outer edge sections of the sheet metal elements are angled or bent several times so that they abut each other in the innermost or outermost sections and limit axial channels. The sheet metal elements are connected to one another by welding or soldering. On the two The ends of the armetau sch body are attached to rings that alternate between the axial channels that follow one another along the circumference or connect them to an adjacent space through a hole. When the heat exchanger is in operation, hot exhaust gas is conducted from the inside to the outside and cold air from the outside to the inside through the heat exchange body.

The exhaust gases flowing from a Stirling engine or a gas turbine have high temperatures in modern engines or gas turbines, which are often 500 ° C. to approximately 1000 ° C. or a little more. If such exhaust gas is supplied to a heat exchange body, its sheet metal elements are subjected to severe temperature changes at the beginning and at the end of the operation of the heat exchange. Furthermore, strong temperature gradients result in a flow through the heat exchange body during operation along the flow paths of the fluids. Such temperature changes cause changes in the dimensions, which differ due to the temperature gradients.

Sheet metal elements provided with ribs and angled or bent at the inner edges and outer edges according to GB 892 962 A can be deformed strongly and permanently by the dimensional changes occurring at high exhaust gas temperatures and the associated stresses. The deformations are further increased in that the bent and abutting edge sections of the sheet metal elements connect all sheet metal elements to one another in a relatively stiff and unyielding manner. The deformations generated in turn have the result that the passages are expanded in places and narrowed in places or are even more or less completely closed, as a result of which the properties of the heat exchanger are greatly deteriorated. In addition, GB 892 962 A does not show whether and how the spiral Passages are completed at the two ends of the heat exchange body and whether and how there and in the axial channels of the heat exchange body, mixing of the hot exhaust gas with the air can be prevented. Because of the complicated shapes of the sheet metal elements, because the rings mentioned must have a hole aligned with them for every second axial channel and because the inner ends of the spiral central sections of the sheet metal elements in a cut perpendicular to the axis form a rather acute angle with the inner surface of the heat exchange element. Form the body, the latter can also have only a relatively small number of passages distributed around its inner circumferential surface for a given, given inner diameter. Furthermore, the production of the bent edge sections is complicated and expensive.

US 4 506 502 A discloses a heat exchanger with an annular heat exchange body with spiral passages. The heat exchange body is made of ceramic or steel, but the internal structure and the manufacture of the heat exchange body are not disclosed in more detail. In addition, the hot exhaust gas is passed through the heat exchange body from the outside to the inside during operation. The heat exchange body is therefore very hot on its outer surface, so that a lot of heat is released to the environment and high heat losses occur.

A heat exchanger known from US 3741 293 A has an annular heat exchange body with flat, radial sheet metal elements and arranged in rows between them

Secondary surface elements, which are formed by shuttering. Since the passages run radially, they become wider towards the outside and have only a short length. In addition, the distance between the adjacent sheet metal elements is relatively large. This heat exchange body therefore results - based on a certain volume - only a low heat exchange performance. Incidentally, this heat exchanger still has disadvantages that are in part similar to those of the heat exchanger according to GB 892 962 A, cited first.

A heat exchanger known from US Pat. No. 5,060,721 A has an annular heat exchange body with sheet metal elements which are generally bent in the form of an involute. Each of these forms an irregular hexagon in the developed, flat state and has a trapezoidal central section and a wing on both sides of this. The middle section has waves running along the involutes. The wings have some waves that form channels parallel to the axis of the heat exchange body. This heat exchanger has some disadvantages similar to that

Heat exchanger according to GB 892 962 A, the production and assembly of complicated sheet metal elements in particular being time-consuming and expensive.

GB 1 172 247 A discloses heat exchangers with an approximately cuboid heat exchange body. This has a stack of rectangular plates with a flat main section and edge sections bent upwards. An intermediate layer consisting of a wire mesh is arranged between the adjacent plates. In the variants shown in the various drawing figures, the wire grids consist of wires lying on one another and crossing one another at right angles. According to the figures, the latter form angles of approximately 45 ° with the rectangular sides of the plates. When using the

Heat exchangers generally flow through these flowing fluids more or less parallel to the longer rectangular sides. The wire grids therefore provide fairly good heat conduction along the flow paths of the fluids. As a result, a large part of the hotter fluid supplied heat is transported away from the heat exchanger and is not transferred. Far away, the edges of the plates are provided with rubber seals that are not suitable for high temperatures. These known heat exchangers were therefore not suitable for exhaust gases from internal combustion engines and gas turbines at temperatures of up to approximately 1000.degree.

Outline of the invention

The invention has for its object to provide a heat exchanger which makes it possible to avoid disadvantages of the known heat exchangers. In particular, the sheet metal elements should on the one hand be sufficiently stable and permanently connected to one another in such a way that the passages for the two fluids are and remain perfectly separated from one another. On the other hand, the sheet metal elements should maintain their shape as well as possible even when a fluid is supplied at a very high temperature and ensure that all passages are uniform

Allow fluid flow. Furthermore, the heat exchanger should be economical to manufacture and enable the heat losses to the environment to be kept low.

This object is achieved according to the invention by a heat exchanger with the features of claim 1, ie by a heat exchanger with at least one heat exchange body which is annular in cross section and which surrounds an axis and has successive sheet metal elements around it, which together alternate first passages for define a first fluid and second passageways for a second fluid, each sheet metal element having an inner edge, an outer edge and two side edges running from the inner edge to the outer edge, adjacent sheet metal elements being substantially constant along their side edges Have distances from each other and wherein the heat exchanger is characterized in that each sheet metal element forms a quadrilateral, which are arranged between the sheet metal elements delimiting a first passage along their side edges along these metallic edge strips and are firmly and tightly connected to the sheet metal elements concerned and in that are arranged between the sheet metal elements, which together delimit a second passage, at their inner edges and at their outer edges, along these metallic edge strips and are firmly and tightly connected to the sheet metal elements in question.

The invention further relates to a heat exchanger with at least one heat exchange body with successive sheet metal elements which alternately delimit passages for a first fluid and a second fluid and between which gas-permeable intermediate layers are arranged, each sheet metal element having two side edges facing away from one another and the heat exchanger being characterized thereby , that the

Side edges of the sheet metal elements belonging to the same heat exchange body and / or edge strips arranged at these side edges together define two end faces of the heat exchange body, that at each end face there is at least one metallic foil on the side edges of the sheet metal elements and that heat-insulating insulation on that facing away from the sheet metal elements Side of each slide is arranged.

The invention further relates to a heat exchanger with at least one heat exchange body which is annular in cross section and which surrounds an axis and has successive sheet metal elements around it, which together alternately delimit first passages for a first fluid and second passages for a second fluid, each of which Sheet metal element an inner edge, an outer edge and two from Has inner edges to the outer edge extending side edges, adjacent sheet metal elements along their side edges have substantially constant distances from one another, the passages being between openings near the inner edges and openings near the

Extend outer edge and wherein the heat exchanger is characterized in that the sheet metal elements have a dimension measured along their side edges, which is at least twice a dimension of the sheet metal elements measured along the axis.

The invention also relates to a heat exchanger with at least one heat exchange body with successive sheet metal elements which alternately delimit passages for a first fluid and a second fluid and between which gas-permeable intermediate layers are arranged, each sheet metal element having two mutually facing, parallel side edges and at least essential parts of the passages run along the side edges and wherein the heat exchanger is characterized in that each

Intermediate layer consists of a wire knitted fabric which has rows of stitches with adjacent stitches formed from contiguous wire sections and that these rows of stitches are generally approximately at right angles to the side edges of the sheet metal elements.

Advantageous refinements of the heat exchanger emerge from the dependent claims.

Brief description of the drawings

The subject matter of the invention is subsequently explained in more detail with reference to exemplary embodiments shown in the drawings. Show in the drawings 1 is a simplified, schematic oblique view of a heat exchanger,

2 shows a simplified, schematic axial section through the heat exchanger and its heat exchange body,

3 shows a schematic cross section through the annular heat exchange body of the heat exchanger,

4 shows a schematic section along the line IV-IV of FIG. 3 through a first involute-shaped fluid passage of the heat exchange body,

5 shows a section along the line V-V of FIG. 3 through a second fluid passage of the heat exchange body,

FIGS. 6, 7 are views of edge sections of the unwound second sheet metal element shown in FIG. 5 in the viewing directions designated by arrows V and VI in FIG. 5 on a larger scale,

8 is a view of the developed, first sheet metal element shown in FIG. 4 on a larger scale,

9 shows a detail from FIG. 8 on an even larger scale,

10 is a view of the first sheet metal element shown in FIGS. 4, 8 and 9 in the viewing direction designated X in these figures on the same scale as FIG. 9,

11 shows a simplified cross section through a region of the end section of the heat exchange body located at the top in FIG. 2 on a larger scale than FIG. 2, 12 shows a schematic, simplified oblique view of a region of the heat exchange body with a view of the inner edge of the end surface located at the top in FIG. 2,

13 is a simplified oblique view of another, broken heat exchanger with only one heat exchange body,

14 shows a simplified top view of the upper end of the heat exchange body shown in FIGS. 12 and 13 and the foils resting thereon,

15 shows a section along the arc XV - XV of FIG. 14 through the heat exchange body and the foils resting thereon,

16 shows an axial section through a region of the heat exchanger according to FIG. 13 on a larger scale,

17 shows a simplified, schematic axial section through a heat exchanger with two heat exchange bodies,

FIGS. 18, 19 are similar sections to FIGS. 4, 5 through the heat exchange body according to FIG. 17 along first and second, involute-shaped passages,

Fig. 20 is a schematic axial section through a heat exchanger with six heat exchange bodies and

Fig. 21 is a schematic axial section through a heat exchanger with four heat exchange bodies.

Regarding FIGS. 4, 5, 12, 13, it should also be noted that the cuts shown in these along a involute passage, so that the sheet metal elements appear in a developed, flat state. The parts of the housing adjoining the heat exchange body and the fluid guiding means are, however, for simplification, drawn as in a section running radially to the axis. Incidentally, it should also be noted with respect to FIG. 12 that, for the sake of simplicity, no knitted wire fabrics were drawn in this. Furthermore, they were distributed around an arcuate section of the cylindrical, inner surface of the heat exchange body

Sheet metal elements shown as if their inner edges were in one plane.

Description of the preferred embodiments

The heat exchanger 1 shown in FIGS. 1 and 2 has an axis 2. The heat exchanger 1 has a housing 3, which is shown only partially and schematically. This contains a heat exchange body 5, which is described in more detail below. The heat exchanger 1 and in particular its heat exchange body 5 are essentially rotationally symmetrical to the axis 2. The heat exchanger 1 has fluid guide means 7 which are partially formed by housing parts and which, like the housing, are only partially and schematically illustrated. The housing 3 and / or the fluid guide means 7 have a first fluid

Input 8, a first fluid outlet 9, a second fluid inlet 10 and a second fluid outlet 11.

Furthermore, two gaseous, flowing fluids, namely a first fluid 15 and a second fluid 16, are indicated by arrows in FIGS. 1, 2. The arrows representing the first fluid 15 are drawn with full lines and the arrows representing the second fluid 16 are shown in dashed lines. The heat exchanger 1 can, for example, belong to a device which still has a hot gas engine (not shown) or Stirlmg engine or possibly a gas turbine. The engine or the turbine can then feed the first fluid inlet 8 hot exhaust gas, which forms the first fluid 15 and, after passing through the heat exchange body 5 from the first fluid outlet 9, for example via an additional one, for generating hot water serving heat exchanger and / or via a filter and / or any other device in the environment. The second fluid 16 consists, for example, of air which is sucked in from the surroundings by a suction device and possibly compressed and fed to the second fluid inlet 10. After passing through the heat exchange body, the air is fed from the second fluid outlet 11, for example to a burner for operating the hot gas engine or the gas turbine.

The heat exchange body 5 and parts thereof can be seen particularly clearly in FIGS. 3 to 12. The heat exchange body 5 is annular in cross section and forms a ring and / or a sleeve. The heat exchange body 5 has an inner lateral surface 5a, an outer lateral surface 5b and two end surfaces 5c and 5d facing away from each other. The two lateral surfaces 5a, 5b are parallel to the axis 2 and essentially cylindrical and circular in cross section. The two end faces 5c, 5d form an angle with the axis 2, namely a right angle, and are flat and parallel to one another. The heat exchange body 5 has, around the axis 2, alternating successive first fluid guide elements 21 and second fluid guide elements 22. One of the first fluid guide elements 21 can be seen partially separately in FIGS. 8, 9, 10. Each first fluid guide element 21 has a first sheet metal element 23 and two first edge strips 24, 25. Sections of a second fluid guide element 22 can also be seen in FIGS. 6 and 7. Every second fluid guide element 22 has a second sheet metal element 27 and two second edge strips 28, 29. Gas-permeable, first and second intermediate layers 31 and 32 are arranged between the successive sheet metal elements 23, 27. The successive sheet metal elements, together with the gas-permeable intermediate layers 31, 32 arranged between them, delimit first and second fluid passages 33, 34 for the first fluid 15 and second fluid 16, respectively.

The first and second sheet metal elements 23, 27 are of identical design and have both identical shapes and identical dimensions. The sheet metal elements 23, 27 have four mutually opposing edges, are quadrangular in the flat, developed state and form a right-angled parallelogram, namely a rectangle. The sheet metal elements 23, 27 are parallel to the axis 2 and extend in an involute shape from the axis 2 to the outside in a cross section perpendicular to this. The two shorter edges of each sheet metal element 23, 27 are straight, parallel to one another and to the axis and are referred to below as the inner edge 23a, 27a and outer edge 23b, 27b, the inner edges 23a, 27a at the ends near the axis and the outer edges 23b, 27b are located at the ends of the sheet metal elements further away from the axis. The two longer edges of each sheet metal element 23, 27 are curved and parallel to one another and are referred to below as side edges 23c, 23d and 27c, 27d. The sheet metal elements 23, 27 have a dimension measured along the curved side edges 23c, 23d, 27c, 27d, ie a length which is at least 2 times, preferably at least 2.5 times and for example at least or approximately 3 times that dimension parallel to axis 2, ie width, of the sheet metal elements. The edge strips 24, 25, 28, 29 consist of a metallic material, namely sheet metal strips. The first edge strips 24, 25 belonging to one of the first fluid guide elements 21 are located at the two side edges 23c, 23d of the first sheet metal element 23 of the relevant fluid guide element and run along these curved side edges. The second edge strips 28, 29 belonging to one of the second fluid guide elements 22 are at the inner edge 27a or outer edge 27b of the second

Sheet metal element 27 of the relevant fluid guide element is arranged and extend along these straight edges 27a, 27b parallel to axis 2. The various edge strips 24, 25, 28, 29 are rectangular in cross-section and lie on the sheet metal elements with their wider longitudinal surfaces. One of the narrower longitudinal surfaces of the edge strips is at least approximately flush with the sheet metal element edges along which they run. The various edge strips 24, 25, 28, 29 extend at least approximately along the entire edges of the sheet metal element in which they are arranged. The edge strips 24, 25 running along the curved side edges extend, for example, along the entire length of the side edges from the inner edge to the outer edge of the sheet metal elements. In contrast, the edge strips 28, 29 running along the straight edges 23a, 23b, 27a, 27b can, for example, be slightly shorter than these edges. The ends of the edge strips 28, 29 are then - as shown for the upper end of inner edge strips 28 in Fig. 12 - a little, for example about 2 to 4 mm, from the side edges of the

Sheet metal elements 23 and 27 offset. The ends of the first and second edge strips should, however, preferably still partially overlap at the corners of the sheet metal elements in a projection parallel to the axis 2 and to the lateral surfaces 5a, 5b.

As will be explained in more detail, the passages 33, 34 and the fluid flows therein run at least generally in the longitudinal directions of the sheet metal elements 23, 27 and thus parallel to their side edges 23c, 23d, 27c, 27d. The side edges of the sheet metal elements and / or the edge strips 24, 25 running along the side edges therefore also form the side edges of the passages 33, 34. The sheet metal elements 23, 27, which are edge strips 24, 25 and the passages 33, 34 running along their side edges in a section perpendicular to axis 2 essentially and at least approximately involute. However, their shapes may possibly be flattened in the inner and / or outer edge regions in which the edge strips 28, 29 are arranged and may differ slightly from the ideal involute shape. Apart from this, each sheet metal element is free of angled and / or bent edge sections and also free of elevations and / or depressions, such as waves and / or ribs and the like. Each sheet metal element is therefore completely straight and smooth everywhere in the axial direction and essentially in cross-sections perpendicular to the axis 2 - that is to say apart from the aforementioned small deviations in the inner edge and outer edge - at least approximately involute-shaped and smooth. Accordingly, each sheet metal element is curved continuously and smoothly everywhere, in a section perpendicular to axis 2, and in fact everywhere on the same side, so that the curvature has the same sign at all points of the sheet metal element.

The edge sections of the sheet metal elements 23, 27 which form the inner edges 23a, 27a of the sheet metal elements are preferably more or less perpendicular to the cylindrical inner jacket surface 5a of the heat exchange body 5 which forms a circle in cross section, perpendicular to the axis 2. The sheet metal elements or the tangents adhering to these can then form an angle with the inner lateral surface 5a which is 65 ° to 115 °, preferably 80 ° to 100 ° and, for example, approximately 85 ° to 95 °. Accordingly, the mentioned tangents run at least approximately radial to the axis 2. This ensures that the first fluid can flow through the first passages during operation and that the number of sheet metal elements and passages distributed around the inner lateral surface 5a and at a specific, predetermined diameter of the inner lateral surface 5a and certain ones The spacing of the adjacent sheet metal elements from each other and at certain thicknesses of the sheet metal elements has at least approximately the greatest possible value. Since the sheet metal elements are involute, the adjacent sheet metal elements have the same distance from one another from the inside to the outside. Otherwise, the dimension or length of a sheet metal element measured along an involute is of course greater than the difference between the radii of the two lateral surfaces 5b and 5a.

Each intermediate layer 31, 32 consists of, for example, an approximately square-shaped wire mesh, namely a wire knitted fabric, which can be seen particularly clearly in FIG. 9 and is labeled mt 37 there. The wire knitted fabric 37 has a number of courses 37a with loops 37b. The adjacent stitches 37b belonging to the same stitch row 37a are formed by contiguous wire sections. The wire sections belonging to successive stitch rows 29a cross each other at intersection points 37c and form a kind of knot there. Each row of stitches 37a is generally transverse and perpendicular to the side edges 23c, 23d, 27c, 27d of the sheet metal elements 23, 27 and thus also generally transverse and perpendicular to the longitudinal directions and side edges of the passages 33, 34. Each row of stitches, ie the straight line defined by mutually corresponding positions of the stitches of this stitch row — for example the apex of these stitches — can form an angle with the side edges 23c, 23d, 27c, 27d of the sheet metal elements 23, 27, which is preferably 70 ° to 90 ° and better 80 ° to 100 ° or even 85 ° to 95 ° and as precisely as possible 90 °. The adjacent rows 37a of mesh are interlocked.

The wire mesh or wire knitted fabric 37 is produced by knitting from a single connected wire. For example, when knitting, a tube is first formed. This is then cut open in its longitudinal direction and cut into roughly flat pieces with the desired sizes. Originally, all the rows of stitches 37a also consist of a coherent one

Wire. If a knitted wire is arranged between two sheet metal elements, each pair of successive rows 37 of stitches is at most connected at one end or nowhere over a continuous wire section.

The width of each first intermediate layer 31 is approximately equal to the width of the first passage 33 present between the edge strips 24, 25. Each first intermediate layer also extends at least approximately from the inner edge 23a to the outer edge 23b of the associated first sheet metal element 23 and thus essentially over the whole Long of the first passage 33. The width of each second intermediate layer 32 is approximately equal to the entire width of the sheet metal elements 23, 27. Each second intermediate layer 32 furthermore approximates the edge strip 28 arranged at the inner edge 27a of the associated sheet metal element 27 and extends in the longitudinal direction of the sheet metal element 27 and of the second fluid passage 34 over most of the length of the fluid passage 34, but not entirely to the edge strip 29, so that there is a strip-shaped area of the second passage 34 which runs parallel to the axis and to the outer edge 27c remains.

The sheet metal elements 23, 27, the edge strips 24, 25, 28, 29 and the wire mesh 37 consist, for example, of stainless steel containing chrome. The sheet metal elements have a thickness which - depending on the other dimensions of the sheet metal elements - is at most 5 mm, expediently at most 1 mm, preferably at most 0.5 mm, normally even better at most 0.3 mm and for example approximately 0.2 mm. The thickness of the wires forming the knitted wire is, for example, the same for all intermediate layers, but could possibly be different for the first and second intermediate layers and, depending on the size of the sheet metal elements, is also at most 5 mm, expediently at most 1 mm, preferably at most 0 , 8 mm and, for example, about 0.3 mm to about 0.7 mm. The open area of the knitted wire 37 is preferably at least 50% and, for example, approximately 60% to 90% of the total area occupied by the knitted wire.

The wires of the knitted wire 37 are preferably circular in cross section. Each edge strip 24, 25, 28, 29 has a thickness which is approximately equal to twice the diameter of the wires and / or possibly a little larger than this

Diameter is. Two mutually adjacent sheet metal elements 23, 27 rest on the two mutually facing surfaces of the edge strips 24, 25 or 28, 29 located between them. Furthermore, the two sheet-metal elements each abut one of the intersecting wire sections at the crossing points 37c of the wire grid 37 located between them. The edge strips 24, 25, 28, 29 and the intermediate layers 31, 32, each consisting of a knitted wire, thus serve as spacing means and hold the mutually adjacent sheet metal elements at the desired distance from one another. In the areas of an intermediate space between two sheet metal elements which are not occupied by intersections 37c, this intermediate space is free. The intermediate layers 31, 32 arranged in the spaces between the sheet metal elements are - as already written - permeable to gas, so that the spaces just form the fluid passageways 33, 34.

The mutually adjacent sheet metal elements 23, 27 are fixedly connected to them in the edge strips 24, 25 and 28, 29 arranged between them and thereby also in pairs. In the manufacture of the heat exchange body 5, for example, the first edge strips 24, 25 are fixed to the associated first sheet metal element 23 by some spot welding connections designated by 35 in FIGS. 8, 9 and the second edge strips 28, 29 are fixed by some spot welding connections fixed to the assigned, second sheet metal element. The first and second fluid guide elements 21 and 22 are formed. Furthermore, each of the intermediate layers 31, 32 consisting of a knitted wire is fastened at some points to the associated sheet metal element 23 or 27 by spot welding connections. Each wire knitted fabric is therefore at most attached to a single sheet metal element, so that the wire knitted fabrics support the sheet metal elements between which they are arranged, but do not rigidly connect them to one another. If the edge strips and wire meshes have been fixed in the manner described on the associated sheet metal element, the fluid guide elements 21, 22 and intermediate layers 31, 32 or wire meshes can be combined to form the heat exchange body and, for example, along the entire length of the between them arranged edge strips with these and possibly also directly welded to one another. The sheet metal elements are then almost inextricably paired along the edge strips and tightly connected.

When welding the sheet metal elements and edge strips, for example, a pair of sheet metal elements 23, 27 can first be arranged on one another in such a way that the inner edges 23a, 27a and the outer edges 23b, 27b and along these marginal strips 28, 29 are flush. The adjacent sheet metal elements and edge strips can then first be connected along their inner edges 23a, 27a and outer edges 23b, 27b by welded connections 38 or welded seams shown in FIGS. 11 and 12 and 33 with the straight edge strips 28, 29 and with one another. If several or all of the sheet metal elements used to form the heat exchange body are welded in pairs in this way, these can be assembled from a pair of sheet metal element sub-units to form a heat exchange body and successively along the involute-shaped side edges 23c, 23d, 27c, 27d with the are welded along these extending edge strips 24 and 25 and via these. Welded connections or weld seams are formed, one of which is shown in FIG. 12 and is designated by 39. The sheet metal elements can then possibly also be connected at the ends or end faces of the curved edge strips 24, 25 by welded connections 39a to these edge strips and to one another. The along the perimeter of the

Heat-exchange body successive sheet metal elements are then alternately firmly connected to one another at their inner and outer edges or along their side edges along the edge strips arranged between the relevant edges. In this case, weld connections can be formed at the four corners of the sheet metal elements, which run uninterruptedly around the axis 2 along the circumference of the inner edges and outer edges of the end faces 5c, 5d. In contrast, the sheet metal elements 23, 27 delimiting a first passage 33 in pairs are in theirs

Inner edges 23a, 27a and in their outer edges 23b, 27b between the edge strips 24, 25 running along their side edges free of rigid connections between them. The sheet metal elements 23, 27 delimiting a second passage 34 in pairs are shown in an analogous manner their side edges 23c, 23d, 27c, 27d between the edge strips 28, 29 arranged at their inner edges 23a, 27a and outer edges 23b, 27b and running along them free of rigid connections between the sheet metal elements.

The heat exchange body 5 can also be provided with at least one retaining ring 40 enclosing its outer jacket surface and preferably with two or more such, wherein in FIG. 2 two retaining rings 40 spaced apart from one another in the axial direction are shown as an example. Each retaining ring has, for example, a metallic band made of stainless steel and possibly a tensioning device for tensioning the band, so that in the assembled state it bears firmly against the outer edges of the sheet metal elements and / or edge strips which define the outer jacket surface 5b of the heat exchange body. The retaining rings can also be secured against axial displacements by means of additional holding means, but should not be welded to the sheet metal elements or in any case not with immediately successive sheet metal elements or otherwise rigidly connected.

The housing 3 has two annular holding members 41 and 42 to hold the heat exchange body 5 at its end faces 5c, 5d. Each holding member 41, 42 has an annular, in axial section angular metal wall 43 or 44 with two conical parts or legs inclined inwards or outwards from their apex. On the edges facing away from the apex, a metallic foil 45 or 46 is held, which abuts the end face 5c or 5d of the body 5. At least some of the said edges of the walls 43, 44 can also be welded tightly to the locations of the sheet metal element edges and edge strips located at them. For example, the inner edge of the the lower wall 43 and the outer edge of the upper wall 44 at the inner edge of the lower end face 5c or at the outer edge of the upper end face 5d of the heat exchange body may be welded thereto. In contrast, the outer edge of the lower wall 43 and the inner edge of the upper wall 44 are not welded to the heat exchange body, for example. The cavity delimited by the angular wall 43, 44 and the film 45 or 46 contains a heat-insulating, elastically deformable insulation 47 or 48. This is heat-resistant up to very high temperatures, for example at least approximately 1000 ° C. Each insulation 48 can consist, for example, of a preformed, deformable body and contain, for example, a fiber material and a binder. However, the insulation can also be made from a loosely connected cavity

Walls are made of full material. Each insulation 47, 48 rests on the side of the film 45 or 46 facing away from the heat exchange body and presses it against the end face 5c or 5d of the heat exchange body. The walls 43, 44 and foils 45, 46 are made, for example, of stainless steel containing chromium. For example, while the walls 43, 44 are approximately 1 mm to 2 mm thick, the thickness of the foils 45, 46 is at most 0.1 mm and, for example, 0.03 mm to 0.07 mm. The films are therefore quite easily deformable and can nestle well and the end faces 5c, 5d.

The foils 45, 46 cover the largest parts of the side edges of the sheet metal elements 23, 27 and fluid passages 33, 34 and close the largest parts of the second fluid passages 34, which are open towards the end faces 5c, 5d, at least approximately tightly at their side edges from.

Each first fluid passage 33 has a first fluid outlet opening 33a and a first fluid outlet opening 33b for the first fluid 15. Each second fluid passage 34 has a second fluid outlet opening 34a and a second fluid outlet. Outlet opening 34b for the second fluid. These openings 33a, 33b, 34a, 34b are all formed by slots between edge sections of adjacent sheet metal elements 23, 27 delimiting the passage in question. Each first inlet opening 33a is located between the

Inner edges 23a, 27a of two sheet metal elements 23, 27. Each first outlet opening 33b is located between the outer edges 23b, 27b of two sheet metal elements 23, 27. The openings 33a, 33b extend in the axial direction from an edge strip 24 to an edge strip 25 Every second inlet opening 34a is located between sections of the side edges 23c and 27c of two sheet metal elements 23, 27 in the vicinity of the outer edges 23b, 27b of these sheet metal elements. Every second inlet opening connects approximately to the outer jacket surface 5b and namely runs inward from an edge strip 29 to the holding member 41 and extends only over a portion of the side edges 23c, 27c which is very much shorter than the entire side edges. Every second outlet opening 34b is located between sections of the side edges 23d, 27d of two sheet metal elements 23, 27 in the vicinity of the inner edges of these sheet metal elements. Every second outlet opening 34b connects approximately to the inner jacket surface 5a and namely runs outward from an edge strip 28 to the holding member 42 and extends only along side edge sections which are much shorter than the entire side edges 23d, 27d.

The first inlet openings 33a of the various first passages together define a first inlet region 5e of the heat exchange body 5. The first outlet openings 33b analogously define a first outlet region 5f. Furthermore, the second inlet openings together and the second outlet openings together define a second inlet region 5g and a second outlet region 5h, respectively. Each of these areas is ring-shaped and lies in an axis 2 enclosing area. The first inlet area and the first outlet area are located on the inner jacket surface 5a and on the outer jacket surface 5b, respectively, and extend in the axial direction over most of the jacket surfaces. The second inlet area 5g and the second outlet area 5h are located at and / or m of one of the two opposite end faces 5c and 5d, but extend in the radial direction only over a small part of these. Although the first inlet area and the second outlet area are located at or near the inner edges, these two areas are spatially separated from one another. Likewise, the first outlet area and the second inlet area are spatially separated from one another. The inlet and outlet areas which are adjacent to one another in pairs are spaced apart from one another in the axial direction by the width of a first edge strip 25 or 24 and along the involute side edges of the sheet metal elements by the width of a second edge strip 28 or 29.

The inner lateral surface 5a of the heat exchange body 5 encloses a first, essentially cylindrical inlet chamber 51 which adjoins the first inlet region 5e of the heat exchange body. The housing 3 and / or the fluid guide means 7 further delimit a first outlet chamber 52, a second inlet chamber 53 and a second outlet chamber 54. The first inlet chamber 51 is, for example, at its end located at the bottom in FIG. 2 by a hollow closing element 57 completed, which has metallic walls 58 and contains heat insulating insulation 59. The three chambers 52, 53, 54 are ring-shaped and, for example, delimited by metallic walls and adjoin the first outlet area 5f, the second inlet area 5g and the second outlet area 5h of the heat exchange body 5. The fluid guide means 7 have a first fluid Entrance 8 with the first inlet chamber 51 connecting, conical inlet part 61, which widens to the first inlet chamber 61 hm and approximately at the annular edge between the surfaces 5a, 5d of the heat exchange body is tightly connected to it, namely welded. The fluid guide means also connect the first outlet chamber 52 to the first fluid outlet 9, the second fluid inlet 10 to the second inlet chamber 53 and the second outlet chamber 54 to the second fluid outlet 11, all of which connections are tight.

The first and second sheet metal elements are completely identical apart from the edge strips attached to them. As already written, the sheet metal elements are completely involute in axial sections from one side edge to the other side edge and are straight everywhere and in sections running transversely to axis 2 everywhere from the inner edge to the outer edge. So you have no bent or angled edge sections. This contributes to an inexpensive manufacture of the heat exchanger.

The openings 33a, 33b, 34a, 34b of the passages 33, 34 connect the passage in question between the aforementioned edges of the sheet metal elements with a space adjacent to these edges in the vicinity of the heat exchange body, namely with one of the chambers 51, 52, 53 , 54. The openings of the latter which serve to guide the fluids into the heat exchange body and to lead the fluids out of the heat exchange body are thus formed by structurally simple means. The inlet and outlet openings can in particular be formed without the heat exchange body having to be provided with additional channels for this purpose, as is the case with various known ones Heat exchangers is the case. This also contributes to the economical manufacture of the heat exchanger.

When using the heat exchanger 1, the first fluid 15 consisting of exhaust gas in the first inlet chamber 51 has an inlet temperature which is much higher than the inlet temperature of the second fluid 16 consisting of air in the second inlet chamber 53 first fluid 15 is distributed in the inlet chamber 51 to the first fluid inlet openings 33a, flows into the first fluid passages 33, through them outward from the axis 2 and then through the first fluid outlet openings 33b into the first outlet chamber 52. The first fluid flows in the heat exchange body 5 generally approximately transversely to the axis 2 along the involute-shaped first passages. The second fluid 16 initially flows from the second inlet chamber 53 approximately parallel to the axis 2 through the second fluid inlet openings 34a into the second fluid passages 34, is distributed in the wire-knit-free starting sections by these over the axial dimension of the second passages , then flows approximately perpendicular to axis 2 along the involute-shaped passages from the outside in to axis 2, is deflected again in an approximately axial direction near the inner ends of the passages, and then flows through the second fluid outlet openings 34b into the second Outlet chamber 54. Since the second inlet openings 34a and the second outlet openings 34b are located at the end faces 5c, 5d facing away from one another, the second fluid .16 follows approximately Z-shaped flow paths in the axial section shown in FIG. 5, but most of them Flow paths are approximately transverse to axis 2 along involutes.

If the two fluids 15, 16 flow in opposite directions for the most part through the When the heat exchange body flows, the exhaust gas, which was originally much cooler, gives off heat 15 to the initially fluid second fluid 16, which is initially cold. The first fluid is thus cooled from the inside to the outside on its flow paths, while the second fluid is heated from the outside to the inside. The temperature of the heat exchange body 5 thus decreases outwards from the axis, so that the heat exchange body, with its relatively large, outer jacket surface 5b, has only a low temperature, at most little deviating from the ambient temperature. Since the sheet metal elements 23, 24 are very thin, they dissipate little heat to the outside. The intermediate layers 31, 32 made of knitted wire 37 have only small material cross-sectional areas compared to the cross-sectional dimensions of the fluid passages 33, 34 and accordingly result in only a low heat conduction. Since the mesh rows 37a of the wire mesh 37 run transversely to the longitudinal direction of the passages, to the main flow directions of the fluids and to the temperature gradients in the heat exchange body, the heat conducted through the wire mesh must also pass through contact points of wire sections in order to Row 37a to get to the next. The wire grids therefore conduct very little heat away from the inside along the passageways. The metallic foils 45, 46 present at the end faces 5c, 5d of the heat exchange body are very thin and, accordingly, only result in low heat conduction. Furthermore, the foils are insulated in the axial direction by the insulations 47 and 48, respectively. For all these reasons, the heat exchanger releases only a little heat to the surroundings, so that a very large part of the heat of the hot exhaust gas or first fluid 15 can be recovered.

The temperature of the first fluid 15 consisting of exhaust gas can, for example, be introduced into the heat exchanger 500 ° C to about 1000 ° C or possibly more. The various parts of the heat exchange body 5 are therefore greatly stretched during operation in the inner region of the heat exchange body due to the temperature increase. The mutually adjacent sheet metal elements 23, 27 are stably supported against one another by the edge strips 24, 25, 28, 29 and by the wire sections of the wire knitted fabrics 37 resting against one another and at the sheet metal elements at the intersection points 37c, so that the widths of the passages even in the case of large ones Temperature changes are changed approximately the same for all runs. The wires of the knitted wires between the crossing points 37c can deform relatively freely, so that the temperature changes and temperature gradients do not cause excessive stresses and damage to the knitted wires and the sheet metal elements supported by them. The sheet metal elements following one another around the axis 2 are - as already described - connected to one another in each case with two edge strips 24, 25 or 28, 29 and at least largely unconnected with the other edges. Furthermore, the sheet metal elements in their main areas located between the edge strips are free of rigid connections. The described way of connecting the sheet metal elements to a heat exchange body contributes to the fact that the sheet metal elements also by large temperature changes and

Temperature gradients are not damaged. Furthermore, the design of the two holding members 41, 42 acting on the end faces of the heat exchange body enables the sheet metal elements to move little perpendicularly to the axis 2 em with respect to the holding members and that the latter can adapt to changes in the axial dimensions of the heat exchange body. As described, the length of the sheet metal elements and passages measured along the curved side edges is at least twice and, for example, at least or approximately 3 times that axially parallel width of the sheet metal elements and passages. This large ratio between length and width makes the heat exchange body easily deformable. For all these reasons, the heat exchanger 1 is very solid and durable.

In particular, numerous cold starts were carried out in tests in which abruptly hot exhaust gas with temperatures in the magnitude of approximately 700 ° C. was supplied to a cold heat exchanger. Although the heat exchanger is subjected to very heavy loads during such cold starts, no damage was found even after a large number of such cold starts.

The inside diameter of a heat exchange body can be, for example, 250 mm to 1 m or more. The adjacent sheet metal elements can then have distances of approximately 1 mm, for example, the thickness of the sheet metal elements being, for example, approximately 0.2 mm. The heat exchange body can then have at least 500 or even at least 1000 sheet metal elements and passages distributed around its axis. The large number of narrow passages results in an intensive heat exchange. The wire mesh also creates microturbulence in the fluids flowing through the passageways. This further improves the heat exchange between the two fluids.

The heat exchanger partially shown in FIGS. 13 to 16, like the heat exchanger described above, has one and only one ring-shaped heat exchange body 5. This is largely identical or similar to the previously described heat exchange body and in particular has an inner jacket surface 5a, one outer jacket surface 5b and two facing surfaces 5c, 5d. Furthermore, there are again holding members 41, 42 with walls 43, 44 for holding the heat exchange body 5 available. However, the lower holding member 41 is designed such that it completely covers the lower end surface 5c from the inner lateral surface 5a to the outer lateral surface 5b and closes the second passages more or less airtight everywhere. For this purpose, the upper holding member 42 at the upper end face 5d leaves both an annular region adjoining its inner edge and an annular region adjoining its outer edge. The second fluid 16 consisting of cold air can flow into the heat exchange body in the outer, uncovered ring area of the upper end face 5d and out of the heat exchange body in the inner, uncovered ring area of the same end face 5d. The second fluid 16 is thus guided along an approximately U-shaped flow path into the heat exchange body, through it and out of it again. This may be advantageous for reasons of space. In contrast, the first fluid 15 is passed through the heat exchange body analogously to the heat exchanger described with reference to FIGS. 1 to 12.

The heat exchanger according to FIGS. 13 to 16 also differs from the previously described heat exchanger in that for each end face 5c, 5d, instead of a single film 45 or 46, there are several along the circumference of the

There are heat exchange bodies, distributed metallic foils 75 and 76, which can be seen particularly clearly in FIGS. 14 and 15. Each involute-shaped sheet metal element and each fluid passage has parts at each end face 5c, 5d, which are covered by at least two different foils 75 and 76, respectively. The second fluid passages 34 are again open at the end faces 5c, 5d. The films 75, 76 abutting the end faces 5c, 5d overlap one another in such a way that the second fluid 16 when the films overlap each at an exit section of a film from the latter covered area emerges, in which this film is already covered by the film following in the flow direction of the second fluid.

In addition to a main section abutting the heat exchange body 5, each film 75, 76 also has edge sections 75a and 76a. In the heat exchanger according to FIGS. 13 to 16, each cavity delimited by one of the walls 43, 44 also contains an insulation 88 which is composed of two originally separate insulation parts 88a and 88b. The insulation part 88a consists of a flat layer which lies against the main sections of the foils 75 and 76, respectively. The edge sections 75a, 76a of the foils are folded around the edges of the insulation part 88a. The insulation parts 88b lie on the insulation parts 88a and the folded ones

Edge sections 75a, 76a of the foils clamp the folded edge portions thereby and serve to hold the foils in place.

16 also shows some welded connections, of which all those which connect the heat exchange body 5 to parts of the housing and / or the holding members and / or fluid guide means are designated by 91.

Unless otherwise stated in the foregoing, the heat exchanger according to FIGS. 13 to 16 can be of the same or similar design as the heat exchanger according to FIGS. 1 to 12.

The one shown in Figures 17, 18 and 19

Heat exchanger 101 has an axis 2 and a housing 103. The housing contains a first heat exchange body 105.1 and a second heat exchange body 105.2. Furthermore, only schematically shown fluid guide means 107 are present. 17 also shows parts of a gas turbine 112 can be seen, the housing of which is connected to the housing 103 and the fluid guide means 107 of the heat exchanger 101. Arrows e also show first fluid 15 consisting of exhaust gas and e second fluid 16 consisting of air.

Each heat exchange body 105.1, 105.2 has, around the axis 2, alternating successive, first and second fluid guide elements. The first fluid guide elements can be seen in FIG. 18 and are of identical design in the case of both heat exchange bodies 105.1, 105.2 and are also constructed identically or similarly to the first fluid guide elements of the heat exchange body 5 and as they are designated by 21. In contrast, the second fluid guide elements of the two heat exchange bodies 105.1, 105.2 shown in FIG. 19 are not very different from one another and are designated by 122.1 or 122.2. Each first and second fluid guide element has a first sheet metal element and a second sheet metal element as main components. The sheet metal elements are all of identical design and dimensions, and are also identical or similar to the sheet metal elements 23, 27 of the heat exchange body 5 and are designated as 23 and 27, respectively. The sheet metal elements of the heat exchange body 105.1, 105.2 are the same or similar to those of the heat exchange body 5 with first edge strips 24, 25 and second edge strips 28, 29 and are connected to one another in pairs.

First and second intermediate layers are alternately arranged between the sheet metal elements of the heat exchange bodies 105.1, 105.2 which follow one another around the axis. 18, the first intermediate layers of the two heat exchange bodies are all of the same design and arrangement, and are also of the same or similar design as those of the heat exchange body 5 and as they are designated by 31. Of the second intermediate layers shown in FIG. 19, the first heat exchange body 105.1 belonging to the same or similar design and arranged as those of the heat exchange body 5 and designated 32. The second intermediate layers of the second heat exchange body 105.2 are denoted by 132.2 and are arranged somewhat differently than the second intermediate layers 32 of the first heat exchange body 105. While each intermediate layer 32 is at least approximately adjacent to an edge strip 28 and by an axial, strip-shaped, free space from Edge strip 29 is separated, connects every second intermediate layer 132 at least approximately to edge strip 29 and is separated from edge strip 28 by a strip-shaped, free space.

The housing 103 has holding members 41 and 42 which are designed similarly to those of the housing 3, as they are designated 41 and 42, respectively. Each of these holding members acts on one of the two most distant, flat end surfaces 105.1c and 105.2d of the two heat exchange bodies 105.1, 105.2. An annular holding member 143 is arranged between the two heat exchange bodies. This has two short, cylindrical, metallic walls, namely an inner wall 144 and an outer wall 145 and two metallic foils 146, each of which rests on one of the mutually facing end surfaces 105. Ld or 105.2c of the two heat exchange bodies 105.1, 105.2 , The interior enclosed by the walls 144, 145 and the foils 146 contains a heat-insulating, elastically deformable insulation 147. The holding member 143 covers the largest parts of the end faces 105, ld, 105.2c of the two heat exchange bodies, but leaves inside and outside an annular area free.

First and second fluid passages are alternately present between the sheet metal elements which follow one another around the axis. 18 shown in FIG. The first fluid passages of the two heat exchange bodies 105.1, 105.2 are all of identical design and are of the same or similar design as those of the heat exchange body 5 and are denoted by 33.

The second fluid passages of the two heat exchange bodies 105.1, 105.2 are designated 134.1 and 134.2, respectively. Analogously to the second fluid passages 34 of the heat exchange body 34, the second passages 134.1 of the first heat exchange body 105 have a second fluid outlet opening 134.1a and a second fluid outlet opening 134.1b and additionally a fluid secondary outlet opening 134.1c , This is located at the end face 105. Ld of the body 105 and is arranged in the axial direction opposite the second inlet opening 134.1a.

Every second fluid passage 134.2 of the second heat exchange body 105.2 has a second fluid inlet opening 134.2a and a second fluid outlet opening 134.2b. These two openings are arranged similarly to the corresponding openings of the second passages of the heat exchange body 5. However, the section of the passage 134.2 which is axially aligned with the inlet opening 134.2a also contains a section of a second intermediate layer 132.2. Every second passage 134.2 of the second heat exchange body 105.2 also has a fluid secondary inlet opening 134.2c. This is located close to the inner edges of the second sheet metal elements of the second heat exchange body 105.2 and is located m the end face 105.2c. Each secondary inlet opening 134.2c is arranged in the axial direction opposite the second outlet opening 134.2b and is connected to it by an axial, strip-shaped region of the second passage 134.2 which is at least partially free, ie does not contain any section of the second intermediate layer 132.2. The housing 103 unr! the fluid guide means 107 are partially similar to the housing 3 and the fluid guide means 7, however, still delimit an inner and an outer connection passage 155 and 156, respectively. The inner connection passage 155 connects the one defined by the second outlet openings 134.1b , annular, second outlet area of the first heat exchange body 105.1 with the annular secondary inlet area of the second heat exchange body 105.2 defined by the secondary inlet openings 134.2c. The outer connecting passage 156 connects the annular secondary outlet area of the first heat exchange body 105.1 defined by the secondary outlet openings 134.1c to the annular second inlet area of the second heat exchange body 105.2 defined by the second inlet openings 134.2a.

When using the heat exchanger 101, originally hot exhaust gas flows as the first fluid 15 from the inside to the outside through the first passages 33 of the two heat exchange bodies 105.2 and 105.2. The second fluid 16, which originally consists of cold air, is passed through the second inlet openings 134.1a of the first heat exchange body 105.1 into the second passages 134.1 thereof and then flows partly through these passages inwards to the second outlet openings 134.1b and partly through the secondary outlet openings 134.1c and the outer connecting passage 156 to the second inlet openings 134.2a of the second heat exchange body 105.2 and through its second passages 134.2 inwards to the second one

Outlet openings 134.2b. That part of the second fluid 16 which reaches the second outlet openings 134.1b of the first heat exchange body 105.1 then flows through the inner connecting passage 155 to the secondary inlet openings 134.2c of the second heat exchange body 105.2 Output end areas of the second passages 134.2 of the second heat exchange body 105.2. There, the part of the second fluid 16 coming from the first heat exchange body 105.1 merges with that part of the second fluid which previously flowed through the entire second heat exchange body from the outside inwards. The combined parts of the second fluid 16 then flow out of the second heat exchange body 105.2 through the second outlet openings 134.2b.

Unless otherwise stated above, the heat exchanger 101 is of similar design and is used and operated in a similar manner to the heat exchanger 1 and has properties similar to this.

The heat exchanger 201 shown in FIG. 20 has a housing 203. This contains several, namely three pairs of heat exchange bodies. Each pair has a first heat exchange body 205.1 and a second heat exchange body 205.2. The heat exchange bodies 205.1 and 205.2 are configured similarly to the heat exchange bodies 105.1 and 105.2 of the heat exchanger 101. The three heat exchange body pairs are axially offset from one another and are kept at a distance from one another by holding members 206 arranged between them. These holding members 206 are, for example, similar to that

Holding members 143 of the heat exchanger 101 are formed, but have larger axial dimensions. The fluid guiding means 207 of the heat exchanger 201 are designed to conduct a first fluid 15 and a second fluid 16 in an analogous manner through the heat exchange bodies 205.1 and 205.2 belonging to the same pair, as is the case for the only pair of heat exchange bodies. Body heat exchanger 101 has been described. The heat exchanger 301 shown in FIG. 21 has several, namely, for example, four ring-shaped heat exchange bodies, which are designed in the same or a similar way to that of the heat exchanger described first and are also designated by 5. The ring-shaped heat exchange bodies are spaced apart from one another along axis 2 of the heat exchanger and enclose a cavity with an axial tube 303. The cavity area present between the inner lateral surfaces of the heat exchange body 5 and tube 303 serves as the first inlet chamber 351 for the first fluid 15 and contains some conical baffles 305 which have an opening in the central area and serve to distribute the first fluid to the various heat exchange bodies 5. The heat exchange bodies 5 have inlet openings for the second fluid 16 at each of their two end surfaces in the vicinity of the outer jacket surface and outlet openings for the second fluid 16 near the inner jacket surface. That at the upper end surface of the uppermost heat exchange body 5 of this outflowing, second fluid 16 arrives in an annular, second outlet chamber 354. The remaining, second fluid 16 flowing out of the heat exchange bodies arrives in annular, second outlet chambers 355, which are connected to the pipe 303 by radial, spoke-like connecting channels 356. This is in the vicinity of its upper end by some, for example inclined to axis 2,

Connecting channels 357 connected to the second outlet chamber 354, from which the second fluid 16 can flow out through an opening in the housing of the heat exchanger. The connecting channels 356 are composed of half shells. Furthermore, the remaining funds for

Holding the heat exchange body and for supplying the fluids to the heat exchange bodies and for draining the fluids from the heat exchange bodies largely modular, so that the number of identical heat exchange bodies can easily be changed and adapted to the intended fluid flow rates.

The heat exchangers can be modified in other ways. In particular, features of the various heat exchangers described can be combined with one another. The foils can, for example, be designed and held in a similar manner in all exemplary embodiments, as was described for the heat exchanger in accordance with FIGS. 13 to 16. In addition, in the

FIGS. 5 and 19, which serve as second intermediate layers 32, are knitted wires over the entire lengths of the second fluid passages 34, 134.1, 134.2 - i.e. from the inner to the outer edge strips. Furthermore, the wall 43 of the one shown in Figures 1 to 12

Heat exchanger possibly also at its outer edge facing the lower end face 5c - i.e. with the inner boundary of the second inlet area 5g - and / or the wall 44 also with its inner edge facing the upper end face 5d - i.e. at the outer boundary of the second outlet area 5h - be welded to the heat exchange body 5. In the heat exchanger shown in FIGS. 13 to 16, the wall 44 m could possibly be welded to the outer and / or inner end face 5d of the heat exchanger 5 in an analogous manner. The welded connections between the sheet metal elements and edge strips as well as between the heat exchange bodies and the parts of the housing and / or fluid guide means connected with them can possibly be at least partially or completely by brazing joints and / or

Adhesive connections to be replaced. For example, the first inlet openings and the second outlet openings of a heat exchange body could be axially offset in the inner lateral surface of the heat exchange body. The first outlet openings and the second inlet openings a heat exchange body could analog axially offset in the outer surface of the heat exchange body.

Furthermore, the sheet-metal elements in the developed, flat state could possibly form an oblique-angled parallelogram or have at least two mutually opposite, non-parallel edges. In these cases, at least one of the lateral surfaces and / or end surfaces of the heat exchange body would then be conical. Maybe they could

Sheet metal elements even have at least one edge bent in the developed, flat state of the sheet metal elements.

Claims

1. Heat exchanger with at least one heat exchange body (5, 105.1, 105.2, 205.1, 205.2) which is ring-shaped in cross section and which surrounds an axis (2) and has successive sheet metal elements (23, 27, 127) around it, which alternate together limit first passages (33) for a first fluid (15) and second passages (34, 134.1, 134.2) for a second fluid (16), each sheet metal element (23, 27, 127) having an inner edge (23a, 27a), one Has the outer edge (23b, 27b) and two side edges (23c, 23d, 27c, 27d) running from the inner edge (23a, 27a) to the outer edge (23b, 27b), with adjacent sheet metal elements (23, 27, 127) along their side edges ( 23c, 23d, 27c, 27d) have essentially constant distances from one another, characterized in that each sheet metal element (23, 27, 127) forms a square, that between the sheet metal elements (23, 27, 127 delimiting a first passage (33) together ) at the side edges (23c, 23d, 27c, 27d) of those running along them, metallic edge strips (24, 25) are arranged and firmly and tightly connected to the relevant sheet metal elements (23, 27, 127) and that between the sheet metal elements (23, 27, 127) delimiting a second passage (34, 134.1, 134.2) the inner edges (23a, 27a) and the outer edges (23b, 27b) of which metallic edge strips (28, 29) running along these are arranged and are firmly and tightly connected to the sheet metal elements (23, 27, 127) in question.

2. Heat exchanger according to claim 1, characterized in that the inner edge (23a, 27a) and the outer edge (23b, 27b) of each sheet metal element (23a, 27a) are straight and parallel to each other and that the two side edges (23c, 23d, 27c, 27d) of each sheet metal element (23, 27, 127) in parallel to each other and perpendicular to the inner edge (23a, 27a) and outer edge (23b, 27b).

3. Heat exchanger according to claim 1 or 2, characterized in that the sheet metal elements (23, 27, 127) by welding or brazing or gluing with the edge strips (24, 25, 28, 29) and thereby connected to each other.

4. Heat exchanger according to one of claims 1 to 3, characterized in that the first together

Sheet metal elements (23, 27, 127) delimiting passage (33) at their inner edges (23a, 27a) and outer edges (23b, 27b) between the edge strips (24, 25) arranged at their side edges (23c, 23d, 27c, 27d) of rigid connections between them.

5. Heat exchanger according to one of claims 1 to 4, characterized in that the two side edges (23c, 23d, 27c, 27d) of the sheet metal elements (23, 27, 127) and the edge strips (24, 25) extending along these run away from one another End surfaces (5c, 5d) form that the second passages (34, 134.1, 34.2) have inlet openings (34a, 134.1a, 134.2a) lying in one of the end surfaces (5c, 5d) and in one of the end surfaces (5c, 5d) Outlet openings (34b, 134.1b, 134..2b) have that the sheet metal elements (23, 27, 127) delimiting a second passage (34, 134.1, 134.2) at the side edges (23c, 23d, 27c, 27d) of these sheet metal elements (23, 27, 127) are free of rigid connections between them in at least one of the following areas; a) between the at their inner edges (23a, 27a) and

Edge strips (28, 29), b) arranged on the outer edges (23b, 27b) between the inlet openings (34a, 134.1a, 134.2a) and those on the inner edges (23a, 27a) Edge strips (28) and between the outlet openings (34b, 134. lb, 134.2b) and the edge strips (29), c) arranged at the outer edges (23b, 27b) between the inlet openings (34a) and the outlet openings (34b).

6. Heat exchanger according to one of claims 1 to 5, characterized in that each first passage (33) at the inner edges (23a, 27a) of the two sheet metal elements delimiting it (23, 27, 127) has at least one opening (33a) connects the first passage (33) between these inner edges (23a, 27a) with a space adjacent to them and that each first passage (33) at the outer edges (23b, 27b) of the two sheet metal elements (23, 27, 127) delimiting it has at least one opening (33b) which connects the first passage (33) between these outer edges (23b, 27b) with a space adjacent to them.

7. Heat exchanger according to one of claims 1 to 6, characterized in that every second passage (34, 134.1, 134.2) in the vicinity of the outer edges (23b, 27b) and in the vicinity of the inner edges (23a, 27a) of the two delimiting it Sheet metal elements (23, 27, 127) each have at least one opening (34a, 34b, 134.1a, 134.1b) which has the second passage (34, 134.1, 134.2) between two mutually opposite side edges (23c, 23d, 27c, 27d) connects these sheet metal elements (23, 27, 127) with a space adjacent to them.

8. Heat exchanger according to claim 7, characterized in that the openings of the passages (33, 34, 134.1, 134.2) located at or near the inner edges (23a, 27d) of the sheet metal elements (23, 27, 127) serve as inlet openings (33a) the first passages (33) or as outlet openings (34b,

134.1b, 134.2b) of the second passages (34, 134.1, 134.2) serve that the openings of the passages (33, 34, 134.1.) Located at or near the outer edges (23b, 27b) of the sheet metal elements (23, 27, 127) , 134.2) as outlet openings (33b) of the first passages (33) or as inlet openings (34a, 134.1a, 134.1b) of the second passages (34, 134.1, 134.2) serve that fluid guide means (7, 107, 207) are present in order to direct the first fluid (15) to the inlet openings (33a) of the first passages (33) as well as away from the outlet openings (33b) of the first passages (33) and to direct the second fluid (16) to the Directing inlet openings (34a, 134.1a, 134.1b) of the second passages (34, 134.1, 134.2) and leading away from the outlet openings (34b, 134.1b, 134.2b) of the second passages (34, 134.1, 134.2), and that the fluid guide means (7, 107, 207) are designed to supply the first fluid to the inlet openings (33a) of the first "passages (33) at a temperature which is high r is a temperature at which the second fluid (16) is supplied to the inlet openings (34a, 134.1, 134.2) of the second passages (34, 134.1, 134.2) so that the first fluid 825) supplies heat to the second fluid (16 ) and the or each heat exchange body (5, 105.1, 105.2, 205.1, 205.2) has a generally decreasing temperature away from the axis (2) towards the outside.

9. Heat exchanger according to claim 8, characterized in that the inlet openings (33a) of the first passages (33) at a first inlet region (5e), the outlet openings (33b) of the first passages (33) at a first outlet region (5f), the Inlet openings (34a, 134.1a,

134.2a) of the second passages (34, 134.1, 134.2) at a second inlet area (5g) and the outlet openings (34b, 134.1b, 134.2b) of the second passages (34, 134.1, 134.2) at a second outlet area (5h) from the or a heat exchange body (5, 105.1, 105.2, 205.1, 205.2) arranged and that each emission region (5e, 5g) and outlet region (5f, 5h) run in a ring around the axis (2).

10. Heat exchanger according to one of claims 1 to 9, characterized in that the inner edges (23a, 27a) of the sheet metal elements (23, 27, 127) and the edge strips (28) arranged on the inner edges (23a, 27a) have an inner jacket surface ( 5a) define that the mutually adjacent sheet metal elements (23, 27, 127) are at an approximately constant distance from one another from their inner edges (23a, 27a) to their outer edges (23b, 27b) and that the inner edges (23a, 27a) adjoining sections of the sheet metal elements (23, 27, 127) with a cross section perpendicular to the axis (2) have tangents which form an angle with the inner lateral surface (5a) which is 65 ° to 115 ° and, for example, 80 ° to 100 ° amounts, the sheet metal elements (23, 27, 127) preferably being substantially involute in a section perpendicular to the axis (2).

11. Heat exchanger according to one of claims 1 to 10, characterized in that the side edges (23c, 23d, 27c, 27d) of the sheet metal elements (23, 27, 127) and the side edges (23c, 23d, 27c, 27d) are arranged Edge strips (24, 25) define two end faces (5c, 5d) of the or each heat exchange body (5, 105.1, 105.2, 205.1, 205.2) and that the inlet openings (34a, 134.1a, 134.2a) and the outlet openings (34b , 134.1b, 134.2b) of the second passages (34, 134.1, 134.2) are arranged at end faces (5c, 5d) facing away from one another.

12. Heat exchanger according to claim 11, characterized in that it has at least em heat exchange body pair with a first heat exchange body (105.1, 205.1) and a second heat exchange body (105.2, 205.2), that each heat exchange body (105.1, 105.2, 205.1, 205.2) has an inner and an outer jacket surface, that the second passages (134.1) with the in an end surface (105.1c ) of the first heat exchange body (105.1, 205.1) arranged inlet openings (134.1a) m of the other end surface (105. ld) in the vicinity of the outer jacket surface of the first heat exchange body (105.1, 205.1) arranged secondary outlet openings (134.1c) have that the second passages (134.2) with the outlet openings (134.2b) of the second heat exchange body (105.2, 205.2) arranged in one end face (105.2c) in the other end face (105.2c) near the inner lateral surface of the second Have heat exchange bodies (105.2, 205.2) arranged secondary inlet openings (134.2c) and that the fluid guide means (107, 207) are designed to hold the second fluid (16) at the inlet openings arranged in an end face (105.1c) ( 134.1a) the second passages (134.1) into the first heat exchange body (105.1) and then part of this fluid (16) from the secondary outlet openings (134.1c) of the first heat exchange body (105.1) to those in an end face (105.2c) arranged second inlet openings (134.2a) of the second heat exchange body (105.2, 205.1) and to guide second fluid (16) which emerges from the m of an end face (105. ld) of the first heat exchange body (105.1, 205.1) arranged, second outlet openings (134.1b) flows out to the secondary inlet openings (134.2c) of the second heat exchange body (105.2, 205.2).

13. Heat exchanger, in particular according to one of claims 1 to 12, with at least one heat exchange body (5, 105, 105.2, 205.1, 205.2) with successive sheet metal elements (23, 27, 127), the alternating passages (33, 34, 134.1, 134.2) for a first fluid (15) and a second fluid (16) and between which gas-permeable intermediate layers (31, 32, 132.2) are arranged, each sheet metal element (23, 27, 127) having two mutually facing side edges (23c, 23d, 27c, 27d), characterized in that the side edges (23c, 23d, 27c, 27d) those belonging to the same heat exchange body (5, 105.1, 105.2, 205.1, 205.2)

Sheet metal elements (23, 27, 127) and / or edge strips (24, 25) arranged at these side edges (23c, 23d, 27c, 27d) together two end faces (5c, 5d, 105.1c, 105. ld, 105.2c, 105.2d ) of the heat exchange body (5, 105.1, 105.2, 205.1, 205.2) define that at each end face (5c, 5d, 105.1c, 105. ld, 105.2c, 105.2d) at least one metallic foil (45, 46, 75 , 76, 146) on the side edges (23c, 23d, 27c, 27d) of the sheet metal elements (23, 27, 127) and that a heat insulating insulation (47, 48, 88, 147) on the sheet metal elements (23, 27, 127) facing away from each film (45, 46, 75, 76, 146) is arranged.

14. Heat exchanger according to claim 13, characterized in that each foil (45, 46, 75, 76, 146) is at most 0.1 mm. And for example 0.03 mm to 0.07 mm thick.

15. Heat exchanger according to claim 12 or 13, characterized in that the insulation (47, 48, 88, 147) presses the film (45, 46, 75, 76, 146) against the sheet metal elements (23, 27, 127), wherein the insulation (47, 48, 88, 147) is elastically deformable, for example.

16. Heat exchanger according to one of claims 13 to 15, characterized in that at each end face (5c, 5d,

105.1c, 105. ld, 105.2c, 105.2d) of the or each heat exchange body (5, 105.1, 105.2, 205.1, 205.2) there are at least two foils (75, 76) which are provided on the end face (5c, 5d , 105.1c, 105. ld, 105.2c, 105.2d) have adjacent, overlapping sections.

17. Heat exchanger, in particular according to one of claims 1 to 16, with at least one heat exchange body (5, 105.1, 105.2, 205.1, 205.2) which is annular in cross section and which surrounds an axis (2) and sheet metal elements (23 , 27, 127), which together alternately delimit first passages (33) for a first fluid (15) and second passages (34, 134.1, 134.2) for a second fluid (16), each sheet metal element (23, 27, 127 ) has an inner edge (23a, 27a), an outer edge (23b, 27b) and two side edges (23c, 23d, 27c, 27d) running from the inner edge (23a, 27a) to the outer edge (23b, 27b), with mutually adjacent sheet metal elements ( 23, 27, 127) along their side edges (23c, 23d, 27c, 27d) have essentially constant distances from one another, the passages

(33, 34, 134.1, 134.2) between openings (33a, 134.1b, 134.2b, 134.2c) near the inner edges (23a, 27a) and openings (33b, 34a, 134.1a, 134.1c, 134.2a) extend in the vicinity of the outer edges (23b, 27b), characterized in that the sheet metal elements (23, 27, 127) one along their

Side edges (23c, 23d, 27c, 27d) have a dimension which is at least twice a dimension of the sheet metal elements (23, 27, 127) measured along the axis (2).

18. Heat exchanger according to claim 17, characterized in that it has at least two heat exchange bodies (105.1, 105.2, 205.1, 205.2) spaced apart from one another along the axis (2).

19. Heat exchanger according to claim 17 or 18, characterized in that the distance from adjacent sheet metal elements (23, 27, 127) is at most 10 mm and preferably at most 2 mm.

20. Heat exchanger according to one of claims 17 to 19, characterized in that the or each heat exchange body (5, 105, 105.2, 205.1, 205.2) at least 500 passages (33, 34, 134.1) distributed around the axis (2) , 134.2).

21. Heat exchanger, in particular according to one of claims 1 to 20, with at least one heat exchange body (5, 105, 105.2, 205.1, 205.2) with successive sheet metal elements (23, 27, 127), the alternating passages (33, 34, 134.1,

134.2) for the first fluid (15) and the second fluid (16) and between which gas-permeable intermediate layers (31, 32, 132.2) are arranged, each sheet metal element (23, 27, 127) having two mutually facing side edges ( 23c, 23d, 27c, 27d) and at least substantial parts of the passages (33, 34, 134.1, 134.2) run along the side edges (23c, 23d, 27c, 27d), characterized in that each intermediate layer (31, 32, 132.2 ) consists of a knitted wire (37) which has rows of stitches (37a) with adjacent stitches (37b) formed from interconnected wire sections and that these rows of stitches (37a) are generally approximately at right angles to the side edges (23c, 23d, 27c, 27d) of the sheet metal elements (23, 27, 127).

22. The heat exchanger according to claim 21, characterized in that each wire knitted fabric (37) is attached in places to one and only to a sheet metal element (23, 27) adjacent to it, wherein, for example, each wire knitted fabric (37) is secured by a few spot welds sheet metal element (23, 27) adjacent to it is fastened.

23. Heat exchanger according to claim 21 or 22, characterized in that two rows of stitches (37a) following one another along the side edges (23c, 23d, 27c, 27d), apart from the intermeshed meshes (37b), at most have a single contiguous wire section.

24. Heat exchanger according to one of claims 21 to 23, characterized in that the or each heat exchange body (5, 105.1, 105.2, 205.1, 205.2) encloses an axis (2) and is annular in a cross section perpendicular to this that Each sheet metal element (23, 27, 127) has an inner edge (23a, 27a) and an outer edge (23b, 27b) that the side edges (23c, 23d, 27c, 27d) from the inner edge (23a, 27a) to the outer edge (23b , 27b) and form an angle with the axis (2) that mutually adjacent sheet metal elements (23, 27, 127) have substantially constant distances from one another along the entire length of their side edges (23c, 23d, 27c, 27d) and that the passages (33, 34, 134.1, 134.2) along at least the largest parts of the side edges (23c, 23d, 27c, 27d) of the sheet metal elements (23, 27, 127) are closed.

25. Heat exchanger according to claim 24, characterized in that around the axis (2) alternately a first passage (33) for the first fluid (15) and a second passage (34, 134.1, 134.2) for the second fluid (16) in succession that with each first passage (33) along the side edges (23c, 23d, 27c, 27d) of the sheet metal elements (23, 27, 127) delimiting this first passage (33), edge strips (24, 25) extending between the two sheet metal elements (23, 27, 127 arranged and firmly and tightly connected to the latter and that every second pass (34, 134.1, 134.2) along the inner edges (23a, 27a) and along the outer edges (23b, 27b) of this second pass (34, 134.1, 134.2) bordering sheet metal elements (23, 27, 127) edge strips (28, 29) arranged between the sheet metal elements (23, 27, 127) and firmly and tightly connected to the latter.

26. Heat exchanger according to claim 24 or 25, characterized in that the mutually adjacent sheet metal elements (23, 27, 127), apart from at most with edges (23a, 23b, 23c, 23d, 27a, 27b, 27c, 27d) with them edge strips (24, 25, 28, 29) connected to them and arranged between adjacent sheet metal elements (23, 27, 127), everywhere at least approximately constant distance apart, completely smooth in the axial direction, straight and parallel to one another and perpendicular to the axis (2) running cuts are completely parallel to one another and are smooth and, for example, essentially involute, so that the sheet metal elements (23, 27,

127) are free of elevations and depressions, such as waves and / or ribs and the like, and of angled and / or bent edge sections.

27. Heat exchanger according to one of claims 21 to 26, characterized in that each sheet metal element (23, 27, 127) has a thickness which is at most 5 mm, suitably at most 1 mm, preferably at most 0.5 mm and for example at most 0, 3 mm, and that the knitted wire (37) consist of wires whose thickness is at most 5 mm, expediently, at most 1 mm, preferably at most 0.8 mm and, for example, 0.3 mm to 0.7 mm, where the sheet metal elements (23, 27, 127) and wire mesh (37) are preferably made of stainless steel.