Abstract
A heat exchanger, in particular an oil-air cooler, for heat exchange between a first fluid and a second fluid, having at least a first row and a second row of tubular elements for the first fluid, a flow channel for the second fluid between the first and second rows of tubular elements; a collection vessel at one end of the tubular elements; and a distribution vessel at the other end of the tubular elements. Guiding elements for guiding the second fluid extend along the flow channel between the outer sides of adjacent tubular elements of the first and second rows of tubular elements. At least one adjustment device is provided for adjusting the relative position of two guiding elements about a pivot axis.
Claims
1. A heat exchanger, for heat exchange between a first fluid and a second fluid, having at least a first row of tubular elements and a second row of tubular elements, each for passage of the first fluid, wherein a flow channel for the second fluid is formed between the first and the second row of tubular elements, with a collection vessel at the one ends of the tubular elements and with a distribution vessel at the other ends of the tubular elements, wherein guiding elements for guiding the second fluid along the flow channel extend between the outer sides of adjacent tubular elements of the first and second row of tubular elements, the guiding elements each comprising a plate part the wall thickness of which is less than the maximum cross-sectional dimension of the tubular elements connected thereto, wherein at least one adjustment device is provided for adjusting the relative position of two guiding elements about a pivot axis extending essentially in direction of the longitudinal axes of the tubular elements, wherein the flow channel comprises an input end and an output end, and main extension directions of at least two adjacent flow channels enclose an angle (γ) between each other, the angle (γ) deviating from 0°, wherein a main extension direction of a flow channel is the direction from the input end to the output end of the flow channel.
2. The heat exchanger according to claim 1, wherein holding devices are provided in order to connect adjacent tubular elements of the first or second row of tubular elements with each other via the guiding elements.
3. The heat exchanger according to claim 1, wherein two wing parts protrude from the outer side of each tubular element, wherein two wing parts on adjacent tubular elements of the first or second row of tubular elements together form one guiding element of the guiding elements for the second fluid.
4. The heat exchanger according to claim 3, wherein each wing part comprises a connection element of the holding device, which together form a joint of the adjustment device.
5. The heat exchanger according to claim 4, wherein spiral-shaped bent edges of the wing parts are provided as connection elements.
6. The heat exchanger according to claim 1, wherein the guiding elements each comprise a joint portion of the adjustment device, which joint portion is rotatably arranged about at least one of the tubular elements connected to the guiding element.
7. The heat exchanger according to claim 1, wherein the tubular elements of the first and second row of tubular elements and the guiding elements are arranged relative to each other such that the main extension directions of at least two adjacent guiding elements of the first or second row of tubular elements, in a plane essentially at right angles to the longitudinal axes of the tubular elements, enclose an angle (η, ζ, ε) deviating from 180°.
8. The heat exchanger according to claim 7, wherein the arrangement of tubular elements of the first or second row of tubular elements and of the at least two adjacent guiding elements enclosing the angle (η, ζ, ε) deviating from 180°, in the first or second row of tubular elements, repeats at regular intervals.
9. The heat exchanger according to claim 1, wherein the arrangement of tubular elements of the first or second row of tubular elements and of the guiding elements in a plane essentially at right angles to the longitudinal axes of the tubular elements forms an essentially undulating course of the flow channel.
10. The heat exchanger according to claim 9, wherein the plate parts each comprise arched, outer surfaces.
11. The heat exchanger according to claim 1, wherein the arrangement of tubular elements of the first or second row of tubular elements and of the guiding elements in a plane essentially at right angles to the longitudinal axes of the tubular elements forms an essentially zigzag-shaped course of the flow channel.
12. The heat exchanger according to claim 1, wherein the tubular elements of the first and second row of tubular elements are arranged offset from one another in flow direction of the second fluid.
13. The heat exchanger according to claim 1, wherein at least one guiding element comprises at least one plate body protruding therefrom.
14. The heat exchanger according to claim 1, wherein the collection vessel and/or the distribution vessel in a virtual cutting plane essentially at right angles to the longitudinal axes of the tubular elements is essentially rectangular, circular-ring-segment-shaped or circular-ring-shaped.
15. The heat exchanger according to claim 1, wherein the collection vessel and/or the distribution vessel in a virtual cutting plane essentially at right angles to the longitudinal axes of the tubular elements is essentially circular-ring-segment-shaped or circular-ring-shaped, wherein the main extension direction of the flow channel extends at an angle (φ) deviating from 0° to the radial direction of the collection vessel and/or to the radial direction of the distribution vessel, said radial direction extending from the beginning or the end of the flow channel.
16. The heat exchanger according to claim 15, wherein said angle is between 30° and 60°.
17. The heat exchanger according to claim 1, wherein the heat exchanger is an oil-air-cooler.
18. The heat exchanger according to claim 1, wherein detachable holding devices are provided in order to connect adjacent tubular elements of the first or second row of tubular elements with each other via the guiding elements.
19. The heat exchanger according to claim 1, wherein the plate parts each comprise circular-segment-shaped curved outer surfaces.
20. A heat exchanger, for heat exchange between a first fluid and a second fluid, having at least a first row of tubular elements and a second row of tubular elements, each for passage of the first fluid, wherein a flow channel for the second fluid is formed between the first and the second row of tubular elements, with a collection vessel at the one ends of the tubular elements and with a distribution vessel at the other ends of the tubular elements, wherein guiding elements for guiding the second fluid along the flow channel extend between the outer sides of adjacent tubular elements of the first and second row of tubular elements, the guiding elements each comprising a plate part the wall thickness of which is less than the maximum cross-sectional dimension of the tubular elements connected thereto, wherein at least one adjustment device is provided for adjusting the relative position of two guiding elements about a pivot axis extending essentially in direction of the longitudinal axes of the tubular elements, wherein the collection vessel and/or the distribution vessel in a virtual cutting plane essentially at right angles to the longitudinal axes of the tubular elements is essentially circular-ring-segment-shaped or circular-ring-shaped.
21. A heat exchanger, for heat exchange between a first fluid and a second fluid, having at least a first row of tubular elements and a second row of tubular elements, each for passage of the first fluid, wherein a flow channel for the second fluid is formed between the first and the second row of tubular elements, with a collection vessel at the one ends of the tubular elements and with a distribution vessel at the other ends of the tubular elements, wherein guiding elements for guiding the second fluid along the flow channel extend between the outer sides of adjacent tubular elements of the first and second row of tubular elements, the guiding elements each comprising a plate part the wall thickness of which is less than the maximum cross-sectional dimension of the tubular elements connected thereto, wherein at least one adjustment device is provided for adjusting the relative position of two guiding elements about a pivot axis extending essentially in direction of the longitudinal axes of the tubular elements, wherein holding devices are provided in order to connect adjacent tubular elements of the first or second row of tubular elements with each other via the guiding elements, wherein two wing parts protrude from the outer side of each tubular element, wherein two wing parts on adjacent tubular elements of the first or second row of tubular elements together form one guiding element for the second fluid, wherein each wing part comprises a connection element of the holding device, which together form a joint of the adjustment device, wherein spiral-shaped bent edges of the wing parts are provided as connection elements.
Description
(1) The invention will now be explained further by way of preferred non-restrictive exemplary embodiments with reference to the drawings, in which
(2) FIG. 1A shows an oblique view of a heat exchanger according to the invention with tubular elements for a first fluid and guiding elements arranged in between for a second fluid;
(3) FIG. 1B shows the heat exchanger of FIG. 1A in a view from the front;
(4) FIG. 1C shows a sectional view through the heat exchanger of FIG. 1B along a cutting line A-A;
(5) FIG. 2 shows the heat exchanger of FIG. 1A in an exploded view;
(6) FIGS. 3A to 3D show an embodiment of an adjustment device and a holding device for the heat exchanger as per FIGS. 1A to 1C and FIG. 2 in an oblique view (FIG. 3A), a detail view from above (FIG. 3B), a detail view of the holding device (FIG. 3C) and a detail view of a tubular element (FIG. 3D);
(7) FIG. 3E shows an arrangement of tubular elements and guiding elements for the heat exchanger as per FIGS. 1A to 1C and FIG. 2, in which the main extension directions of two adjacent guiding elements of a same row of tubular elements are pivoted against each other;
(8) FIGS. 4A and 4B show a further embodiment of an adjustment device and a holding device for the heat exchanger as per FIGS. 1A to 1C and FIG. 2 in an oblique view (FIG. 4A) and in a view from above (FIG. 4B);
(9) FIG. 5 shows an arrangement of tubular elements and guiding elements for the heat exchanger as per FIGS. 1A to 1C and FIG. 2, in which the main extension directions of two adjacent guiding elements of a same row of tubular elements are pivoted against each other;
(10) FIG. 6 shows an arrangement of tubular elements and guiding elements for the heat exchanger as per FIGS. 1A to 1C and FIG. 2, in which the flow channel has an undulating course;
(11) FIG. 7 shows a further arrangement of rows of tubular elements, which in this embodiment are arranged offset against each other in the main extension direction of the flow channel;
(12) FIG. 8A shows a further arrangement of rows of tubular elements with plate bodies protruding from the guiding elements, in a view from above;
(13) FIG. 8B shows a detailed oblique view of a section of a row of tubular elements with plate bodies protruding from the guiding elements;
(14) FIGS. 9A and 9B show two embodiments of a heat exchanger, in which the main extension directions of respectively two adjacent flow channels enclose an angle deviating from 0°;
(15) FIG. 10 shows an arrangement of rows of tubular elements in a circular-ring-segment-shaped collection baseplate of collection vessel, wherein the main extension direction of the flow channel extends obliquely to the radial direction of the collection vessel; and
(16) FIGS. 11A and 11B show two further embodiments of the collection vessel or of the distribution vessel with tubular elements and guiding elements pivoted against each other.
(17) FIG. 1A shows a heat exchanger 1 in a view obliquely from above, which in particular may be an oil-air-cooler. The heat exchanger 1 is used for heat exchange between a first fluid F1 and a second fluid F2 and comprises at least a first row R1 of tubular elements 2 and a second row R2 of tubular elements 2. The first fluid F1, for example oil, flows through the tubular elements 2. To facilitate heat exchange, a flow channel 3 for the second fluid F2, for example air, is formed between the first row R1 and the second row R2 of tubular elements 2. The heat exchanger 1 may be used as a liquid-air-cooler for cooling a liquid such as oil as a first fluid F1 by means of the cooling air, as a second fluid F2 or as a liquid-air heating device for the warming of air as the second fluid F2 by means of the warming liquid such as oil as the first fluid F1. The heat exchanger 1 also comprises a collection vessel 4 at the one ends ES of the tubular elements 2 and a distribution vessel 5 at the other ends EV of the tubular elements 2. At a connection point AZ (FIG. 2) the distribution vessel 5 is connected to a feed pipe not shown, through which the first fluid F1 is fed to the distribution vessel 5, which distributes the fed-in first fluid F1 at the ends EV among the tubular elements 2. At the other ends ES of the tubular elements 2 the first fluid F1 again exits from the tubular elements 2 and is directed into the collection vessel 4 connected to the ends ES. The collection vessel 4 is connected at a connection point AA (FIG. 2) to a discharge pipe not shown. The distribution vessel 5 comprises a distribution box 5A and a distribution baseplate 5C received therein. Correspondingly the collection vessel 4 comprises a collection box 4A and a collection baseplate 4C received therein. When the first fluid F1 is a liquid, for example oil, a liquid pump or oil pump not shown may be provided. The second fluid F2, for example air, may be conveyed through the flow channels 3 by means of a fan not shown. The heat exchanger 1 also comprises side parts 6A, 6B with through openings 6C for attaching the heat exchanger 1 to a carrier body not shown. The tubular elements 2 are essentially circular-shaped in cross-section and thus comprise a cylindrical shape. A cross-sectional view of a tubular element 2 is for example depicted in FIG. 3B. The cylindrical tubular elements 2 have a smooth outer surface 2A which is essentially free from indentations and elevations. Ribs 2V are preferably provided in the interior 21 of the cylindrical tubular elements 2. Guiding elements 7 are provided in order to be able to guide the second fluid F2 along the flow channel 3 between the first row R1 and the second row R2 of the tubular elements 2. The guiding elements 7 respectively extend between the outer sides 2A of two adjacent tubular elements 2M, 2N of the first row R1/the second row R2 of tubular elements 2. The rows RN, e.g. R1, R2, of tubular elements 2 thus comprise the tubular elements 2, between which the guiding elements 7 extend. The guiding elements 7 each comprise a plate part 8, the wall thickness 8W of which is less than the largest cross-sectional dimension of the tubular elements 2 connected thereto, i.e. is less, in the case of the cylindrical tubular elements, than the outer diameter 2D of the tubular elements 2 connected thereto, see for example FIG. 4B. The flow channel 3 for the second fluid F2 is thus formed by means of the walls W, which are formed from the outer sides 2A of the tubular elements 2 and the guiding elements 7 arranged between them of a first row R1 of tubular elements 2 and by means of the walls W, which are formed from the outer sides 2A of the tubular elements 2 and the guiding elements 7 arranged between them of a second row R2 of tubular elements 2.
(18) Although in the description reference is made to a flow channel 3 for the second fluid F2, which is formed between the first row R1 and the second row R2 of tubular elements 2, it should be remembered that the heat exchanger 1 can of course comprise more than two rows R1, R2 of tubular elements 2. For example, the heat exchanger 1 can comprise between 10 and 100, for example between 30 and 80 rows RN of tubular elements 2. A flow channel 3 is formed between two adjacent rows R1, R2 of tubular elements 2. A heat exchanger 1 with n rows RN of tubular elements 2 thus comprises n−1 flow channels 3. The features which refer to a flow channel 3 and a first row R1 and a second row R2 of tubular elements 2, therefore also apply to any additional, preferably to all envisaged flow channels 3 and rows RN of tubular elements 2. Preferably at least one further row RX of tubular elements 2 is provided, which in particular is designed corresponding to the first row R1 or the second row R2 of tubular elements 2.
(19) As revealed in the examples depicted in FIGS. 3A to 3E, 4A and 4B, at least one adjustment device 30 is provided for changing the relative position of two guiding elements 7 during assembly of the heat exchanger about a pivot axis 31 extending essentially in direction of the longitudinal axes L of tubular elements 2. By means of the adjustment device 30, the guiding elements 7 connected to the adjustment device 30 can therefore be adjusted, in particular pivoted against each other. Depending on the position of the adjustment device 30 the walls W of adjacent rows RN of tubular elements 2 can extend in parallel to one another or, at least in sections, enclose between them an angle deviating from 0°. The heat exchanger 1 may comprise a single adjustment device 30 or one or more adjustment devices 30 per row RN of tubular elements 2. In particular each combination of one tubular element 2 and a guiding element 7 connected thereto may comprise an adjustment device 30 in order to, in particular, permit high flexibility in designing the flow channels 3.
(20) As moreover revealed in the examples depicted in FIGS. 3A to 3E, 4A and 4B, holding devices 12 are provided in order to connect adjacent tubular elements 2M, 2N of the first or second row R1, R2 of tubular elements 2 with each other via the guiding elements 7. The holding devices 12 are preferably detachable holding devices 12A, in particular plug-in connections 12B. In the examples shown in FIGS. 3A to 3E, 4A and 4B, the holding devices 12 are, at the same time, the adjustment devices 30, i.e. the holding devices 12 also serve to adjust the relative position of two guiding elements 7 about a pivot axis 31 extending essentially in direction of longitudinal axes L of the tubular elements 2. The relative position of two guiding elements 7 may be understood to be the identical or different course of two cutting lines, which are created when the two guiding elements 7 intersect a plane E essentially at right angles to the longitudinal axes L of the tubular elements 2. If two guiding elements 7 comprise different positions, orientation of the guiding elements 7 may be different from one another, wherein the orientation of a guiding element 7 is defined by the virtual connection line between the two end points of the guiding element 7 or between the tubular elements 2 connected thereto. Similarly the orientation of two guiding elements 7 may be the same, but the course of the two guiding elements 7 between their end points may be different if the two guiding elements 7 comprise different positions.
(21) As further revealed in the examples shown in FIGS. 3A to 3E, 4A and 4B, two wing parts 13A, 13B protrude from the outer side 2A of each tubular element 2. Two wing parts 13B, 13C on adjacent tubular elements 2M, 2N of the first or second row R1, R2 of tubular elements together, i.e. preferably in a connected state, form a guiding element 7 for the second fluid F2. In order to be able to connect the wing parts 13A, 13B with each other, each wing part 13A, 13B in the examples shown comprises a connection element 14A, 14B of the holding device 12, 12A, 12B. The connection elements 14A, 14B together form a joint 32 of the adjustment device 30, with which joint 32 the relative position of two guiding elements 7 connected to the joint 32 can be adjusted/with which joint 32 the relative position of the two wing parts 13A, 13B connected to the joint 32 and which together form a guiding element 7, can be adjusted. The joint 32 is thus arranged in the guiding element 7. The connection elements 14A, 14B in the depicted examples are configured as spiral-shaped curved edges of the wing parts 13A, 13B, the edges being configured for mutually rotatably engaging with each other. Conveniently the spiral-shaped curved edges are configured to be pushed into each other in order to form a plug-in connection 12B.
(22) In FIGS. 3A and 3B a combination of tubular elements 2 and guiding elements 7 is shown, in which the guiding elements 7 or the wing parts 13A, 13B which together form a guiding element 7 enclose an angle of 180°, i.e. essentially point in the same direction. In this way a flow channel 3 with parallel walls W can be created. FIG. 3E by comparison shows a combination of tubular elements 2 and wing parts 13A, 13B, in which the wing parts 13A, 13B of different tubular elements 2 together enclose an angle deviating from 180°, i.e. essentially point in different directions. In addition, in FIG. 3E, dotted lines indicate a position of a tubular element 2 and of wing parts 13A, 13B connected therewith adjusted by an angle θ by means of the adjustment device 30.
(23) FIGS. 4A and 4B show another embodiment of the adjustment device 30, which is simultaneously formed as a holding device 12. Here the guiding elements 7 each comprise a joint portion 32A of the adjustment device 30, which joint portion 32A is rotatably arranged about at least one of the tubular elements 2 connected to the guiding element 7. The tubular element 2 serves as a second joint portion, which together with the joint portion 32A of the guiding element 7 forms a joint 32. The guiding element 7 can thus be rotated/pivoted about the tubular element 2 which engages the joint portion 32A of the guiding element 7. The joint portion 32A of the adjustment device 30 for example may be configured as a clamp which can be snapped onto a tubular element 2. FIG. 4B clearly shows that the guiding elements 7, by means of the adjustment device 30, enclose an angle deviating from 180°/can be pivoted about an angle α relative to a main extension direction 3H of the flow channel 3.
(24) Among others, in FIGS. 1C, 5, 6, 9A and 9B an arrangement of tubular elements 2 of the first and second rows R1, R2 of tubular elements 2 and of guiding elements 7 is recognisable, in which the main extension directions 7H of at least two adjacent guiding elements 7 of the first and second rows R1, R2 of tubular elements 2, in a plane E essentially at right angles to the longitudinal axes L of the tubular elements 2, enclose an angle η, ζ, ε deviating from 180°. The angles η, ζ, ε between the main extension directions 7H of respectively two adjacent guiding elements 7 may, by means of the adjustment device 30, be set to different sizes, as for example shown in FIG. 5. FIG. 1C by comparison, shows an embodiment, in which the angles η, ζ, ε deviating from 180° between the main extension directions 7H of respectively two adjacent guiding elements 7 are of identical size. FIG. 1C indicates that the arrangement of tubular elements 2 of the first or second rows R1, R2 of tubular elements 2 and of the at least two adjacent guiding elements 7 in the first or second row R1, R2 of tubular elements 2, which guiding elements 7 enclose the angle η deviating from 180°, repeats at regular intervals 10.
(25) FIG. 6 shows an embodiment of a flow channel 3 having a substantially undulating course, viewed in a plane E essentially at right angles to the longitudinal axes L of the tubular the elements 2, which is formed by a corresponding arrangement of tubular elements 2 of the first or second row R1, R2 of tubular elements 2 and of the guiding elements 7. The plate parts 8 of the guiding elements 7 in this example respectively comprise arched, in particular circularly arched outer surfaces 8A.
(26) For clarity's sake the adjustment device 30 and the holding device 12 are not shown in FIG. 6. Here as well, the adjustment device 30 and the holding device 12 may be configured as a joint assembly, i.e. may be identical, or one of the adjustment device 30 and the holding device 12 may be provided in the guiding element 7 and the other of the adjustment device 30 and the holding device 12 may be provided at the connection point of the guiding element 7 and the tubular element 2.
(27) Among others, FIGS. 1C, 9A and 9B show an embodiment of a flow channel 3 having an essentially zigzag-shaped course, viewed in a plane E essentially at right angles to the longitudinal axes L of the tubular elements 2, which is formed by a corresponding arrangement of the tubular elements 2 of the first and second row R1, R2 of tubular elements 2 and of the guiding elements 7, by means of the adjustment device 30.
(28) FIG. 7 shows an embodiment of a flow channel 3, in which the tubular elements 2 of the first and second rows R1, R2 of tubular elements 2 are arranged offset to one another in flow direction of the second fluid F2. The tubular elements 2 of a row RX are arranged opposite the guiding elements 7 or plate parts 8 of an adjacent row RX+1.
(29) In FIGS. 8A and 8B it can be clearly recognised that at least one guiding element 7, preferably a number of or all guiding elements 7, comprises/comprise at least one plate body 11 protruding therefrom. The plate body 11 protrudes into the flow channel 3 and thereby enlarges the area of the guiding element 7. The plate body 11 is arranged at the guiding element 7/the plate part 8 at an angle β different from 90°, in particular in flow direction S of the second fluid F2, at an acute angle β of between 30 and 60 degrees, for example, to the guiding element 7/the plate part 8. Here as well, at least one adjustment device 30 (not shown) may be provided.
(30) FIG. 9A shows a collection vessel 4 and its collection base plate 4C or a distribution vessel 5 and its distribution baseplate 5C, which are essentially rectangular, when viewed in a virtual cutting plane E essentially at right angles to the longitudinal axes L of the tubular elements 2. In particular the main extension directions 3H1, 3H2 of at least two adjacent flow channels 3X, 3Y enclose an angle γ deviating from 0°. In order to adjust the different main extension directions 3H1, 3H2 of the flow channels 3X, 3Y, the angles η, ζ, ε between the main extension directions 7H of respectively two adjacent guiding elements 7 of a row RN of tubular elements 2 may be chosen to be of different sizes. For example the flow channels 3, which enclose an angle γ deviating from 0°, may widen from their inlet or beginning 3A towards their outlet or end 3E. In the example shown in FIG. 9A the two guiding elements 7 of rows R1 and R2, which guiding elements 7 are next to the end 3E of the flow channel 3 enclose an angle δ deviating from 0°.
(31) FIG. 9B shows a collection vessel 4 and its collection baseplate 4C or a distribution vessel 5 and its distribution baseplate 5C, which are essentially trapeze-shaped, when viewed in a virtual cutting plane E essentially at right angles to the longitudinal axes L of the tubular elements 2. Here as well the main extension directions 3H1, 3H2 of at least two adjacent flow channels 3X, 3Y enclose an angle γ deviating from 0°.
(32) FIG. 10 shows a collection vessel 4 and its collection baseplate 4C or a distribution vessel 5 and its distribution baseplate 5C, which are essentially circular-segment-shaped when viewed in a virtual cutting plane E essentially at right angles to the longitudinal axes L of the tubular elements 2. It can be recognised that the main extension direction 3H of the flow channel 3 extends at an angle φ deviating from 0° in particular at an angle φ between 30° and 60° to the radial direction 4R of the collection vessel 4 or to the radial direction 5R of the distribution vessel 5. The radial direction 4R, 5R extends from the beginning 3A or end 3E of the flow channel 3.
(33) FIG. 11A shows a collection vessel 4 and its collection base plate 4C or a distribution vessel 5 and its distribution baseplate 50, which are essentially curved, wherein two rectangular end regions are connected to each other via a circular-segment-shaped region when viewed in a virtual cutting plane E essentially at right angles to the longitudinal axes L of the tubular elements 2. The directions indicated by arrows of the second fluid F2 during entry into the flow channel 3 and during exit from the flow channel 3 enclose an angle Ψ deviating from 0°, for example an angle Ψ of approx. 45°. The angles η, ζ, ε between the main extension directions 7H of respectively two adjacent guiding elements 7 of a row RN of tubular elements 2 may be chosen to be of different sizes. Moreover the angles η, ζ, ε in different rows RN of tubular elements 2 may be chosen to be of different sizes. The different angles η, ζ, ε allow the dynamic pressure/the heat transition between the first fluid F1 and the second fluid F2 to be varied.
(34) FIG. 11B also shows a collection vessel 4 and its collection baseplate 4C or a distribution vessel 5 and its distribution baseplate 5C, which are essentially curved, wherein two rectangular end regions are connected to each other via a circular-segment-shaped region when viewed in a virtual cutting plate E essentially at right angles to the longitudinal axes L of tubular elements 2. The directions indicated by arrows of the second fluid F2 on entry into the flow channel 3 and on exit from the flow channel 3 enclose an angle Ψ of approx. 90°. Here again the angles η, ζ, ε between the main extension directions 7H of respectively two adjacent guiding elements 7 of a row RN of tubular elements 2 may be chosen to be of different sizes.
