Corrugated spacer for heat exchanger

Abstract

The invention relates to a corrugated interlayer (10) for a heat exchanger (1), comprising: - a first section (11), comprising first flat walls (21), connected in pairs by first vertices (31) to form corrugations, each of the first vertices (31) comprising a first flat portion (310), - a second section (12), comprising second flat walls (22), connected in pairs by second vertices (32) to form corrugations, each of the second vertices (32) being constituted by a rounded portion (320), - a third section (13) interposed between the first section (11) and the second section (12), said third section (13) comprising third flat walls (23), connected in pairs by third vertices (33) to form corrugations, said third vertices (33) being configured to gradually transition from the shape of the first vertex (31) to the shape of the second summit (32). Figure of the summary: Figure 1

Description

Title of the invention: Corrugated interlayer for heat exchanger technical field

[0001] The invention relates to the field of heat exchangers, particularly for motor vehicles. Previous technique

[0002] In known heat exchangers, for example those used in the automotive industry, heat exchange can take place between two fluids. These heat exchangers comprise a bundle of tubes connected at their ends by two manifolds. Interlayers can be placed between the tubes and / or within the tubes of the tube bundle so as to increase the heat exchange between the first fluid circulating in the tubes and the second fluid circulating around the tubes.

[0003] The spacers are formed by corrugated strips winding between two opposing tube walls, each crest of said corrugations being in contact, in particular brazed, with one of said walls. Between two crests, the spacers are pierced with louvers, said louvers allowing for improved heat transfer.

[0004] During operation, the first and second fluids circulate at different temperatures. The temperature difference between the two fluids generates significant thermal and mechanical stresses, particularly at the junction between the tubes and the heat exchanger's feed manifold. These thermal stresses notably result in the deterioration of the spacers inside the tubes.

[0005] In particular, thermal and mechanical stresses, also known as thermal shock, cause the interlayers to expand. This expansion leads to deterioration of the interlayers, or buckling.

[0006] The objective of the invention is therefore to locally improve the resistance of the interlayers, without significantly impacting the ratio between heat transfers and pressure losses, and while limiting the impact on the manufacturing process of the heat exchanger. Summary

[0007] To this end, the present invention proposes a corrugated interlayer for a heat exchanger. Said corrugated interlayer comprises: - a first section, comprising a set of initial flat walls, connected in pairs by initial vertices to form undulations, each of the initial vertices comprising an initial flat portion, - a second section, comprising a set of second flat walls, connected paired by second vertices to form undulations, each of the second vertices being made up of a rounded portion, - a third section, called transition, inserted between the first section and the second section, said third section comprising a set of third flat walls, connected in pairs by third vertices to form undulations, said third vertices being configured to go from the shape of the first vertex, comprising the first flat portion, to the shape of the second vertex, consisting of the rounded portion.

[0008] The first section forms roughly crenellated undulations. Crenellated undulations help to limit the pressure losses generated by the interlayers while limiting the impact on heat exchange.

[0009] The first angled section offers better resistance to mechanical and thermal stresses.

[0010] Each of the first, second and third vertices extends along a direction, called the direction of elongation of the intercalaries, perpendicular to the direction of the oscillations.

[0011] The first, third and second sections follow one another along the direction of elongation of the intercalaries.

[0012] The undulations of the intercalaries are contained between a first plane and a second plane.

[0013] Each of the first flat portions extends along one of the first or second planes.

[0014] Each of the rounded portions includes a ridge, each of the ridges extends along one of the first or second planes.

[0015] The third section is in contact with the first section and with the second section.

[0016] According to an example of an embodiment of the invention, the transition from the shape of the first vertex, comprising the first flat portion, to the shape of the second vertex, consisting of the rounded portion, of the third vertices is done continuously.

[0017] In other words, the shape of the third vertex gradually changes from the shape of the first vertex, comprising the first flat portion, to the shape of the second vertex, consisting of the rounded portion.

[0018] Each of the third vertices includes a second flat portion, extending from the first flat portion of the first vertex towards the rounded portion of the second vertex.

[0019] Each of the second planar portions has a triangular shape. A first side of said triangle is located at the junction between the first section and the third section. Said first side follows the shape of the first planar portion. A first The apex of said triangle is located at the junction between the second section and the third section. Said first apex is positioned in line with the ridge of the second vertex.

[0020] Each of the second flat portions extends along one of the first or second planes.

[0021] According to an example of an embodiment of the invention, the transition from the shape of the first vertex, comprising the first flat portion, to the shape of the second vertex, consisting of the rounded portion, of the third vertices is done in a discontinuous manner.

[0022] In other words, the shape of the third vertex passes, in stages, from the shape of the first vertex, comprising the first flat portion, to the shape of the second vertex, consisting of the rounded portion.

[0023] According to one embodiment of the invention, the interlayer is a single piece. In particular, the first, second and third sections are of continuous material.

[0024] A one-piece spacer helps to limit manufacturing process costs. Indeed, from a manufacturing process perspective, a one-piece spacer requires only one assembly operation, which represents a time saving compared to assembling several isolated sections.

[0025] According to one embodiment of the invention, the spacer is made of aluminium.

[0026] According to one embodiment of the invention, the first flat walls are pa parallels to each other, in particular the first flat walls are perpendicular to the first flat portions.

[0027] According to one embodiment of the invention, each of the flat portions is connected to the flat walls by folds.

[0028] According to one embodiment of the invention, the second flat walls are parallel to each other.

[0029] According to an example of an embodiment of the invention, at least one of the first and / or second and / or third flat walls comprises a plurality of louvers, said louvers being made by cutting and forming said first and / or second and / or third wall.

[0030] The louvers generate turbulence and improve heat transfer.

[0031] According to an example of an embodiment of the invention, the first section extends, along the direction of elongation of the interlayer, over a length of less than 10 mm, in particular less than 5 mm.

[0032] The invention also relates to a heat exchanger comprising a bundle of parallel tubes and comprising a multiplicity of corrugated interlayers, said corrugated interlayers being arranged in the tubes of the bundle and fixed to the tubes by their respective first, second and third vertices.

[0033] According to one embodiment of the invention, the corrugated spacers are fixed to the heat exchanger tubes by brazing.

[0034] According to an embodiment of the invention, the first section of each of the spacers is positioned at one end of each of the heat exchanger tubes. Brief description of the drawings

[0035] Other features, details and advantages will become apparent upon reading the detailed description below, and upon analysis of the accompanying drawings, on which:

[0036] [Fig-1] is a perspective view of a heat exchanger comprising an interlayer according to the invention.

[0037] [Fig.2] is a perspective view of the insert of [Fig.1].

[0038] [Fig.3] is a cross-sectional view of the first and second sections of the interlayer of the [Fig.l].

[0039] [Fig.4] is a partial perspective view of the insert of [Fig.1] centered on the third section of the interleaf.

[0040] [Fig.5] is a cross-sectional view of a tube including the interlayer of [Fig.1]. Description of the implementation methods

[0041] To facilitate reading the figures, the different elements are not necessarily drawn to scale. In these figures, identical elements bear the same reference numerals. Certain elements or parameters may be indexed, that is, designated, for example, as first element or second element, or first parameter and second parameter, etc. This indexing aims to differentiate similar, but not identical, elements or parameters. This indexing does not imply a priority of one element or parameter over another. The designations 'first', 'second', 'third', etc., can thus be interchanged.

[0042] The invention relates to an interlayer 10 for a heat exchanger 1, in particular a heat exchanger for cooling the charge air of an internal combustion engine, such as a diesel engine in a motor vehicle. Such a heat exchanger 1 is shown [Fig. 1]. Such a heat exchanger 1 can be an "air-liquid" exchanger, that is, an exchanger in which the fluids exchanging heat are air and a liquid such as water, or an "air-air" exchanger, that is, an exchanger in which both fluids exchanging heat are air. Of course, the invention is not limited to charge air coolers for motor vehicles and can be applied to other types of heat exchangers.

[0043] The heat exchanger 1 shown in [Fig. 1] comprises a heat exchange bundle which, in the example, is formed by a bundle of tubes 2. Each of the tubes 2 in the tube bundle 2 comprises a corrugated spacer 10, inserted into said tube 2. The role of the corrugated spacer 10 is to promote heat exchange, on the one hand by forming an additional exchange surface, on the other hand by creating turbulence.

[0044] As shown [Fig.2], a corrugated interlayer 10 for a heat exchanger 1 comprises a first section 11, a second section 12 and a third section 13.

[0045] The first section 11 comprises a set of first flat walls 21, connected in pairs by first vertices 31 to form undulations, each of the first vertices 31 comprising a first flat portion 310.

[0046] The second section 12 comprises a set of second flat walls 22, connected in pairs by second vertices 32 to form undulations, each of the second vertices 32 being made up of a rounded portion 320.

[0047] The third section 13, called the transition section, is inserted between the first section 11 and the second section 12. Said third section 13 comprises a set of third flat walls 23, connected in pairs by third vertices 33 to form undulations, said third vertices 33 being configured to go from the shape of the first vertex 31, comprising the first flat portion 310, to the shape of the second vertex 32, consisting of the rounded portion 320.

[0048] The undulations of the intercalated 10 are contained between a first plane PI and a second plane P2.

[0049] Each of the first planar portions 310 extends along one of the first or second planes PI, P2.

[0050] Each of the rounded portions 320 includes a ridge 321, each of the ridges 321 extends along one of the first or second planes PI, P2.

[0051] According to the embodiment illustrated, in particular, [Fig.4], the transition from the shape of the first vertex 31, comprising the first flat portion 310, to the shape of the second vertex 32, consisting of the rounded portion 320, of the third vertices 33 is done in a continuous manner.

[0052] In other words, the shape of the third vertex 33 gradually changes from the shape of the first vertex 31, comprising the first flat portion 310, to the shape of the second vertex 32, consisting of the rounded portion 320.

[0053] As shown [Fig.4], each of the third vertices 330 comprises a second planar portion 330, extending from the first planar portion 310 of the first vertex 31 towards the rounded portion 320 of the second vertex 32.

[0054] As illustrated [Fig. 4], each of the second planar portions 330 has a triangular shape. A first side of said triangle is located at the junction between the first section 11 and the third section 13. Said first side follows the shape of the first planar portion 310. A first point of said triangle is located at the junction between the second section 12 and the third section 13. Said first point is positioned in line with the ridge 321 of the second vertex 32.

[0055] Each of the second planar portions 330 extends along one of the first or second planes PI, P2.

[0056] According to an alternative embodiment of the invention, not illustrated, the transition from the shape of the first vertex 31, comprising the first flat portion 310, to the shape of the second vertex 32, consisting of the rounded portion 320, of the third vertices 33 is done in a discontinuous manner.

[0057] In other words, the shape of the third vertex 33 passes, in stages, from the shape of the first vertex 31, comprising the first flat portion 310, to the shape of the second vertex 32, consisting of the rounded portion 320.

[0058] The first section 11 forms roughly crenellated undulations. Crenellated undulations help to limit the pressure losses generated by the interlayers 10 while limiting the impact on heat exchange.

[0059] The first crenellated section 11 offers better resistance to mechanical and thermal stresses.

[0060] Each of the first, second and third vertices 31, 32, 33 extends along a direction X, called the direction of elongation of the intercalaries 10. The direction X is perpendicular to the direction of the oscillations Y.

[0061] The first, third and second sections 11, 13, 12 follow one another along the direction of elongation of the intercalaries 10.

[0062] The third section 13 is in contact with the first section 11 and with the second section 12.

[0063] According to the embodiment shown in figures 2, 4 and 5, the corrugated interlayer is a single piece.

[0064] A one-piece spacer 10 helps to limit manufacturing process costs. Indeed, from a manufacturing process perspective, a one-piece spacer 10 involves only one assembly operation, and therefore a time saving compared to assembling several isolated sections.

[0065] As shown [Fig.3], according to a particular embodiment, the first flat walls 21 are parallel to each other, in particular the first flat walls 21 are perpendicular to the first flat portions 310. Each of the flat portions 310 is connected to the flat walls by folds 311.

[0066] Similarly, as shown [Fig.3], according to a particular embodiment, the second flat walls 22 are parallel to each other.

[0067] As shown, in particular [Fig. 2], at least one of the first and / or second and / or third flat walls 21, 22, 23 comprises a plurality of louvers 40, said louvers 40 being formed by cutting and shaping said first and / or second and / or third wall 21, 22, 23. In particular, according to the embodiment shown [Fig. 2], the second walls 22 comprise a plurality of shutters 40.

[0068] The louvers 40 generate turbulence and improve heat transfer.

[0069] The first section 11 extends, along the X direction of elongation of the interlayer 10, over a length of less than 10 mm, in particular less than 5 mm.

[0070] As shown in cross-section, [Fig.5], each of the corrugated spacers 10 is arranged in the tubes 2 of the bundle and fixed to the tubes 2 by their respective first, second and third vertices 31, 32, 33. According to a particular embodiment, the corrugated spacers 10 are fixed to the tubes 2 by brazing.

[0071] According to the embodiment shown [Fig.5], the first section 11 of each of the spacers 10 is positioned at one of the ends of each of the tubes 2.

Claims

Demands

1. Corrugated interlayer (10) for a heat exchanger (1), comprising: - a first section (11), comprising a set of first flat walls (21), connected in pairs by first vertices (31) to form corrugations, each of the first vertices (31) comprising a first flat portion (310), - a second section (12), comprising a set of second flat walls (22), connected in pairs by second vertices (32) to form corrugations, each of the second vertices (32) being made up of a rounded portion (320), - a third section (13), called a transition section, interposed between the first section (11) and the second section (12), said third section (13) comprising a set of third flat walls (23), connected in pairs by third vertices (33) to form corrugations, said third vertices (33) being configured to transition from the shape of the first vertex (31),comprising the first flat portion (310), in the shape of the second vertex (32), consisting of the rounded portion (320).

2. Corrugated interlayer (10) according to the preceding claim, wherein the transition from the shape of the first vertex (31), comprising the first flat portion (310), to the shape of the second vertex (32), consisting of the rounded portion (320), of the third vertices (33) is done continuously.

3. Corrugated interlayer (10) according to any one of the preceding claims, wherein the corrugated interlayer (10) is monobloc.

4. Corrugated interlayer (10) according to any one of the preceding claims, wherein the first flat walls (21) are parallel to each other, in particular the first flat walls are perpendicular to the first flat portions (310).

5. Corrugated interlayer (10) according to any one of the preceding claims, wherein each of the flat portions (310) is connected to the flat walls by folds (311).

6. Corrugated interlayer (10) according to any one of the preceding claims, wherein the second flat walls (22) are parallel to each other.

7. Corrugated interlayer (10) according to any one of the preceding claims, wherein at least one of the first and / or second and / or third flat walls (21, 22, 23) comprises a plurality of louvers (40), said louvers (40) being made by cutting and shaping said first and / or second and / or third wall (21, 22, 23).

8. Corrugated interlayer (10), according to any one of the preceding claims, wherein the first section (11) extends, along an elongation direction (X) of the interlayer (10), over a length of less than 10 mm, in particular less than 5 mm.

9. Heat exchanger (1) comprising a bundle of parallel tubes (2) and comprising a multiplicity of corrugated spacers (10) according to any one of the preceding claims, said corrugated spacers (10) being arranged in the tubes (2) of the bundle and fixed to the tubes (2) by their respective first, second and third vertices (31, 32, 33).

10. Heat exchanger (1) according to the preceding claim, wherein the first section (11) of each of the spacers (10) is positioned at one end of each of the tubes (2).

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