FR3158150A1 - Corrugated spacer for heat exchanger - Google Patents

Abstract

The invention relates to a corrugated interlayer (10) for an exchanger (1), comprising: - a first section (11), comprising first flat walls (21), connected two by two by first peaks (31) to form undulations, each of the first peaks (31) comprising a first flat portion (310), - a second section (12), comprising second flat walls (22), connected two by two by second peaks (32) to form undulations, each of the second peaks (32) consisting of 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 two by two by third peaks (33) to form undulations, said third peaks (33) being configured to gradually change from the shape of the first peak (31) to the shape of the second vertex (32). Abstract figure: Figure 1

Description

Corrugated spacer for heat exchanger

The invention relates to the field of heat exchangers, in particular for motor vehicles.

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

The spacers are formed by corrugated strips winding between two opposite tube walls, each of the peaks of said corrugations being in contact, in particular brazed, with one of said walls. Between two peaks, the spacers are pierced with louvers, said louvers making it possible to improve heat transfer.

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 feed manifold. These thermal stresses notably result in the deterioration of the spacers inside the tubes.

In particular, thermal and mechanical stresses, also known as thermal shock, cause the interlayers to expand. This expansion causes the interlayers to deteriorate, or buckle.

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

To this end, the present invention provides a corrugated interlayer for a heat exchanger. Said corrugated interlayer comprises:
- a first section, comprising a set of first flat walls, connected two by two by first peaks to form undulations, each of the first peaks comprising a first flat portion,
- a second section, comprising a set of second flat walls, connected two by two by second peaks to form undulations, each of the second peaks being made up of a rounded portion,
- a third section, called a transition section, inserted between the first section and the second section, said third section comprising a set of third flat walls, connected two by two by third vertices to form undulations, said third vertices being configured to pass from the shape of the first vertex, comprising the first flat portion, to the shape of the second vertex, consisting of the rounded portion.

The first section forms roughly notched corrugations. Notched corrugations help limit the pressure losses generated by the spacers while limiting the impact on heat exchange.

The first notched section offers better resistance to mechanical and thermal stresses.

Each of the first, second and third vertices extends in a direction, called the direction of elongation of the intercalaries, perpendicular to the direction of the oscillations.

The first, third and second sections follow one another along the direction of elongation of the interlayers.

The undulations of the interlayers are included between a first plane and a second plane.

Each of the first plane portions extends along one of the first or second planes.

Each of the rounded portions includes a ridge, each of the ridges extending along one of the first or second planes.

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

According to an exemplary 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.

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.

Each of the third vertices includes a second planar portion, extending from the first planar portion of the first vertex towards the rounded portion of the second vertex.

Each of the second planar portions has a triangle shape. A first side of said triangle is located at the junction between the first section and the third section. Said first side matches the shape of the first planar portion. A first point of said triangle is located at the junction between the second section and the third section. Said first point is positioned in the extension of the crest of the second vertex.

Each of the second plane portions extends along one of the first or second planes.

According to an exemplary 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 discontinuously.

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.

According to an exemplary embodiment of the invention, the interlayer is a single piece. In particular, the first, second and third sections are of continuous material.

A single-piece spacer helps limit manufacturing process costs. From a manufacturing process perspective, a single-piece spacer requires a single assembly operation, saving time compared to assembling multiple separate sections.

According to an exemplary embodiment of the invention, the spacer is made of aluminum.

According to an exemplary embodiment of the invention, the first flat walls are parallel to each other, in particular the first flat walls are perpendicular to the first flat portions.

According to an exemplary embodiment of the invention, each of the flat portions is connected to the flat walls by folds.

According to an exemplary embodiment of the invention, the second flat walls are parallel to each other.

According to an exemplary embodiment of the invention, at least one of the first and/or second and/or third flat walls comprises a plurality of shutters, said shutters being produced by cutting and forming said first and/or second and/or third wall.

The shutters generate turbulence and improve heat transfer.

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

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

According to an exemplary embodiment of the invention, the corrugated spacers are fixed to the heat exchanger tubes by brazing.

According to an exemplary embodiment of the invention, the first section of each of the spacers is positioned at one of the ends of each of the tubes of the heat exchanger.

Other features, details and advantages will become apparent upon reading the detailed description below, and upon analyzing the attached drawings, in which:

FIG. 1 is a perspective view of a heat exchanger comprising an interlayer according to the invention.

FIG. 2 is a perspective view of the interlayer of the FIG. 1 .

FIG. 3 is a sectional view of the first and second sections of the interlayer of the FIG. 1 .

FIG. 4 is a partial perspective view of the interlayer of the FIG. 1 centered on the third section of the interleaf.

FIG. 5 is a sectional view of a tube including the interlayer of the FIG. 1 .

To facilitate reading the figures, the different elements are not necessarily represented to scale. In these figures, identical elements bear the same references. Some elements or parameters may be indexed, i.e. designated for example by first element or second element, or first parameter and second parameter, etc. This indexing is intended to differentiate similar, but not identical, elements or parameters. This indexing does not imply a priority of one element or parameter over another. The names 'first', 'second', 'third', etc. can thus be interchanged.

The invention relates to an interlayer 10 for a heat exchanger 1, in particular an exchanger for cooling the charge air for a heat engine, such as a diesel engine of a motor vehicle. Such a heat exchanger 1 is shown FIG. 1 . Such a heat exchanger 1 may be a so-called “air-liquid” exchanger, that is to say an exchanger in which the fluids which exchange heat are air and a liquid such as water, or an “air-air” exchanger, that is to say an exchanger in which the two fluids which exchange heat are air. Of course, the invention is not limited to motor vehicle charge air coolers and may be applied to other types of heat exchangers.

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

As depicted 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.

The first section 11 comprises a set of first flat walls 21, connected two by two by first peaks 31 to form undulations, each of the first peaks 31 comprising a first flat portion 310.

The second section 12 comprises a set of second flat walls 22, connected two by two by second peaks 32 to form undulations, each of the second peaks 32 consisting of a rounded portion 320.

The third section 13, called the transition section, is interposed between the first section 11 and the second section 12. Said third section 13 comprises a set of third flat walls 23, connected two by two by third vertices 33 to form undulations, said third vertices 33 being configured to pass 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.

The undulations of the spacers 10 are between a first plane P1 and a second plane P2.

Each of the first planar portions 310 extends along one of the first or second planes P1, P2.

Each of the rounded portions 320 comprises a ridge 321, each of the ridges 321 extends along one of the first or second planes P1, P2.

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 continuously.

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.

As depicted 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.

As shown FIG. 4 , each of the second planar portions 330 has a triangle 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 matches 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 the extension of the crest 321 of the second vertex 32.

Each of the second planar portions 330 extends along one of the first or second planes P1, P2.

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 discontinuously.

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.

The first section 11 forms substantially notched undulations. Notched undulations make it possible to limit the pressure losses generated by the spacers 10 while limiting the impact on heat exchanges.

The first section 11 in notched form offers better resistance to mechanical and thermal stresses.

Each of the first, second and third vertices 31, 32, 33 extends in a direction X, called the direction of elongation of the spacers 10. The direction X is perpendicular to the direction of the oscillations Y.

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

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

According to the embodiment shown in figures 2, 4 and 5, the corrugated interlayer is in one piece.

A single-piece 10-section spacer helps limit manufacturing process costs. From a manufacturing process perspective, a single-piece 10-section spacer requires a single assembly operation, saving time compared to assembling multiple separate sections.

As depicted 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.

In the same way, as represented FIG. 3 , according to a particular embodiment, the second flat walls 22 are parallel to each other.

As represented, 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 shutters 40, said shutters 40 being produced by cutting and forming 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.

The 40 louvers generate turbulence and improve heat transfer.

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

As shown in 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.

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 (10)

Corrugated spacer (10) for heat exchanger (1), comprising:
- a first section (11), comprising a set of first flat walls (21), connected two by two by first peaks (31) to form undulations, each of the first peaks (31) comprising a first flat portion (310),
- a second section (12), comprising a set of second flat walls (22), connected two by two by second peaks (32) to form undulations, each of the second peaks (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 two by two by third vertices (33) to form undulations, said third vertices (33) being configured to pass 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). Corrugated insert (10) according to the preceding claim, in which 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. A corrugated interlayer (10) according to any preceding claim, wherein the corrugated interlayer (10) is in one piece. Corrugated insert (10) according to any one of the preceding claims, wherein the first planar walls (21) are parallel to each other, in particular the first planar walls are perpendicular to the first planar portions (310). Corrugated interlayer (10) according to any one of the preceding claims, wherein each of the planar portions (310) is connected to the planar walls by folds (311). A corrugated spacer (10) according to any preceding claim, wherein the second planar walls (22) are parallel to each other. Corrugated spacer (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 produced by cutting and forming said first and/or second and/or third wall (21, 22, 23). Corrugated insert (10), according to any one of the preceding claims, in which the first section (11) extends, in a direction (X) of elongation of the insert (10), over a length of less than 10 mm, in particular less than 5 mm. 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). Heat exchanger (1) according to the preceding claim, wherein the first section (11) of each of the spacers (10) is positioned at one of the ends of each of the tubes (2).