FR3088110A1 - Heat exchanger between at least a first fluid and a second fluid and corresponding heat exchange method - Google Patents

Abstract

Heat exchanger (1) between at least a first fluid and a second fluid, comprising: an assembly (21) of fluid circulation channels each extending in a longitudinal direction; and distribution means (3, 4) for distributing the first fluid exclusively in first circulation channels of the assembly and for distributing the second fluid exclusively in second circulation channels of the assembly, at least one first channel being disposed between two second channels along a first axis, said first channel being further disposed between two other second channels along a second axis, at least three of the set of said two second channels and said second other channels being among the closest channels of said first channel.

Description

Heat exchanger between at least a first fluid and a second fluid and corresponding heat exchange method.

The present invention relates to the field of heat exchangers. A heat exchanger is a device for transferring thermal energy from one fluid to another.

The present invention relates more specifically to a heat exchanger between at least a first fluid and a second fluid, comprising:

at least one set of fluid circulation channels each extending in a longitudinal direction; and distribution and collection means, adapted to distribute the first fluid and the second fluid in the channels of at least said assembly, the distribution and collection means being adapted to distribute the first fluid exclusively in first circulation channels of the 'together and to distribute the second fluid exclusively in second circulation channels of the assembly.

Such a heat exchanger is for example described in FR 3 023 494, in which only one fluid circulates per stratum.

The manufacturing principle is a stack of grooves of grooved plates to create channels. The assembly and sealing between plates is by diffusion welding.

It is desirable to manage to improve the heat exchange between two fluids in the heat exchangers, while respecting as much as possible the constraints linked to the size and the mass of the exchanger, to the manufacturing complexity, to the fouling of channels. It is also important to guarantee resistance to internal pressure and to limit pressure losses. The heat exchange is improved compared to the prior art by increasing the surface of the faces of the channels of the first fluid which are in contact with the faces of the channels of the second fluid

To this end, according to a first aspect, the invention provides a heat exchanger between at least a first fluid and a second fluid of the aforementioned type, characterized in that at least a first channel is disposed between two second channels along a first axis, said first channel being further disposed between two other second channels along a second axis, at least three of all of said two second channels and said second other channels being part of the channels closest to said first channel.

The invention thus makes it possible to increase the thermal performance in a heat exchanger while allowing a space and a reduced mass.

In embodiments, the heat exchanger according to the invention further comprises one or more of the following characteristics:

the channels are arranged in the form of a matrix in a plane perpendicular to the longitudinal direction, the rows, respectively columns of the matrix being respectively parallel to the first, respectively second axis, and the first channels being arranged in said plane alternately with the second channels along said first and second axes;

- The section of the channels in said plane perpendicular to the longitudinal direction of the channels is square;

- The distribution and collection means are adapted to distribute in a direction the first fluid in the first channels of the assembly and to distribute in an opposite direction the second fluid in the second channels of the assembly;

the heat exchanger comprises at least said set of fluid circulation channels and another set of fluid circulation channels arranged parallel similar to said assembly and the distribution and collection means are suitable:

- to distribute the first fluid and the second fluid in the channels of said assembly,

- to collect the first fluid and the second fluid when they leave said assembly,

- to distribute, in the other assembly and in a direction opposite to the direction of distribution of the first fluid in the assembly, the first fluid collected,

- to distribute, in the other assembly and in a direction opposite to the direction of distribution of the second fluid in the assembly, the second fluid collected;

the distribution and collection means comprise at least one channel box comprising:

first canister circulation channels of the first fluid connected to the first canals of the channel set and to the first canals of the other set of channels and second canister channels of the second fluid, wherein each second canister channel extends at one of its ends into a second channel of the set of channels and at another of its ends into a second channel of the other set of channels, the second channel rotating in the transverse plane in its portion between said ends and the cross section of the second channel being further reduced in size in said portion, the first channels comprising spaces thus formed between said second channels by said rotation, reduction in size. According to a second aspect, the present invention provides a method of heat exchange in a heat exchanger between at least a first fluid and a second fluid, comprising:

at least one set of fluid circulation channels each extending in a longitudinal direction; and distribution and collection means, adapted to distribute the first fluid and the second fluid in the channels of at least said assembly;

at least a first channel is disposed between two second channels along a first axis, said first channel being further disposed between two other second channels along a second axis, at least three of the set of said two second channels and said second other channels forming part of the channels closest to said first channel.

the method being characterized in that it comprises the following stages:

distribution, by means of distribution and collection, of the first fluid exclusively in first circulation channels of the assembly and of the second fluid exclusively in second circulation channels of the assembly.

In embodiments, the heat exchange method according to the invention further comprises one or more of the following characteristics:

the channels are arranged in the form of a matrix in a plane perpendicular to the longitudinal direction, the rows, respectively columns of the matrix being respectively parallel to the first, respectively second axis, and the first channels being arranged in said plane alternately with the second channels along said first and second axes;

- The section of the channels in said plane perpendicular to the longitudinal direction of the channels is square;

the distribution and collection means distribute in a direction the first fluid in the first channels of the assembly and distribute in an opposite direction the second fluid in the second channels of the assembly.

These characteristics and advantages of the invention will appear on reading the description which follows, given solely by way of example, and made with reference to the accompanying drawings, in which;

FIG. 1 represents a perspective view of a heat exchanger in an embodiment of the invention;

Figure 2 is a cross-sectional view of the exchanger of Figure 1 in one embodiment of the invention; Figure 3 is an embodiment view of the invention;

Figure 4 is an embodiment view of the invention;

Figure 5 is an embodiment view of the invention;

Figure 6 is an embodiment view of the invention.

in in in section cut section cut from du du du block block block block end block end end end in in in in a one mode mode mode de de de de

FIG. 1 represents a perspective view of a heat exchanger 1 between two fluids named one, “fluid f _a ”, and the other, “fluid f _b ”, in an embodiment of the invention. The fluids f _a and f _b are liquid or gaseous. They are not mixed in the exchanger.

In the embodiment considered, the exchanger 1 comprises an intermediate block of channels 2, and two end blocks 3 and 4, located on either side of the intermediate block of channels 2.

Blocks 3 and 4 are suitable for distributing and collecting fluids fa and f _b .

The block 3 is on the one hand connected to the conduit 5 for inlet of the fluid f _a into the exchanger 1. The block 3 is on the other hand connected to the conduit 6 for the outlet of the fluid f _a , by which the fluid f _a leaves block 3 once processed.

With reference to FIG. 2 which is a cross-sectional view, along the line AA, of the intermediate block of channels 2, the latter comprises 6 sets of channels (also called “passes”) 21, 22, 23, 24, 25, 26 arranged in a matrix of 2 rows and 3 columns. The sets of channels 21, 22, 23 are arranged successively along the X axis. The sets of channels 24, 25, 26 are also successively arranged along the X axis of an orthonormal reference (X, Y, Z), under the respective channel assemblies 23, 22, 21, as shown in FIG. 2.

Each channel assembly 21, 22, 23, 24, 25, 26 comprises 24 channels, referenced 11. Each channel 11 extends along the Y axis, between the end blocks 3 and 4. Each channel 11 is of square section in the transverse plane (ie the plane (X, Z)) and is adapted to the circulation of fluid from one end of the channel to the other, under the effect of the pressure prevailing in the exchanger 2.

The channels 11 of each set 21, 22, 23, 24, 25, 26 are, in the embodiment considered with reference to the figures, arranged in a matrix of 6 rows and 4 columns in the plane (X, Z) as shown in Figure 2. Each channel 11 thus has 4 side walls extending along the Y axis.

The end blocks 3 and 4 are adapted to implement the process steps indicated below.

Thus the end blocks 3 and 4 are adapted to distribute the fluid f _a exclusively at the inlet of certain channels of the intermediate block 2 (and to collect the fluid f _a leaving these channels) and to distribute the fluid f _b exclusively at the inlet other channels of the intermediate block 2 (and to collect the fluid f _b at the outlet of these channels), so that each longitudinal wall of at least one circulation channel 11 of the fluid f _has faced a longitudinal wall of a fluid circulation channel f _b .

In the embodiment considered, the end blocks 3 and 4 are adapted to distribute (and similarly collect) the fluids f _a and f _b alternately in the channels along the X axis and along the axis Z, both at the level of each set 21 to 26 and considering the global matrix 12 * 12 of the channels 11 of the intermediate block 2.

In Figure 2, the fluid circulation channels f _b are shown in dotted lines and the fluid circulation channels f _a are shown in solid lines.

Thus a fluid circulation channel f _a has for direct neighbors located on either side of it along the axis X, two fluid circulation channels f _b (or a single fluid circulation channel f _b for the channels fluid circulation f _a located at the edge of the intermediate block 2 and having only a neighboring channel along the axis X). And a fluid circulation channel f _a thus has for direct neighbors situated on either side of it along the axis Z, two fluid circulation channels f _b (or a single fluid circulation channel f _b for the fluid circulation channels f _a located at the edge of the intermediate block 2 and having only one neighbor along the axis Z).

Similarly, a fluid circulation channel f _b thus has direct neighbors located on either side of it along the axis X, two fluid circulation channels f _a (or a single fluid circulation channel f _a for the fluid circulation channels f _a located at the edge of the intermediate block 2 and having only a neighboring channel along the axis X). And a fluid circulation channel f _b thus has for direct neighbors situated on either side of it along the axis Z, two fluid circulation channels f _a (or a single fluid circulation channel f _a for the fluid circulation channels f _a located at the edge of the intermediate block 2 and having only one neighbor along the axis Z).

The invention thus makes it possible to increase the heat exchange while ensuring high reliability of the exchanger.

The direction of circulation along the Y axis of the fluids as distributed by the end blocks 3 and 4 in the channels of the intermediate block 2 in the embodiment considered, is indicated in FIG. 2 and the following figures , by arrows in dotted lines for the fluid f _b and in solid lines for the fluid f _a .

Thus, in the embodiment considered, the end block 3 is adapted to receive the fluid f _a coming from the inlet duct 5 and to supply the fluid f _a at the inlet of the fluid circulation channels f _a (indicated in lines full in Figure 2) of the assembly 21 in the direction indicated by the arrow in solid lines.

The end block 3 is further adapted to collect the fluid f _a at the outlet from the channels for circulation of the fluid f _a (indicated in solid lines in FIG. 2) from the assembly 22 and to then supply it at the inlet of the channels. of circulation of the fluid f _a (indicated in solid lines in FIG. 2) of the assembly 23 in the direction indicated by the arrow in solid line.

The end block 3 is further adapted to collect the fluid f _a at the outlet from the channels for circulation of the fluid f _a (indicated in solid lines in FIG. 2) from the assembly 24 and to then supply it at the inlet of the channels. of circulation of the fluid f _a (indicated in solid lines in FIG. 2) of the assembly 25 in the direction indicated by the arrow in solid line.

The end block 3 is further adapted to collect the fluid f _a at the outlet from the fluid circulation channels f _a (indicated in solid lines in FIG. 2) of the assembly 26 and to then supply it at the inlet of the duct. output 6.

Similarly, in the embodiment considered, the end block 3 is adapted to collect the fluid f _b at the outlet from the circulation channels of the fluid f _b (indicated by dotted lines in FIG. 2) of the assembly 21 and for then supply it at the input of the fluid circulation channels f _b of the assembly 22 in the direction indicated by the arrow in dotted lines.

The end block 3 is further adapted to collect the fluid f _b at the outlet of the fluid circulation channels f _b of the assembly 23 and to then supply it at the inlet of the fluid circulation channels f _b of the assembly 24 in the direction indicated by the arrow in dotted lines.

The end block 3 is further adapted to collect the fluid f _b at the outlet of the fluid circulation channels f _b of the assembly 25 and to then supply it at the inlet of the fluid circulation channels f _b (indicated in dotted lines) in FIG. 2) of the assembly 26.

Similarly, in the embodiment considered, the end block 4 is adapted to receive the fluid f _b (coming from the inlet block 7 at the inlet of the fluid circulation channels f _b (indicated by dotted lines in the figure 2) of the assembly 21 in the direction indicated by the arrow in dotted lines.

The end unit 4 is further adapted to collect the fluid f _b at the outlet flow channels of the fluid f _b of the assembly 22 and to provide the next entry in flow channels of the fluid f _b of all 23.

The end block 4 is further adapted to collect the fluid f _b at the outlet of the fluid circulation channels f _b of the assembly 24 and to then supply it at the inlet of the fluid circulation channels f _b of the assembly 25.

The end block 4 is further adapted to collect the fluid f _b at the outlet of the fluid circulation channels f _b of the assembly 26 and to then supply it at the inlet of the outlet block 8.

Similarly, in the embodiment considered, the end block 4 is adapted to collect the fluid f _a at the outlet from the channels for circulation of the fluid f _a (indicated in solid lines in FIG. 2) of the assembly 21 and for then supply it at the input of the fluid circulation channels f _a of the assembly 22 in the direction indicated by the arrow in solid lines.

The end block 4 is further adapted to collect the fluid f _a at the outlet of the fluid circulation channels f _a of the assembly 23 and to then supply it at the inlet of the fluid circulation channels f _a of the assembly 24.

The end block 4 is further adapted to collect the fluid f _a at the outlet from the fluid circulation channels f _a from the assembly 25 and to then supply it at the inlet to the fluid circulation channels f _a from the assembly 26.

Thus, the end blocks 3 and 4 are adapted to carry out the “U-turn” movements, also called “turning” movements with the fluids allowing them to make 6 passes in the intermediate block 2, passing successively through each assembly 21 to 26.

In one embodiment, the end blocks 3 and 4 have coiled channel boxes.

FIG. 3 is a view in the transverse plane (X, Z), of the box 31 with wound channels of the end block 3, in section at the level of the straight line BB shown in FIG. 2.

This box 31 (respectively the box 41) is suitable for making the turns of the fluid f _a in the end block 3 (respectively in the end block 4) between the sets of channels 22 and 23, between the sets 24 and 25, successively taken by the fluid f _a (respectively between the sets of channels 21 and 22, between the sets 23 and 24, and also between the sets 25 and 26 successively taken by the fluid f _a ).

As shown in Figure 3, the channel box 31 includes 6 sections 3 ₂ i, 3 ₂₂ , 3 ₂ 3, 3 ₂₄ , 3 _25> 3 ₂₆ arranged in a matrix of 2 rows and 3 columns, each section corresponding to the whole respective channels of the intermediate block facing it. It further comprises partitions between passes 50, 51, preventing the communication of fluids between the two sides of the partition: the fluid f _has left its channels is thus forced to make its U-turn between the passes included in the same area bounded by the partitions.

As a standard, the circles surrounding a point designate a fluid circulating towards the reader, in the case of this figure, ie along the axis Y, while the circles surrounding a cross designate a fluid circulating along the axis Y toward the sheet away from the reader. The arrows indicate directions of circulation of the fluid f _a in the plane of the section. The fluid circulation symbols relating to the fluid f _b are shown in dotted lines while the fluid circulation symbols relating to the fluid f _a are represented in solid lines. In order to let the fluid f _a circulate while the fluid f _b continues its path in its channels to make the turn further, within triangular boxes, the section of the channels of circulation of the fluid f _b is transformed within the box with rolled channels 31, passing from a square section (from the interface with the intermediate block 2) to a diamond section by, as the Y axis progresses, a rotation up to% of turn in the plane (X, Z) before gradually resuming a square section and returning arranged in an ordered matrix. In addition, the channels are offset and their section is locally reduced in size in order to create preferential horizontal and vertical passages (ie along the X and Z axes) for the other fluid. Thus, the bit rate in the different channels is the same.

In embodiments, a wound channel box according to the invention is produced without reduction in size of the channels and / or without offset.

The function can also be ensured by passing from the shape of the channels of the cross section (triangle, quadrilateral) to circular or ovoid channels in said portion. In this case, rotations are not necessary.

In one embodiment, each end block 3 and 4 further comprises boxes of triangular channels for making the turns of the fluid f _b at each end block. It will be noted that they are, in the embodiment considered, triangular, but that they can have other shapes in other embodiments, in particular shapes corresponding to other types of quadrilaterals.

More specifically, in the embodiment considered, each of the end blocks 3, 4 comprises two triangular boxes with horizontal turns (Le. To make the shift of the fluid f _b to pass from a set of channels to the neighboring set of channels along the X axis, ie between passes 21 and 22, between passes 22 and 23, between passes 24 and 25, then passes 25 and 26) and a triangular box with vertical turn (ie to make the turn fluid f _b to pass from a set of channels to the neighboring set of channels along the axis Z, ie between the passes 23 and 24).

Figure 4 is a sectional view of the end block 3 in the XY plane and along the line DD shown in Figure 1 showing these bend boxes.

The partitions between passes are referenced therein 60, 50.

The fluid f _b at the outlet of the pass 23 then having made a U-turn in the triangular box with vertical bend appearing to the left of the partition 60 in FIG. 4, then borrows the section 3 ₂ 4 before borrowing the pass 24.

The zone d corresponds to the horizontal triangular box where the fluid f _b makes a horizontal turn between the passes 25 and 26.

Figure 5 is a view in the transverse plane (X, Z) of the end block 4 showing the channel box wound in section at the line CC shown in Figure 1. Its operation is similar to that of the box with rolled channels described with reference to FIG. 3.

This box 41 is suitable for making the turns of the fluid f _a in the end block 4 between the sets of channels 21 and 22, between the sets 23 and 24, and also between the sets 25 and 26 successively taken up by the fluid f _a .

As shown in Figure 5, the channel box 41 includes 6 sections 4 ₂ i, 4 ₂₂ , 423, 4 ₂₄ 4 ₂₅ , 4 ₂₆ arranged in a matrix of 2 rows and 3 columns, each section corresponding to the respective set of channels of the intermediate block facing it. It also includes partitions between passes (in bold black lines).

FIG. 6 is a sectional view of the end block 4 in the XY plane at the level of the line DD represented in FIG. 1, showing more precisely the triangular turning boxes of the end block 4, and the path, represented in dotted lines, fluid f _b which turns around within these triangular boxes. In the case under consideration, unlike the triangular half-turn boxes of the end block 3 (triangle internal to the exchanger), in the end block 4, the shape of the triangle is "external" to the exchanger. This difference is due to the additive manufacturing method, in the case considered, of the exchanger.

In the present case, the fluid f _b comes from the pass 24, turns in the triangular box 10, then enters the pass 25. Not visible in FIG. 6, it makes a U-turn within the block of end 3 to enter the pass 26. Finally, the fluid f _b leaves the exchanger by the outlet 8.

In the embodiment considered, the height h of the exchanger 1 is for example 200 mm. And the length of one side of a channel 11 is for example 5 to 20 mm.

In one embodiment, the exchanger 1 was manufactured in a single piece, by additive manufacturing, for example in 316L stainless steel, or titanium etc., without requiring welding, assembly, or seals.

However, in other embodiments:

- The intermediate block 2 is manufactured by additive manufacturing or by extrusion and / or welding and / or machining; and or

- the end blocks 3 or 4 are manufactured by additive manufacturing or by extrusion or by machining, then assembled for example by welding with an intermediate block 2.

In the embodiment described above, the exchanger exchanged heat between two fluids, in other embodiments, the exchanger is adapted to exchange heat between more fluids.

In the embodiment described above, the exchanger included 6 sets of channels of 24 channels each. Obviously, the number of channels per set can be different from 6 and the number of sets can be any number greater than or equal to 1.

In the embodiment described above, the direction of circulation of the fluids f _a and f _b in the intermediate block was opposite. In another embodiment, the direction of circulation is the same.

In the embodiment described, the fluid f _a (similarly the fluid f _b ) circulates successively in each of the blocks 21 to 26. In other embodiments of the invention, the fluid f _a , only performs '' a passage and is supplied simultaneously from the inlet duct 5 by an end block at the inlet of each fluid circulation channel f _a of the intermediate block 2, then is collected by the other end block and is then routed to the outlet conduit (and / or the fluid f _b performs only one passage and is supplied simultaneously by an end block at the inlet of each fluid circulation channel f _b of the intermediate block 2, then in is collected by the other end block). Any intermediate solution can also be implemented (for example, simultaneous supply of a fluid to 3 sets of channels, for example 21, 22, 23 for a first pass, then the fluid collected at the outlet of these channels 21, 22, 23 is redistributed for a second pass at the input of the channels 26, 25, 24 respectively; or else simultaneous supply of a fluid to 2 sets of channels, for three successive passes ...).

In another embodiment, the channels have a rectangular, or round, or triangular cross section, etc. in the plane (X, Z).

In the embodiment described with reference to the figures, the inlet and outlet blocks for the same fluid were on the same side of the intermediate block 2 and the inlet and outlet blocks for the fluid f _a were opposite those of inlet and outlet of the fluid f _b with respect to said intermediate block 2. In another embodiment, the inlet of the fluid f _a is arranged next to the outlet of the fluid f _b , and the inlet of the fluid f _b is placed next to 10 the outlet of the fluid f _a : thus in the structure shown in FIG. 1, the block 7 would be used as the inlet block for the fluid f _b the block 8 as the outlet block for the fluid f _a , the block 5 would be used as the fluid inlet block f _a , block 6 as the fluid outlet block f _b .

Claims (9)

1. - Heat exchanger (1) between at least a first fluid and a second fluid, comprising: at least one set (21) of fluid circulation channels each extending in a longitudinal direction; and distribution and collection means (3, 4), adapted to distribute the first fluid and the second fluid in the channels of at least said assembly; the distribution and collection means being adapted to distribute the first fluid exclusively in first circulation channels of the assembly and to distribute the second fluid exclusively in second circulation channels of the assembly, the exchanger being characterized in that '' at least a first channel is disposed between two second channels along a first axis, said first channel being further disposed between two other second channels along a second axis, at least three of all of said two second channels and said second other channels being one of the channels closest to said first channel. 2, - heat exchanger (1) according to claim 1, wherein the channels are arranged in the form of a matrix in a plane perpendicular to the longitudinal direction, the rows, respectively columns of the matrix being respectively parallel to the first, respectively second axis , and the first channels being arranged in said plane alternately with the second channels along said first and second axes. 3 - Heat exchanger (1) according to claim 1 or 2, wherein the section of the channels in said plane perpendicular to the longitudinal direction of the channels is square. 4, - heat exchanger (1) according to one of the preceding claims, wherein the distribution and collection means (3, 4) are adapted to distribute in a direction the first fluid in the first channels of the assembly and for distribute the second fluid in an opposite direction in the second channels of the assembly. 5, - heat exchanger (1) according to one of the preceding claims, comprising at least said set of fluid circulation channels and another set of fluid circulation channels arranged parallel similar to said assembly and the distribution and collection means (3,4) are adapted: - to distribute the first fluid and the second fluid in the channels of said assembly, - to collect the first fluid and the second fluid when they leave said assembly, - to distribute, in the other assembly and in a direction opposite to the direction of distribution of the first fluid in the assembly, the first fluid collected, - to distribute, in the other assembly and in a direction opposite to the direction of distribution of the second fluid in the assembly, the second fluid collected. 6, - heat exchanger (1) according to claim 5, wherein the distribution and collection means (3,4) comprise at least one channel box comprising: first canister circulation channels of the first fluid connected to the first canals of the channel set and to the first canals of the other set of channels and second canister channels of the second fluid, wherein each second canister channel extends at one of its ends into a second channel of the set of channels and at another of its ends into a second channel of the other set of channels, the second channel rotating in the transverse plane in its portion between said ends and the cross section of the second channel being further reduced in size in said portion, the first channels comprising spaces thus formed between said second channels by said rotation, reduction in size. 7, - Method of heat exchange in a heat exchanger (1) between at least a first fluid and a second fluid, comprising: at least one set (21) of fluid circulation channels each extending in a longitudinal direction; and distribution and collection means (3,4), adapted to distribute the first fluid and the second fluid in the channels of at least said assembly; at least a first channel is disposed between two second channels along a first axis, said first channel being further disposed between two other second channels along a second axis, at least three of the set of said two second channels and said second other channels forming part of the channels closest to said first channel. the process being characterized in that it comprises the following stages: distribution, by means of distribution and collection, of the first fluid exclusively in first circulation channels of the assembly and of the second fluid exclusively in second circulation channels of the assembly. 8- A method of heat exchange according to claim 7, wherein the 5 channels are arranged in the form of a matrix in a plane perpendicular to the longitudinal direction, the lines, respectively columns of the matrix being respectively parallel to the first, respectively second axis, and the first channels being arranged in said plane alternately with the second channels along said first and second axes. 9, - A heat exchange method according to claim 7 or 8, wherein the section of the channels in said plane perpendicular to the longitudinal direction of the channels is square. 10. Heat exchange method according to one of claims 7 to 9, according to which the distribution and collection means (3,4) distribute in a direction the first fluid in the first channels of the assembly and distribute in an opposite direction the second fluid in the second channels of the assembly.