HEAT EXCHANGER AND SYSTEM FOR COOLING A FLUID COMPRISING SUCH A HEAT EXCHANGER

Abstract

A tubular heat exchanger (10) comprising: a fluid circulation chamber (20) intended to be supplied with a first fluid, referred to as outer fluid, brought to a first temperature, a heat exchange matrix (30) housed in said circulation chamber and formed by a plurality of heat exchange tubes (31) each comprising at least one pair of ducts (32; 33) nested one inside the other, extending along a direction, referred to as longitudinal direction, and defining: a channel for circulating a fluid, referred to as inner channel (32c; 33c), suitable for being able to be supplied with a second fluid, referred to as inner fluid, brought to a second temperature, and a channel for the circulation of a fluid, referred to as intermediate channel (32d; 33d), and suitable for being able to be supplied with a third fluid, referred to as intermediate fluid, brought to a third temperature, different from said first temperature.

Claims

1. A heat exchanger (10) comprising: a fluid circulation chamber comprising a fluid inlet and a fluid outlet intended to be supplied with a first fluid, referred to as outer fluid, brought to a first temperature, a heat exchange matrix housed in said circulation chamber and formed by a plurality of heat exchange tubes each comprising at least one pair of ducts nested one inside the other, referred to as inner duct and outer duct, respectively, extending along a direction, referred to as longitudinal direction, and defining: a channel for the circulation of a fluid, referred to as inner channel, delimited by said inner duct, and suitable for being able to be supplied with a second fluid, referred to as inner fluid, brought to a second temperature, and a channel for the circulation of a fluid, referred to as intermediate channel, delimited by the inter-duct space between said inner duct and said outer duct, and suitable for being able to be supplied with a third fluid, referred to as intermediate fluid, brought to a third temperature, different from said first temperature, wherein at least one heat exchange tube comprises at least two pairs of nested ducts, said pairs being connected to each other by at least one transverse spacer.

2. The heat exchanger according to claim 1, wherein at least one heat exchange tube comprises at least two pairs of nested ducts, said intermediate channels of which are supplied by the same intermediate fluid distributor.

3. The heat exchanger according to claim 2, wherein at least one inner duct of at least one pair of nested ducts passes through said intermediate fluid distributor.

4. The heat exchanger according to claim 3, wherein at least one inner duct of at least one pair of nested ducts passes through said intermediate fluid distributor and opens into said circulation chamber.

5. The heat exchanger according to any of claim 1, wherein at least one transverse spacer comprises at least one opening configured to allow the passage of said outer fluid between said pairs of nested ducts connected by this spacer in a direction having an angle of between 0° and 90° with respect to said longitudinal direction.

6. The heat exchanger according to any of claim 1, wherein at least one heat exchange tube comprises at least one pair of nested ducts, the ducts of which are connected to one another by a connecting rod which extends in the intermediate channel between the inner duct and the outer duct.

7. The heat exchanger according to any of claim 1, wherein at least one heat exchange tube comprises at least one pair of nested cylindrical ducts.

8. The heat exchanger according to any of claim 1, wherein, characterized in that at least one heat exchange tube comprises at least one pair of concentric nested ducts.

9. The heat exchanger according to any of claim 1, wherein it further comprises a casing housing said heat exchange tubes, said casing delimiting the fluid circulation chamber.

10. A stem for cooling a fluid exhibiting a first temperature, referred to as hot fluid, with a fluid exhibiting a second temperature, referred to as cold fluid, comprising a hot fluid circuit suitable for being able to be supplied with hot fluid by a hot fluid source, and a cold fluid circuit suitable for being able to be supplied with cold fluid by a cold fluid source, wherein said system further comprises a heat exchanger comprising: a fluid circulation chamber comprising a fluid inlet and a fluid outlet intended to be supplied with a first fluid, referred to as outer fluid, brought to a first temperature, a heat exchange matrix housed in said circulation chamber and formed by a plurality of heat exchange tubes each comprising at least one pair of ducts nested one inside the other, referred to as inner duct and outer duct, respectively, extending along a direction, referred to as longitudinal direction, and defining: a channel for the circulation of a fluid, referred to as inner channel, delimited by said inner duct, and suitable for being able to be supplied with a second fluid, referred to as inner fluid, brought to a second temperature, and a channel for the circulation of a fluid, referred to as intermediate channel, delimited by the inter-duct space between said inner duct and said outer duct and suitable for being able to be supplied with a third fluid, referred to as intermediate fluid, brought to a third temperature, different from said first temperature, wherein at least one heat exchange tube comprises at least two pairs of nested ducts said pairs being connected to each other by at least one transverse spacer said hot circuit supplying said intermediate channels and said cold circuit supplying said inner channels and said circulation chamber of said exchanger.

11. THe cooling system according to claim 10, wherein said intermediate channels and said inner channels are supplied counter-currently by said hot and cold fluids, respectively.

12. An air conditioning system of a cabin of a transport vehicle comprising at least one air cooling system for cooling a fluid exhibiting a first temperature, referred to as hot fluid, with a fluid exhibiting a second temperature, referred to as cold fluid, comprising a hot fluid circuit suitable for being able to be supplied with hot fluid by a hot fluid source, and a cold fluid circuit suitable for being able to be supplied with cold fluid by a cold fluid source, the system further including a heat exchanger comprising: a fluid circulation chamber comprising a fluid inlet and a fluid outlet intended to be supplied with a first fluid, referred to as outer fluid, brought to a first temperature, a heat exchange matrix housed in said circulation chamber and formed by a plurality of heat exchange tubes each comprising at least one pair of ducts nested one inside the other, referred to as inner duct and outer duct, respectively, extending along a direction, referred to as longitudinal direction, and defining: a channel for the circulation of a fluid, referred to as inner channel, delimited by said inner duct, and suitable for being able to be supplied with a second fluid, referred to as inner fluid, brought to a second temperature, and a channel for the circulation of a fluid, referred to as intermediate channel, delimited by the inter-duct space between said inner duct and said outer duct and suitable for being able to be supplied with a third fluid, referred to as intermediate fluid, brought to a third temperature, different from said first temperature, wherein at least one heat exchange tube comprises at least two pairs of nested ducts said pairs being connected to each other by at least one transverse spacer said hot circuit supplying said intermediate channels and said cold circuit supplying said inner channels and said circulation chamber of said exchanger.

13. An air, rail or automotive transport vehicle comprising at least one propulsion engine, a cabin and at least one air conditioning system for said cabin, characterized in that the air conditioning system of the cabin is an air conditioning system for cooling a fluid exhibiting a first temperature, referred to as hot fluid, with a fluid exhibiting a second temperature, referred to as cold fluid., comprising a hot fluid circuit suitable for being able to be supplied with hot fluid by a hot fluid source, and a cold fluid circuit suitable for being able to be supplied with cold fluid by a cold fluid source, the system further including a heat exchanger comprising: a fluid circulation chamber comprising a fluid inlet and a fluid outlet intended to be supplied with a first fluid, referred to as outer fluid, brought to a first temperature, a heat exchange matrix housed in said circulation chamber and formed by a plurality of heat exchange tubes each comprising at least one pair of ducts nested one inside the other, referred to as inner duct and outer duct, respectively, extending along a direction, referred to as longitudinal direction, and defining: a channel for the circulation of a fluid, referred to as inner channel, delimited by said inner duct, and suitable for being able to be supplied with a second fluid, referred to as inner fluid, brought to a second temperature, and a channel for the circulation of a fluid, referred to as intermediate channel, delimited by the inter-duct space between said inner duct and said outer duct and suitable for being able to be supplied with a third fluid, referred to as intermediate fluid, brought to a third temperature, different from said first temperature, wherein at least one heat exchange tube comprises at least two pairs of nested ducts said pairs being connected to each other by at least one transverse spacer said hot circuit supplying said intermediate channels and said cold circuit supplying said inner channels and said circulation chamber of said exchanger.

Description

LIST OF FIGURES

[0086] Further aims, features and advantages of the invention will become apparent upon reading the following description, which is provided solely by way of non-limiting example, and which refers to the accompanying figures, in which:

[0087] FIG. 1 is a schematic cross-sectional view of an exchanger according to one embodiment of the invention.

[0088] FIG. 2 is a schematic perspective view of a plurality of heat exchange tubes forming the heat exchange matrix of an exchanger according to one embodiment of the invention.

[0089] FIG. 3a is a schematic front perspective view of a tube of an exchanger according to one embodiment of the invention.

[0090] FIG. 3b is a schematic rear perspective view of a tube of an exchanger according to one embodiment of the invention.

[0091] FIG. 4a is a schematic front perspective view of a tube of an exchanger according to another embodiment of the invention.

[0092] FIG. 4b is a schematic rear perspective view of a tube of an exchanger according to another embodiment of the invention.

[0093] FIG. 5 is a schematic view of a heat exchange matrix of an exchanger according to one embodiment of the invention.

[0094] FIG. 6 is a schematic view of a heat exchange matrix of an exchanger according to one embodiment of the invention.

[0095] FIG. 7 is a schematic view of an aircraft according to one embodiment of the invention.

DETAILED DESCRIPTION OF ONE EMBODIMENT OF THE INVENTION

[0096] For the sake of illustration and clarity, scales and proportions are not strictly adhered to in the figures. In the whole of the detailed description which follows with reference to the figures, unless otherwise indicated, each element of the tubular heat exchanger is described as it is arranged when the exchanger is housed in an air circulation duct which extends along a direction, referred to as longitudinal direction, which coincides with the direction along which the heat exchange tubes of the exchanger extend. This configuration is shown in particular in FIG. 1.

[0097] Moreover, identical, similar or analogous elements are denoted using the same reference signs throughout the figures.

[0098] Throughout the following, the description considers that the heat exchanger is installed within an air conditioning system, it being understood that the exchanger can be used for applications other than the cooling of a high air temperature, taken, for example, from a propulsion engine of an aircraft.

[0099] FIG. 1 schematically illustrates a tubular heat exchanger 10 embedded in an air circulation duct 23. The exchanger may comprise a casing embedded in the duct 23.

[0100] The exchanger 10 further comprises a heat exchange matrix 30, housed in a fluid circulation chamber 20, and formed by a plurality of heat exchange tubes 31 extending in a longitudinal direction 70, which coincides, for example, with the direction along which the duct 23 extends.

[0101] The chamber 20 is supplied with air brought to a first temperature. This air is, for example, air taken from outside the aircraft. This fresh air is schematically illustrated by the arrow referenced 72a in FIG. 1.

[0102] The heat exchange tubes 31 are Y-shaped in the embodiment of FIGS. 2, 3a, 3b, 5 and 6, the base of the Y forming a distributor 50 for supplying intermediate channels, forming the branches of the Y, with intermediate air brought to a second temperature, different from the temperature of the air supplying the chamber 20. This intermediate air is, for example, hot air taken from the propulsion engines of the aircraft. This hot air is schematically illustrated by the arrow referenced 71 in FIG. 1.

[0103] The tubes 31 are also configured to have inner channels supplied with fresh air, which may be the same air as that which supplies the chamber 20. This air is schematically illustrated by the arrow 72b in FIG. 1. According to another embodiment, the inner channels can be supplied with air brought to another temperature different from the temperatures of the outside air and of the intermediate air.

[0104] FIG. 2 provides a more detailed illustration of a portion of the heat exchange matrix of an exchanger according to the invention. Each tube comprises two pairs 32; 33 of conjugated concentric ducts connected to an intermediate fluid distributor 50. The distributor 50 comprises an intermediate fluid inlet 51 supplied by a supply system not shown in detail in the figures and two fluid outlets 52 making it possible to supply the intermediate channels 32d and 33d of the pairs 32; 33 of ducts nested one inside the other. The two pairs 32, 33 of ducts are interconnected by means of a transverse spacer 40 which further comprises an opening 41 allowing the passage of the air circulating in the chamber 20.

[0105] FIGS. 3a and 3b illustrate a Y-shaped tube 31. The Y-shaped tube 31 can be manufactured by an additive printing system, such as a 3D printer.

[0106] As illustrated in these figures, the Y-shaped tube 31 comprises two pairs 32; 33 of ducts nested one inside the other, which are also concentric in the embodiment of the figures. Each pair of ducts is formed by two nested ducts, an inner duct 32a; 33a and an outer duct 32b; 33b, respectively.

[0107] The inner ducts 32a; 33a delimit an inner channel 32c; 33c for circulation of the inner air, which is, for example, cold air.

[0108] The inter-duct space formed by the inner duct 32a; 33a and the outer duct 32b; 33b defines an intermediate channel 32d; 33d for the circulation of intermediate air, which is, for example, hot air.

[0109] The outer duct 32b; 33b is connected to the two fluid outlets 52 of the distributor 50 so that the intermediate fluid supplying the distributor through the inlet 51 is distributed to the intermediate channels 32d; 33d.

[0110] The inner channel 32c; 33c of each pair of ducts opens into the fluid circulation chamber 20 so that the air flow circulating in the inner channel is the air flow circulating in the chamber 20. To do this, the outlets 52 of the distributor 50 connected to the outer ducts 32b; 33b are passed through by the inner duct 32a; 33a, which opens directly into the fluid circulation chamber 20 so that the chamber 20 and the inner channels are supplied by the same flow of fresh air.

[0111] The matrix 30 is formed by Y-shaped tubes 31, the pairs of conjugated concentric ducts 32; 33 of which are parallel to each other. The Y-shaped tubes 31 are combined with each other to form a layer of tubes 31. A plurality of layers can be stacked on top of each other so as to constitute a matrix network of tubes 31 within a chamber 20 to form the matrix 30. The layers of Y-shaped tubes 31 can be stacked so that the inlets 51 of all the distributors 50 are staggered with respect to each other, thus creating spaces for the passage of the outer fluid circulating in the chamber 20.

[0112] FIGS. 4a and 4b illustrate a tube according to another embodiment of the invention. In this embodiment, the tube comprises a distributor 50 and three pairs of nested ducts 32, 33, 34 nested one inside the other. In addition, the distributor 50 supplies the three pairs 32, 33, 34 of ducts in parallel from a single supply of the distributor.

[0113] According to other embodiments not shown, a tube may comprise four or more pairs of nested ducts.

[0114] In FIG. 5, on either side of the inlet 51 of the distributor 50, one can see the inner channels 32c and 33c in which the inner fluid circulates which also supplies the chamber 20 in which the heat exchange matrix 30 is housed (not shown in this figure).

[0115] FIG. 6 schematically illustrates the pairs of nested ducts 32; 33 and in particular the outer ducts 32b and 33b, which are interconnected by the transverse spacer 40.

[0116] According to this embodiment, the heat exchanger 10 can be integrated into an air conditioning system 62. In addition, the tubes 31 as illustrated are cylindrical and thus make it possible to obtain a cylindrical matrix 30 which can be housed in a chamber 20 delimited by a cylindrical casing, which can be integrated into a cylindrical air circulation pipe and in particular into an air conditioning system 62 equipping an aircraft 60.

[0117] As illustrated by FIG. 7, the air conditioning system 62 comprises a hot circuit and a cold circuit intended to supply the tubular exchanger according to the invention. The intermediate fluid is the fluid conveyed by the hot circuit and is, for example, air taken from the propulsion engines 61 of the aircraft. The cold circuit which makes it possible to supply the inner fluid and the outer fluid is, for example, a circuit of air taken from the secondary flow of the engine or air taken from outside the aircraft.

[0118] The tubular heat exchanger 10 can be directly embedded in an air circulation pipe, and in particular in an air conditioning system 62 which equips an aircraft 60. According to this embodiment, the size of the exchanger 10 is thus limited while having an increased heat exchange surface with a system of nested ducts allowing a double heat exchange.

[0119] The present invention has been described in conjunction with an aeronautical application, in particular for an air conditioning system for an aircraft cabin.

[0120] This being the case, a heat exchanger according to the invention can be implemented not only in the context of the air conditioning systems of a transport vehicle, such as an aircraft, but also in all types of cooling systems requiring the cooling of a hot fluid from a hot fluid source by a cold fluid from a cold fluid source.

[0121] As such, a heat exchanger according to the invention can equip not only systems as described in application EP3342709 in the applicant's name, but also systems as described in applications EP3190282, WO201634830, EP3392146, WO2018122334, FR2894563 or FR3051894. This list is, of course, not limiting and is only cited to enable a person skilled in the art to perceive the potential for application of a heat exchanger according to the invention.