FR2871876A1 - HEAT EXCHANGE DEVICE HAVING SEVERAL ROWS OF TUBES, ESPECIALLY FOR MOTOR VEHICLES - Google Patents

Abstract

The heat exchange device of the invention comprises at least two parallel rows of tubes (40; 46) opening respectively into at least two adjacent manifolds (36; 42) via respective manifolds (38; 44). . The two manifolds are arranged substantially at the same height in the axial direction (D1, D2) of the tubes, each manifold has two parallel longitudinal edges protruding from both sides of the row and arranged at different heights in the axial direction of the tubes to form a close edge (48, 52) and a far edge (50, 54), the far edge (54) of the header (42) being received in a recess (56) disposed proximate the close edge (48) of the manifold (36), which allows a saving of space of the heat exchanger. Application in particular to motor vehicles.

Description

VCL1545.FRD.wpd

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

  It relates more particularly to a heat exchange device comprising at least two parallel rows of tubes respectively opening into at least two adjacent manifolds via respective collectors.

  Such a heat exchange device can be realized, for example, in the form of a module comprising at least two different heat exchangers each having a parallel row of tubes. A typical example, in the field of motor vehicles, is a module consisting of the assembly of a cooling radiator of an engine and an air conditioning condenser. In such a module, the condenser is usually placed in front of the cooling radiator in the longitudinal (X-axis) direction of the vehicle.

  A device of this type can also be realized in the form of a single heat exchanger in which each tube of a row is connected to a tube of the other row by a bend to form a U-shaped or pin-shaped tubular structure. .

  A typical example is a gas cooler for a supercritical fluid.

  In heat exchange devices of this type, the manifolds that receive the rows of tubes have a significant size because they must have protruding longitudinal edges protruding from either side of each row of tubes. . In other words, the width of the manifold, as defined by the two longitudinal edges mentioned above, is necessarily greater than the width of each tube, in the same direction.

  It is indeed necessary that each manifold exceeds both sides of the row of tubes that it receives to provide openings for receiving the ends of the tubes.

  This therefore results in a bulk in a direction perpendicular to the rows of tubes, that is to say a bulk in the direction of the X axis, if we take the example of an exchange module of heat as defined previously.

  When two adjacent manifold boxes are located at the same axial height of the tubes, they each have respective adjacent longitudinal edges, which must additionally be mutually spaced to avoid contact between the two manifolds. This space is necessary to avoid in particular thermal conduction between the manifolds. This conduction would itself be detrimental to the overall thermal efficiency of the exchanger.

  In other words, the total space between two tubes belonging to adjacent rows is the addition of the offsets of the collectors and the offset between the collectors.

  Various solutions have already been envisaged to reduce the overall width of such a heat exchange device.

  JP 2001-133187 proposes axially shifting one row of tubes relative to the other, which also causes axial shift of the manifolds. However, this solution increases the overall height of the device, that is to say in the axial direction of the tubes.

  JP 2002-318092 proposes to cut the end of the tubes. But this solution has the main disadvantage of reducing the width of the tubes actually used for the circulation of the fluid inside the tubes.

  Another possible solution is to twist the end of the tube. However, this solution has two main disadvantages. It is necessary to have an additional process operation to achieve this twist. In addition, it is not possible to provide fins in the region of the end of the tube which has undergone torsion.

  Thus, until now, no satisfactory solution has been found to solve the aforementioned congestion problem. This problem arises from the fact that the width of the header is necessarily greater than that of the tube, so that the width or depth of the device is greater than the sum of the widths of two tubes.

  The invention proposes another solution to solve this congestion problem.

  According to the invention, the two manifolds are arranged substantially at the same height in the axial direction of the tubes, and each manifold has two parallel longitudinal edges protruding on either side of the row and arranged at different heights in the axial direction of the tubes to form a close edge and a far edge, the far edge of a first manifold being received in a recess arranged near the close edge of a second manifold.

  In other words, the collector boxes are arranged at the same axial height, but they have respective collectors which are inclined, this inclination resulting from the fact that each collector box has two longitudinal edges arranged at different heights in the axial direction of the tubes. These two longitudinal edges respectively constitute a close edge and a far edge, the close edge of a first manifold being received in a recess arranged near the far edge of a second manifold.

  As a result, the space between two adjacent tubes (belonging to two different rows) results from the addition of two values, namely on the one hand the offset of a longitudinal edge of a collecting box, and of on the other hand the difference between this longitudinal edge and the tubes of the other row.

  According to an advantageous feature of the invention, the far edge of the first manifold and the recess of the second manifold have conjugate shapes.

  It is also advantageous if the two manifolds are of identical shapes, for reasons of standardization of the boxes or means for obtaining these boxes.

  According to yet another characteristic of the invention, the respective collectors of the two collector boxes have a substantially plane bottom, in which are arranged openings for the reception of the tubes, which extends between the near edge and the far edge forming a acute angle to a plane perpendicular to the tubes. This acute angle is advantageously between 5 and 50.

  It is also advantageous that the tubes have shaped ends received in the openings of the respective manifold. These shaped ends advantageously have a beveled shape delimited by a cutting plane substantially parallel to the plane of the bottom of the collector.

  In a first general embodiment of the invention, the two rows of tubes respectively belong to two different heat exchangers. For example, one of the two heat exchangers may be a cooling radiator of an engine and the other an air conditioning condenser. These two heat exchangers can then be assembled to form a module.

  In a second general embodiment of the invention, the two rows of tubes belong to the same heat exchanger, each tube of a row being connected to a tube of the other row by a bend to form a tubular structure. U or pin. In this case, the heat exchanger is advantageously a gas cooler for a supercritical fluid.

  In the description which follows, given by way of example only, reference is made to the accompanying drawings, in which: FIG. 1 is a partial sectional view of a heat-exchange device of the prior art; FIG. 2 is a partial sectional view of a heat exchange device 20 according to a first embodiment of the invention; FIG. 3 is a partial sectional view of a heat exchange device according to a second embodiment of the invention; - Figure 4 is a partial sectional view of a heat exchange device according to a third embodiment of the invention; - Figure 5 is a sectional view of a heat exchange device according to the invention comprising two different heat exchangers assembled to form a module; and FIG. 6 is a sectional view of a heat exchange device according to the invention made in the form of a single heat exchanger comprising U-shaped or pin-shaped tubes.

  Referring first to Figure 1 which shows a heat exchange device of the prior art, designated as a whole by the reference 10. This device comprises two heat exchangers 12 and 14 assembled to form a module. The exchanger 12 comprises a manifold 16 provided with a manifold 18 in which the ends of a first row of tubes 20 open.

  Correspondingly, the exchanger 14 comprises a manifold 22 provided with a manifold 24 into which the ends of a second row of tubes 26 open. The two rows of tubes 20 and 26 are parallel to each other and to the manifolds 16 and 22 are located at the same height with respect to the axial direction D1 and D2 of the tubes, which corresponds to the X axis in the drawing. As can be seen in FIG. 1, the manifolds each have an overall width (or depth) in the direction of the X axis, which is greater than the width, in the same direction, of the tubes. In FIG. 1, L is denoted by the width of the manifold 16 and by 1 the width of each tube 20.

  The manifold 22 may have a width identical or not to that of the manifold 20, this width being there also greater than the width of the tubes 26. As a result, between the rows of tubes 20 and 26, there is a gap E which results from the addition of three values: the offset D1 of a longitudinal edge of the collector 18, the offset D2 between this longitudinal edge and the adjacent longitudinal edge of the collector 24 and the offset D3 of the longitudinal edge of this collector 24.

  The invention makes it possible to reduce the value of the space E by particular characteristics which will now be described with reference to FIG. 2.

  As can be seen in FIG. 2, the heat exchange device 30 according to the invention comprises two heat exchangers 32 and 34 which, in the example, are assembled to form a module. The exchanger 32 comprises a manifold 36 provided with a manifold 38 in which are received the ends of a first row of tubes 40 which each extend in an axial direction D1, parallel to the Z axis (perpendicular to the X axis).

  Correspondingly, the heat exchanger 34 comprises a manifold 42 provided with a manifold 44 in which are received the ends of a second row of tubes 46 which extend in an axial direction D2 parallel to the axial direction D1 .

  As can be seen in FIG. 2, the two manifolds 36 and 42 are arranged substantially at the same height in the axial direction of the tubes 40 and 46. However, each manifold has two longitudinal protruding edges, which are arranged at different axial heights.

  Thus, the manifold 36 has a close edge 48 and a far edge 50. The terms "close" and "far" are used here for convenience to express the fact that these edges are at different axial heights. The close edge 48 is closer to the bottom of the drawing than is the far edge 50.

  Correspondingly, the manifold 42 has a close edge 52 and a far edge 54. The two near edges 48 and 52 are located substantially at the same axial height and the same is true for the far edges 50 and 54, which allows the manifolds to be at substantially the same axial height.

  The remote edge 54 of the manifold 42 is received here in a recess 56 arranged near the close edge 48 of the manifold 36, which allows a saving of space in the direction of the X axis. Advantageously the edge 54 and the recess 56 have conjugate forms to allow an adaptation of their respective forms, but these two forms do not come into contact with each other.

  As a result, the space E 'between the tubes 40 and 44 is smaller than in the prior art (FIG. 1). This space results solely from the sum of the offset D'1 of the close edge 48 of the manifold 36 and the offset D'2 between the close edge 48 and the tubes 46. This eliminates the offset of the far edge 54 of the manifold 42, since this far edge is received in the recess 56 above.

  As the edges 48 and 50 of the manifold 36 and the edges 52 and 54 of the manifold 42 are at different axial heights, the respective manifolds 38 and 44 of these boxes are inclined. This inclination corresponds to an angle A with respect to a plane perpendicular to the axis of the tubes. This angle A is acute and is advantageously between 5 and 50. The collectors 38 and 44 each have a flat bottom in which are provided openings (not shown) for receiving the tubes.

  It is advantageous that the ends of the tubes are also shaped according to the oblique nature of the aforementioned collectors. Thus, as can be seen in Figure 2, the tubes 40 and 46 have respective ends 58 and 60 which have a beveled shape defined by a cutting plane substantially parallel to the plane of the bottom of the collector. In other words, the bevel cut is made at the same angle A. It is advantageous that the manifolds 36 and 42 are identical for reasons of standardization. Under these conditions, the manifold 42 has a recess 62 similar to the recess 56 of the manifold 36. This recess in principle has no function. It can, however, be used to receive the far edge of a third header, in the case where the device results from the assembly of three different exchangers. Indeed, the principle of the invention applies generally to heat exchanger devices comprising at least two parallel rows of tubes.

  The tubes 40 and 46 are provided with respective fins 64 and 66, here flat fins, and have end regions 68 and 70 which are free of fins due to the oblique configuration of the collectors.

  Figure 3 and Figure 4 show similar devices to that of Figure 2, in which the manifolds have different shapes.

  Referring now to Figure 5 which shows a heat exchange device similar to that of Figure 2. It is seen that the heat exchanger 32 comprises at its other end, a manifold 72 similar to the manifold 36 and that the heat exchanger 34 comprises at its other end a manifold 74 similar to the manifold 42. The manifolds 72 and 74 are disposed substantially at the same height in the axial direction of the tubes and they have respective collectors arranged obliquely to allow a gain in space.

  FIG. 6 shows another heat exchange device 76 according to the invention in which each tube 40 of a row is connected to a tube 46 of another row by a bend 78 to form a U-shaped tubular structure or pin.

  In other words, the device 76 here constitutes a single heat exchanger.

  The device of the invention finds a general application to heat exchangers for motor vehicles.

  In the case where the device comprises two different heat exchangers, as is the case of the device of Figure 5, one of the exchangers, for example the exchanger 32, can constitute an air conditioning condenser and the other exchanger , for example the exchanger 34, can constitute a cooling radiator of a motor.

  These two exchangers can be mutually assembled to form a module. In such a module, the two heat exchangers may have different respective fins or share common fins.

  In the case where the heat exchange device constitutes a single heat exchange as shown in Figure 6, the device is used to exchange heat with a single fluid. It can be realized, for example, in the form of a device for cooling the exhaust gases from a motor vehicle combustion engine, a condenser or an air-conditioning evaporator, a cooler of gas for a supercritical fluid such as carbon dioxide, or a charge air cooler of a motor vehicle engine.

  It will be understood that the device of the invention is capable of numerous variants and different applications.

  The manifolds, manifolds, tubes and fins may be joined together by mechanical means, for example by crimping, brazing, or any combination thereof.

  The shape of the tubes of the exchangers is also capable of many variants and the term "tube" is to be considered here in the broad sense as designating any means forming channels for circulation of a fluid.

  Although the invention has been described with particular reference to a device comprising two rows of tubes, it can generally be applied to devices comprising more than two rows of tubes, for example three rows of tubes, or more.

Claims (12)

claims   A heat exchange device comprising at least two parallel rows of tubes respectively opening into at least two adjacent header boxes via respective manifolds, characterized in that the two manifolds (36, 42) are arranged substantially at the same height in the axial direction (D1, D2) of the tubes (40, 46), in that each collecting box has two parallel longitudinal edges (48, 50; 52, 54) protruding from both sides of the arranged at different heights in the axial direction of the tubes to form a close edge (48; 52) and a far edge (50; 54), and that the far edge (54) of a first box collector (42) is received in a recess (56) disposed near the close edge (48) of a second header (36).   2. Device according to claim 1, characterized in that the remote edge (54) of the first header (42) and the recess (56) of the second manifold (36) have conjugate shapes.   3. Device according to one of claims 1 and 2, characterized in that the shapes of the two manifolds (36, 42) are identical.   4. Device according to one of claims 1 to 3, characterized in that the respective collectors (38; 44) of the two manifolds (32, 34) have a substantially plane bottom (39, 45), in which are arranged apertures for receiving the tubes, which extends between the near edge and the far edge forming an acute angle (A) with respect to a plane perpendicular to the tubes.   5. Device according to claim 4, characterized in that the acute angle (A) is between 5 and 50.   6. Device according to one of claims 4 and 5, characterized in that the tubes (40, 46) have shaped ends (58, 60) received in the openings of the respective manifold.   7. Device according to claim 6, characterized in that the shaped ends (58, 60) of the tubes have a beveled shape delimited by a cutting plane substantially parallel to the plane of the bottom of the collector.   8. Device according to one of claims 1 to 7, characterized in that the two rows of tubes (40, 46) belong respectively to two different heat exchangers (32, 34).   9. Device according to claim 8, characterized in that one of the two heat exchangers (32, 34) is a cooling radiator of an engine and the other an air conditioning condenser.   10. Device according to one of claims 8 and 9, characterized in that the two heat exchangers {32, 34) are assembled to form a module.   11. Device according to one of claims 1 to 7, characterized in that the two rows of tubes (40; 46) belong to the same heat exchanger (76), each tube (40) of a row being connected to a tube (46) of the other row by a bend (78) to form a U-shaped or pin-shaped tubular structure.   12. Device according to claim 11, characterized in that the heat exchanger is a gas cooler for a supercritical fluid.