Plate For Heat Exchanger And Heat Exchanger Equipped With Such Plates

Abstract

The invention relates to a plate intended to enable an exchange of heat between a first and a second fluid circulating in contact with the plate, said plate being configured to define a circuit for the first fluid. According to the invention, said plate comprises one or a plurality of protuberances intended to penetrate into a plate for collecting the first fluid and defining an inlet into and/or an outlet from the circuit. The invention also relates to an array of such plates and to a heat exchanger comprising such an array.

Description

The invention relates to plates for heat exchangers and to plate heat exchangers, in particular for motor vehicles.

Exchangers, known as charge air coolers, permitting an exchange of heat between charge air, intended to supply the engine of the vehicle, and a coolant liquid are familiar in this field. They comprise a heat exchange array including a stack of plates determining between them alternate circulation channels for the charge air and for the coolant liquid.

Each plate guides the coolant liquid in a circuit comprising a plurality of passageways. These plates exhibit the general shape of an elongated rectangle having two large sides and small sides, each plate including two bosses, a first boss exhibiting an inlet into the circuit for the circulation of the coolant liquid and the other boss exhibiting an outlet from the circuit for the circulation of the coolant liquid. The bosses are situated along one and the same small side of the plate. They are intended to come into contact with the bosses of an adjacent plate in order to permit the coolant liquid to pass from one circulation channel to another. The coolant fluid is thus distributed between the plates via the inlet bosses. It then flows along passageways in the circuits for the circulation of coolant liquid before exiting from said plates at the level of the outlet bosses.

The charge air enters into the array at the level of one of the large sides of each plate before exiting therefrom at the level of the other of the large sides. Each plate thus comprises a zone for the exchange of heat between the coolant liquid and the charge air situated at the level of the passageways and an inlet/outlet zone permitting the coolant liquid to enter into and to exit from each plate.

One disadvantage derives from the fact that the zone inside which the bosses are situated concentrates mechanical stresses capable of causing rupture of the elements that are brazed to one another. Another disadvantage derives from the fact that this zone is highly prejudicial to the thermal performance because the charge air passing through this zone, in particular between the bosses and the first longitudinal extremity of the plate, does not pass through the exchange zone between the two fluids and accordingly exchanges no heat or almost no heat with the coolant liquid.

A well-known approach to circumventing this problem is to modify the component parts of the exchanger or to add a supplementary part constituting a screen and permitting the passage through this zone of the fluid to be cooled to be limited. This has the effect of complicating the component parts and/or the process of manufacturing of the exchanger, however, which can give rise to additional costs and, possibly, to an increase in the weight of the exchanger.

The object of the invention is to improve the situation.

To this end, it proposes a plate intended to permit an exchange of heat between a first and a second fluid circulating in contact with the plate, said plate being configured so as to define a circuit for the first fluid.

According to the invention, said plate comprises one or a plurality of protuberances intended to penetrate into a collector plate for the first fluid and defining an inlet into and/or an outlet from the circuit.

The zone of each plate for the exchange of heat between the two fluids is increased in size in this way, and the zone of each plate which does not participate in the exchange of heat is reduced in size. In fact, the only part of a plate that does not participate directly in the exchange of heat is situated at the level of the protuberances. It can also be appreciated that the protuberances, by being oriented in a different way, are subjected to fewer stresses than the inlet/outlet zones for the first fluid, comprising bosses, of the known plates.

According to one aspect of the invention, said plate comprises two protuberances. For example, the plate comprises one inlet protuberance, through which the first fluid is able to enter, and one outlet protuberance, through which the first fluid is intended to exit.

According to another aspect of the invention, said plate comprises two small sides and two large sides, such that said plate possesses the shape of a rectangle, the one or a plurality of said protuberances being situated at the level of the small sides of the rectangle.

According to one illustrative embodiment, said plate and said protuberances comprise a bottom and margins defining said circuit, said bottom of the one or a plurality of said protuberances and said bottom of said plate extending in one and the same plane. The bottom of the one or a plurality of protuberances possesses, for example, one distal extremity lacking margins such that the first fluid is able to enter into and/or to exit from the circuit via the distal extremity of the protuberances.

According to another illustrative embodiment, the margins delimiting the circuit are parallel to one other at the level of the one or a plurality of protuberances and are flared out in the direction of the rest of the circuit. They can continue to be parallel to one other as far as a zone in which a change takes place in the direction of flow of the first fluid. The margins thus take the form of a funnel in proximity to the protuberances. The expression proximity is used here to denote a zone situated between 0 and 30 mm from the protuberance.

The invention also relates to an array for the exchange of heat comprising a stack of plates of the kind described previously, said plates being arranged in pairs such that two plates of the same pair determine between them a circulation channel for the first fluid. Similarly, two plates arranged opposite one another and belonging to two pairs of adjacent plates determine between them a circulation channel for the second fluid.

The invention also relates to a heat exchanger comprising an array for the exchange of heat as described previously and said collector plate, intended to be passed through by said protuberances of said plates.

According to one aspect of the invention, said exchanger comprises a housing provided with four walls and in the interior of which housing said array is present, one of the four walls being said collector plate. The collector plate is a lateral wall of the housing, for example, that is to say a plate situated opposite a peripheral lateral edge of the plates provided with the protuberances.

According to a further aspect of the invention, said heat exchanger comprises at least one inlet collector, into the interior of which the protuberances of said plates defining the inlet of said circuits discharge, and one outlet collector, into the interior of which the protuberances of said plates defining the outlet from said circuits discharge. In this way, the one or a plurality of inlet and/or outlet collectors is present on the exterior of the housing, that is to say on the exterior of the array, such that the array in its entirety participates in the exchange of heat between the two fluids.

According to one illustrative embodiment, the collector plate comprises a plane section and collars surrounding said protuberances. The collars participate in the mechanical support of the plates in relation to the housing and conform to the contour of the protuberances in such a way that the two fluids are separated in an impermeable manner.

According to one aspect of the invention, the margins of the protuberances are terminated as a flat surface permitting the brazing of the protuberances to one another and extending in a plane parallel to the plane in which the bottom of the protuberances extends. Two plates forming a pair of plates are in contact at the level of an internal surface of the flat surfaces. The collars conform to an external surface of the margins of the protuberances and to an external surface of the bottom of the protuberances, a lateral surface of the flat surfaces then having the ability to come into contact with the plane section of the collector plate. Each collar surrounding the protuberances of one pair of plate thus comprises an upper part and a lower part, the lower part of the collar being in contact with the protuberance of a lower plate of the pair of plate, and the upper part of the collar being in contact with the protuberance of an upper plate of the pair. The lower part and the upper part of each collar are not in contact with one another.

According to one aspect of the invention, baffles are arranged inside the exchanger, said baffles extending between two pairs of plates until they are in proximity to said collector plate. In this way, the baffles disrupt the flow of the second fluid circulating between the pairs of plates from one lateral wall of the housing to the other. The expression proximity is used here to denote a distance between 0 and 1 mm.

The invention also relates to a module for the admission of air comprising an exchanger of the kind described previously.

Other characterizing features and advantages of the invention will become even more evident from a perusal of the following description of illustrative embodiments provided by way of example with reference to the accompanying figures. In these figures:

FIG. 1 is a view in perspective illustrating partially a heat exchanger comprising plates according to the invention;

FIG. 2 is a view from above of a plate of the exchanger in FIG. 1;

FIG. 3 is a partial view in perspective of a collector plate that is passed through at the level of collars by the protuberances of the plates of the exchanger, and

FIG. 4 is a partial view illustrating the side of the exchanger exhibiting the collector plate.

As illustrated in FIG. 1, the invention relates to a heat exchanger 1 permitting an exchange of heat between a first fluid, for example a coolant liquid C, and a second fluid, in particular a fluid to be cooled G. It can be a charge air cooler, inside which the fluid to be cooled is a flow of compressed air intended to supply an internal combustion engine, for example an engine of a motor vehicle. This flow of compressed air is cooled by the coolant liquid, in particular in the form of a mixture of water and glycol.

Said exchanger 1 comprises an array 2 for the exchange of heat comprising a stack of plates 4 determining between them alternate circuits 6, 8 for the coolant liquid C and for the fluid to be cooled G. The array 2 in this case is of generally parallepipedal shape and exhibits an inlet surface 10 and an opposing outlet surface, although not depicted here, for the second fluid G. The plates 4 in this case are arranged in pairs in such a way that two plates 4 of one and the same pair determine between them a circulation channel for the coolant liquid C. The circuits 6 for the circulation of the fluid to be cooled G are provided between two plates 4 arranged opposite two pairs of adjacent plates.

The exchanger can also comprise a housing 5, inside which the array 2 is situated. In this case, it comprises a left-hand lateral wall 18 situated to the left in FIG. 1 and a right-hand lateral wall 19 situated to the right in FIG. 1. The left-hand lateral wall 18 comes into contact with left-hand lateral edges (reference 16 in FIG. 2) of the plates 4, whereas the right-hand lateral wall 19 comes into contact with right-hand lateral edges (reference 17 in FIG. 2) of the plates 4. The housing 5 likewise comprises an upper wall (not illustrated here) and a lower wall 22 linking together the lateral walls 18, 19. The housing 5 guides the fluid to be cooled G between the plates 4, from the inlet surface 10 as far as the outlet surface of the array 2.

The exchanger 1 may also comprise secondary exchange surfaces arranged inside the circuits 6 for the circulation of the second fluid. The secondary exchange surfaces extend between two plates 4 arranged opposite one another belonging to two pairs of adjacent plates. The secondary exchange surfaces in this case comprise corrugated baffles 52 inserted between the plates inside the circuits 6 for the circulation of the fluid to be cooled.

FIG. 2 depicts a plate 4 according to the invention. Such a plate 4 includes a bottom 31, for example, which is substantially plane, surrounded by a peripheral margin 32 terminated by a flat surface 34, permitting the brazing of the plates to one another. The circuit 8 for the coolant liquid is defined, on the one hand, by said peripheral margin 32 and, on the other hand, by one or a plurality of central margins 60, for example, arising from the material of the bottom 31 of the plate. The plates 4 possess the general shape of an elongated rectangle, for example, having two large sides and two small sides corresponding to the lateral edges 16, 17.

According to the invention, each plate includes two protuberances 38, 39 intended to penetrate into a collector plate for the coolant liquid (corresponding to the left-hand lateral wall 18 in FIG. 1) and defining an inlet 40 into and/or an outlet 42 from the circuit 8. In this case, an inlet protuberance 38 of said protuberances exhibits the inlet 40, and an outlet protuberance 39 exhibits the outlet 42.

The protuberances 38, 39 are situated on the small sides 16, 17 of the plate, in this case at the level of the small side 16 situated on the left in FIG. 2. They comprise a bottom 43 and margins 44 respectively extending the bottom 31 and the margins 32 of the plate 4 towards the exterior of the latter, that is to say beyond its lateral edge 16. The protuberances 38, 39 thus project in relation to the bottom 31 of the plate 4. The bottom 43 of the protuberances 38, 39 extends, for example, in the plane in which the bottom 31 of the plate 4 extends. The protuberances 38, 39 possess one distal extremity 45 lacking margins and two lateral extremities provided with margins 44. The coolant liquid is thus able to penetrate into or exit from the plate 4 via the distal extremity 45 of the protuberances 38, 39 and to be guided inside the circuit 8 of the plate 4 via the base 31, 42 and the margins 32, 60, 44 of the protuberances 38, 39 and of the plate 4.

Like the peripheral margins 32 of the plates 4, the protuberances 38, 39 are terminated by a flat surface 46, which extends in a plane parallel to the bottom 43 of the protuberances 38, 39. The inlet protuberances 38 and/or the outlet protuberances 39 of one and the same pair of plate are in contact with and brazed to one another at the level of an internal surface of these flat surfaces 46.

The margins 32, 44, 60 are parallel to one other at the level of the protuberances 38, 39. They are of flared shape in proximity to the protuberances 38, 39, that is to say that they are of flared shape in a zone lying, in particular, between 0 and 30 mm from the protuberances. This flaring of the margins 32, 44, 60 makes it possible to enlarge the circuit 8 for the circulation of the coolant liquid in the event that the widening is present in proximity to the inlet protuberance 38, and to reduce the circuit 8 for the circulation of the coolant liquid in the event that the widening is present in proximity to the outlet protuberance 39. The margins 32, 60 of the plates 4 are then parallel to one another as far as a zone in which a change takes place in the direction of flow of the coolant liquid.

The circuit 8 defined by the plates 4 makes it possible to guide the coolant liquid into a number n of successive passageways, in this case being two in number, in which the coolant liquid circulates from the inlet 40 towards the outlet 42. Two adjacent passageways are separated, for example, by the one or the plurality of central margins 60 of the plates 4. The passageways are arranged parallel to one another in an extension direction, in this case the large side of the plates 4. They can also be provided in series one after the other.

The circulation of the coolant liquid, changing its direction of flow from one passageway to the other, thus takes place in a direction that is generally perpendicular to that of the flow of the fluid to be cooled passing through the exchanger from the inlet surface of the array to its outlet surface, that is to say from one of the two large sides of the plates 4 to the other of the two large sides.

In the depicted example, where the plate 4 defines two passageways, the plate comprises a single central margin 60. It can also comprise half margins 60′, parallel to the central margin 60 and to the peripheral margins 32, in such a way as to divide a single passageway into a plurality of sub-passageways. The central margin 60 is thus oriented towards the large side of the plates 4 in order to define a serpentine circulation of the coolant liquid in each of the passageways of each of the circuits 8 for the circulation of the coolant liquid. The central margin 60 extends, for example, from the left-hand lateral edge 16 towards the right-hand lateral edge 17 of the plate, while leaving a passageway free to enable the coolant liquid to flow from the passageway present on one side of the central margin 60 to the other passageway present on the other side of the central margin 60.

The plate in this case comprises a number of baffles 55 situated inside the circuits 8. These baffles 55 arise, for example, from the material of the bottom of the plates 4, in particular by deep-drawing the plates. They may adopt a hemispherical shape, as illustrated in FIG. 2, or, for example, a more elongated shape.

Once assembled, the plates 4 are grouped together in pairs and in contact at the level of their flat surfaces 34, 46 and/or their margins 32, 60, 44. In this way, the circuit 8 of the upper plate and of the lower plate in one and the same pair of plates complement one another in order to constitute a circulation channel for the coolant liquid. The plates 4 are thus stacked by pairs, in such a way that the circuit 8 for the circulation of the coolant liquid of one of the two plates is situated opposite the circuit 8 for the circulation of the coolant liquid of the other of the two plates in one and the same pair, in order to form the circulation channel for coolant liquid.

In this way, the protuberances 38, 39 of the lower plate 4 of a pair of plate are situated opposite a number of protuberances 38, 39 of the upper plate 4 of the same pair of plate.

Returning now to the heat exchanger depicted in FIG. 1, it will be noted that the protuberances penetrate into the collector plate of the exchanger, in this case the left-hand wall 18 of the housing 5.

In order to cause the coolant liquid C to enter into and to exit from the circuits 8 of the various plates 4 of the exchanger 1, the latter comprises an inlet collection box 71 and an outlet collection box 72 for the coolant liquid C. The inlet collection box 71 is situated opposite a number of inlet protuberances 38 of the plates 4 and, together with a zone of the left-hand wall 18 at the level of which the inlet protuberances discharge, forms an inlet collector 73 for the coolant liquid C. In the same way, the outlet collection box 72 is situated opposite a number of outlet protuberances of the plates 4 and, together with a zone of the left-hand wall 18 at the level of which the outlet protuberances 39 discharge, forms an outlet collector 74 for the coolant liquid.

The collection boxes 71, 72 have the shape of a skirt that is open at the level of the left-hand wall 18 of the housing 5 in order to permit the coolant liquid C to enter into and/or to exit from the circuits 8 for the circulation of the coolant liquid by means of the protuberances. The collecting boxes 71, 72 likewise exhibit an opening, not illustrated here, in order to permit the coolant liquid C to enter into and/or to exit from the collectors 73, 74, that is to say to enter into and/or to exit from the exchanger 1.

The skirts in this case comprise two lateral surfaces 75, 76 situated to either side of protuberances and one surface, referred to as the left-hand surface 77, linking the two lateral surfaces 75, 76. It must be noted that lateral surfaces 75, 76 can exhibit forms that are flared from a lower or upper edge of the boxes towards an opposite surface that is provided with the inlet/outlet opening for the coolant fluid. In other words, the section of the skirts in a plane parallel to the plane in which the bottom of the plates 4 extends decreases from the upper surface as far as the lower surface.

The boxes 71, 72 are secured to the collector plate 18 by a distal contour, defined here by a folded edge 90 supported against said collector plate 18. Thanks to the flared form imparted to the circuit 8 in proximity to the protuberances, the boxes can be configured in such a way as to exhibit a width, that is to say a distance, between the two lateral surfaces 75, 76 of said boxes 71, 72, enabling the collector plate to exhibit a width, that is to say a distance, between the inlet/outlet surfaces for the fluid to be cooled, which width is substantially equal to, or slightly greater than, the length of the lateral edges of the plates 4.

The coolant liquid C thus penetrates into the exchanger 1 by entering into the inlet collector 73, for example by means of inlet/outlet tubes (not illustrated here). It is then distributed between the plates 4 in the circuits 8 for the circulation of the coolant liquid by means of the inlet protuberances. It then flows by doubling back into the two passageways of the circuits 8 for the circulation of the coolant liquid from the inlets into the outlets, at the level of which it exits from the array 2 before entering into the outlet collector 74. The coolant liquid C is then able to exit from the exchanger 1, for example via the inlet/outlet tubes.

FIG. 3 permits an aspect of the invention to be illustrated, according to which the left-hand wall 18 of the box 5, that is to say the collector plate, comprises a plane section 80 and collars 81 surrounding the protuberances 38, 39. Each collar 81 in this case comprises two protuberances 38, 39 in contact with one another and belonging to one and the same pair of plate. Their roles is to facilitate the insertion of the protuberances 38, 39 into the collector plate, in order to ensure their mechanical support and to guarantee the sealing between the inlet and/or outlet collectors and the array 2 for the exchange of heat for the cooling liquid and the fluid to be cooled. The collars 81 are produced by slotting the collector plate, for example, and are brazed to the protuberances 38, 39, in particular in a manner that is simultaneous with the brazing of the rest of the exchanger.

The collars 81 comprise an upper section 82 in contact with the protuberance 38, 39 of an upper plate of a pair of plate and a lower section 83 in contact with the protuberance 38, 39 of a lower plate of the same pair of plate. The lower and upper sections 82, 83 of the collars 81 are mutually symmetrical in relation to a plane passing through the flat surfaces 46 of the protuberances 38, 39.

Contact between the collars 81 and the protuberances takes place in particular at the level of the bottom 43 and the margins 44 of the protuberances 38, 39. The collars 81 in fact conform to an external surface of the margins 44 of the protuberances 38, 39 and to an external surface of the bottom 43 of the protuberances 38, 39.

The flat surfaces 46 of the protuberances 38, 39 are terminated at the level of a lateral surface 84. These lateral surfaces 84 are not in contact with the collars 81. In fact, the upper section 82 and the lower section 83 of the collars 81 are terminated at the level of the external surfaces of the flat surfaces 46 of the protuberances 38, 39 and do not surround the lateral surfaces of the flat surfaces 46. These lateral surfaces are thus directly in contact with the plane section 80 the collector plate.

FIG. 4 permits the illustration of the baffles 52 for the flow of the fluid to be cooled, which baffles extend between two adjacent pairs of plates. Thanks to the invention, these baffles 52 extend from one lateral wall of the box to the other. The left-hand lateral wall 18 in this case plays the role of a collector plate for the coolant liquid, and the baffles 52 are situated in proximity to the collector plate, that is to say at less than 1 mm from the collector plate. The exchange of heat is accordingly optimized, since it takes place in a zone extending from the left-hand lateral wall 18 of the box to the right-hand lateral wall of the box.

The different component parts of the exchanger are made of aluminum or an alloy of aluminum, for example. In particular, they are brazed to one another.

Claims

1. A plate for exchanging heat between a first and a second fluid circulating in contact with the plate, the plate configured to define a circuit for the first fluid, wherein the plate comprises one or a plurality of protuberances penetrating into a collector plate for the first fluid and defining an inlet into and/or an outlet from the circuit.

2. The plate as claimed in claim 1, comprising two protuberances respectively defining the inlet into and the outlet from the circuit.

3. The plate as claimed in claim 1, comprising two small sides and two large sides, such that the plate possesses the shape of a rectangle, the one or the plurality of protuberances being situated at a level of the small sides of the rectangle.

4. The plate as claimed in claim 1, wherein the plate and the one or the plurality of protuberances comprise a bottom and margins defining the circuit, the bottom of the one or the plurality of protuberances and the bottom of the plate extending in a plane.

5. The plate as claimed in claim 4, in which the margins delimiting the circuit are parallel to one another at the level of the one or the plurality of protuberances and the margins are flared out in a direction of the circuit (8).

6. An array for exchanging heat, the array comprising a stack of plates according to claim 1, the plates being arranged in pairs such that two plates of the same pair define a circulation channel for the first fluid.

7. A heat exchanger comprising the array for exchanging heat as claimed in claim 6 and the collector plate, penetrated by the one or the plurality of protuberances of the plates.

8. The heat exchanger as claimed in claim 7, comprising a housing provided with four walls and having an interior with the array disposed within the interior, and with the collector plate further defined as one of the four walls.

9. The heat exchanger as claimed in claim 7, comprising at least one inlet collector, into an interior of which the one or the plurality of protuberances of the plates defining the inlet into the circuits discharge, and one outlet collector, into an interior of which the one or the plurality of protuberances of the plates defining the outlet from the circuits discharge.

10. The heat exchanger as claimed in claim 7, in which the collector plate comprises a plane section and collars surrounding the one or the plurality of protuberances.

11. The heat exchanger as claimed in claim 10, wherein the one or the plurality of protuberances comprise margins terminating at a flat surface permitting brazing of the one or the plurality of protuberances to one another and the margins extending in a plane parallel to a plane in which the bottom of the one or the plurality of protuberances extends.

12. The heat exchanger as claimed in claim 11, in which two plates forming a pair of plates are in contact at a level of an internal surface of the flat surfaces.

13. The heat exchanger as claimed in claim 11, wherein the collars conform to an external surface of the margins of the one or the plurality of protuberances and an external surface of the bottom of the one or the plurality of protuberances and/or a lateral surface of the flat surfaces is in contact with the plane section of the collector plate.

14. The heat exchanger as claimed in claim 7, comprising baffles disposed therein, the baffles extending between two pairs of plates until the baffles are in proximity to the collector plate.

15. A module for admission of air comprising an exchanger according to claim 7.