FR3030029A1 - THERMAL EXCHANGE PLATE WITH MICROCHANNELS AND HEAT EXCHANGER COMPRISING AT LEAST ONE SUCH PLATE - Google Patents

Abstract

Heat exchange plate (2) for a heat exchange device between two fluids, said plate comprising strips (B1, B2) between two edges of the plates in a first direction (X), the strips (B1, B2) being arranged side by side in a second direction (Y), each band (B1, B2) having at least one fluid circulation channel extending from one edge to the other of the plate and opening into the edges of the the plate, said strips (B1, B2) having a corrugation comprising peaks and valleys, two directly adjacent strips being disposed relative to each other so that a vertex of a band and a vertex of the directly adjacent strip are offset in the first direction (X) and that, in the second direction (Y), the top of a strip and the hollow of the directly adjacent strip delimits the other fluid flow paths.

Description

TECHNICAL FIELD AND STATE OF THE PRIOR ART The present invention relates to a microchannel heat exchange plate and to a heat exchanger comprising at least one such heat exchanger plate. plate. The heat exchangers or heat exchangers with microchannels comprise an envelope provided with a plurality of micro channels in which a fluid circulates. The fluid may be in liquid and gaseous form changing phase, or the fluid is in liquid form or in gaseous form. The outer surface of the envelope exchanges heat with the external environment by convection. For example, an air circulation can evacuate or provide heat. The outer surface of the envelope is provided with fins to increase the exchange surface with the external environment. This type of exchanger is for example used in evaporators or condensers of mechanical machines with mechanical compression of refrigerant. The document US2011 / 0139420 describes an example of a microchannel heat exchanger intended to be implemented in an air conditioning device. The heat exchanger comprises flat tubes arranged parallel to each other, each tube having a plurality of microchannels. The microchannels are connected in parallel to a common power supply and to a common evacuation. The tubes are for example made of aluminum by extrusion. The tubes are twisted. Air circulates between the tubes. Fines are provided between the tubes to promote heat exchange with the air flowing between the tubes. Air circulates between the tubes and the fins; the presence of the fins causes a fouling of the passages between the tubes and the fins and the occurrence of a pressure drop within the device and therefore a drop in efficiency of the heat exchange device.

In addition, this device has many parts to manage and assemble. In addition the thermal connections between the tubes and the fins are difficult to achieve in order to obtain a good thermal connection between the tubes and the fins. The manufacturing cost of this device is therefore high.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a heat exchange plate and a microchannel heat exchange device in which the disadvantages mentioned above are reduced. The object of the present invention is achieved by a microchannel heat exchange plate having parallel strips, each strip having at least one microchannel extending from one end to the other of the strips and opening into said ends, a first fluid being intended to flow in said microchannels, each of the strips having a corrugation, the relative arrangement of the strips being such that the corrugations of the strips define in a direction parallel to the plate and secant to the direction of the strips of the flow paths a second fluid. The plate does not require the use of fins, the manufacture can be significantly simplified. In addition, fouling problems are reduced which allows to maintain a certain level of efficiency. Furthermore, the corrugations of the strips create a favorable tortuosity for the heat exchange between the first fluid flowing in the microchannels and the plate, in addition, they generate a large heat exchange surface between the plate and the second fluid. In other words, the heat exchange plate comprises microchannels for a first fluid, the plate being shaped so as to define virtual channels for circulation of a second fluid in a secant direction to those of the channels. The presence of flow paths extending from a secant direction to that of the microchannels ensures a high flow of air with a low pressure drop while ensuring the existence of obstacles between the virtual channels, these obstacles allow to break the boundary layers on the structure, causing the appearance of turbulence beneficial to the development of convective heat exchange coefficient on the surface of the plate. According to the invention, the device comprising at least one heat exchange plate 5 has a very high heat exchange compactness in terms of square meter of primary exchange surface reduced to the volume of the structure. In a particularly advantageous manner, the device comprises several stacked plates. New virtual channels are then defined between the bands of the plates that intersect. Depending on the orientation of the plates relative to each other and the distance between the plates, it is possible to very easily adapt the heat exchanger to the operating conditions of the exchangers and to the required compactness. Indeed, the section of the flow paths can be varied easily, changing the pressure drop across the stack and the size of the stack.

Very advantageously, spacers are integrated with the plates to fix the distance between the plates. The present invention therefore relates to a heat exchange plate for a heat exchange device between a first fluid and a second fluid, said heat exchange plate extending in a plane, said heat exchange plate comprising at least one heat exchange plate. minus two strips extending between a first edge of the heat exchange plate and a second edge of the heat exchange plate opposite the first edge in a first direction, the strips being arranged next to each other in a second direction, each of the strips having at least one channel extending from the first edge to the second edge and opening into the first edge and the second edge, said channel being intended for the circulation of a first fluid, said strips having each an undulation comprising vertices and valleys, two directly adjacent bands being relatively arranged relative to one another such that a vertex of a band and a vertex of the directly adjacent strip are offset in the first direction and such that, in the second direction, the vertex of one strip and the hollow of the directly adjacent strip delimits traffic paths of a second fluid. The second fluid circulating outside the bands and transversely thereto. Preferably, each band has several channels.

For example, the strips have a thickness of between 0.5 and 10 mm and the channels have a hydraulic diameter of between 0.5 mm and 10 mm. Preferably, the vertices are located on one side of the plane of the heat exchange plate and the recesses are located on the other side of the plane of the heat exchange plate.

The present invention also relates to a heat exchange device comprising at least one heat exchange plate according to the invention, at least one supply manifold in a first fluid connected to the channels at the first edge of the plate. heat exchanger and at least one exhaust collector connected to the channels at the second edge (6) of the heat exchange plate 15. In an exemplary embodiment, the heat exchange plate is wound on itself in spiral form. The subject of the present invention is also a heat exchange device comprising at least two thermal exchange plates according to the invention, at least one supply manifold in a first fluid connected to the channels at at least a first edge of at least one heat exchange plate and at least one exhaust manifold connected to the channels at at least one a second edge of at least one heat exchange plate, said heat exchange plates being stacked so that the peaks and troughs of the strips delimit between them the circulation paths of the second fluid. In an exemplary embodiment, the heat exchange plates are identical and are oriented relative to each other so that the strips of a heat exchange plate are located at least partly between the strips of the heat exchange plate. other heat exchange plate.

In another embodiment, the heat exchange plates are identical and are oriented relative to each other so that each vertex of a heat exchange plate bears against a hollow of the other heat exchange plate.

The heat exchange plates may be joined to each other by welding points at a hollow and an apex, two vertices or two recesses. The heat exchange device may comprise spacer means fixing the distance between two successive plates.

In an advantageous example, the spacer elements are formed by the soldering points. In another example, the plates are bent and are arranged relative to each other about an axis so that the device has a symmetry of revolution.

In a very advantageous example, the heat exchange plate (s) is (are) manufactured by extrusion and forming. The heat exchange plates can be made from strips made individually and then secured to each other, the spacer elements being interposed between strips when they are secured.

Each spacer element may then comprise a strip and at least one projection forming a spacer, said strip being secured to the heat exchange strips. The projection may be a tongue cut in the band and folded. Advantageously, the tongue has a free end comprising a flap intended to be secured to an adjacent plate.

According to another example, the heat exchange plates are made from a plate grooved between two solid plates, the spacer elements being made in one piece with said stack by cutting and deformation.

The present invention also relates to a method of manufacturing a heat exchange plate comprising the steps of: a) extrusion of plates with channels, b) shaping of the plate so that it comprises adjacent strips 5 each having a given undulation. The present invention also relates to a method of manufacturing a heat exchange plate comprising the steps a ') manufacturing a plate provided with parallel slots, the slots passing through a plate thickness and two solid plates, the three plates having the same surface, b ') stacking of the three plates so that the plate provided with slots is arranged between the two solid plates and securing the three plates, c') cutting the edges of the plate provided with the slots so that the slots open towards the outside of the stack at their two ends, the channels being delimited by the slots and the solid plates, d) making cutting between the channels so as to delimit strips, e ') deformation of the bands so as to give them a given undulation.

The present invention also relates to a method of manufacturing a heat exchange device comprising at least one heat exchange plate comprising steps A) production of a plate according to the method according to the invention, B) connection first ends of the channels at a manifold and second ends of the channels at another manifold. The present invention also relates to a method of manufacturing a heat exchange device comprising at least two heat exchange plates comprising steps A ') producing at least two plates according to the invention, B') stacking the heat exchange plates, 3030029 7 C ') connecting the first ends of the channels of at least one plate to at least one collector and second ends of the channels of at least one plate to at least one other collector. In one example, the two plates may be identical and may be stacked so that the strips of one plate are located at least partly between the strips of the other plate. According to another example, the two plates may be identical and may be oriented relative to each other so that each vertex of one plate bears against a hollow of the other plate.

During step A ') spacer elements are for example made by cutting and folding the plates. In step A ') strips having at least one projecting portion intended to abut against another plate may be interposed between bands provided with channels.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood on the basis of the following description and the appended drawings in which: FIG. 1 is a perspective view of an exemplary embodiment of an exchange device Figure 2A is a perspective view of the plate of the device of Figure 1 shown alone; Figure 2B is a side view of the plate of Figure 2A; FIG. 3 is a side view of another exemplary embodiment of a heat exchange plate, FIGS. 4A and 4B are diagrammatic representations of two steps for producing a heat exchange plate in accordance with FIG. second technique, - Figure 4C is a cross-sectional view of an alternative embodiment of a heat exchange plate according to the second technique, - Figure 4D is a perspective view of a single strip in the case of a salt manufacture a variant of the first technique, - Figure 5 is a perspective view of an embodiment of a heat exchange device having a plurality of heat exchange plates 5 arranged relative to each other in a first configuration Fig. 6A is a perspective view of the plates of the device of Fig. 5; Fig. 6B is a side view of the stack of Fig. 6A; Figs. 7A through 7F are side views of Fig. 6A; FIG. 8A is a perspective view of a stack of heat exchange plates in a second configuration, FIG. 8B is a side view of the stack of FIG. FIG. 8A; FIG. 9 is a perspective view of a practical embodiment of a heat exchange device of FIG. 5; FIG. 10A is a side view of a stack of plates according to the first configuration with elements of spacer according to a first exemplary embodiment, - Figure 10B is a side view of a stack of plates according to the second configuration having spacer elements according to a first embodiment, - Figure 11A is a perspective view a stack of plates according to the first configuration having spacer elements according to a second embodiment, - Fig. 11B is a detail view of Fig. 11A, - Fig. 11C is a perspective view of a spacer element used in the stack of FIG. 11A shown alone; FIG. 12A is a perspective view of a stack of plates according to the second configuration comprising spacer elements according to a third embodiment, 3030029 FIG. 12B is a detail view of FIG. 12A; FIG. 13 is a perspective view of an exemplary embodiment of a heat exchange device having a symmetrical pattern; FIG. FIG. 14 is a perspective view of an exemplary embodiment of a heat exchange device comprising a spiral wound plate on itself, FIG. 15 is a side view of FIG. a strip of a heat exchange plate on which dimensions are carried. DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS In FIG. 1, an example of a heat exchange device D1 according to the invention can be seen and in FIGS. 2A and 2B a part of this device can be seen in perspective and in view side respectively. The heat exchange device of FIG. 1 comprises a heat exchange plate 2 extending substantially in a plane P.

The plate 2 comprises a plurality of strips B1, B2 ..., each strip B1, B2 is substantially rectilinear and extends along a longitudinal direction X. Each strip (see FIG. 4D) has a length L along of the direction X, a width I along a direction Y perpendicular to the direction X and contained in the plane P and a thickness e in a direction perpendicular to the plane P.

The strips B are arranged next to one another in the Y direction and are integral with one another. Each strip comprises at least one microchannel (not shown) extending in the X direction and opening into first and second longitudinal ends 4, 6 of the strips, forming the edges of the plates.

In the present application, the term "microchannel" means a channel whose hydraulic diameter is between 0.5 mm and 10 mm. Preferably, each band has a plurality of parallel microchannels distributed along the Y direction.

Each band has a corrugation from its first longitudinal end 4 to its second longitudinal end 6. Preferably this corrugation is periodic. The corrugations of the strips and the relative arrangement are so selected that, in considering the Y direction, preferred flow paths C1, C2, ... for a second fluid between the bands are defined by all the bands and between the bands. This is particularly visible in Figure 2B. Preferably, all the strips have the same corrugation, but the corrugations of two adjacent strips are out of phase, advantageously the phase shift is such that a recess 7 of one strip is aligned with a vertex 9 of the adjacent band in the Y direction. Thus flow paths of maximum section are delimited. A plate in which the depressions and the vertices are not aligned along the Y direction is not outside the scope of the present invention.

In the example shown, the general profile of the undulation of the bands is a sinusoidal curve. It can be expected that the undulation of the strips is exactly a sinusoidal curve. In this case, preferably, the bands have the same undulation and two adjacent bands are out of phase of n. The device also comprises a supply manifold 8 connected to one end of the microchannels and intended to supply the microchannels with a first fluid and an evacuation manifold 10 connected to the other end of the microchannels and intended to collect the first outgoing fluid. microchannels. Preferably, each strip has at its ends, into which the microchannels open, planar portions 11, 13 contained in the plane P. Thus, all the microchannels open into the plane P at both ends of the plate facilitating the connection of the microchannels to the 8 and discharge manifolds 10. Preferably, all microchannels are connected to the same supply and discharge manifolds simplifying the manufacture of the device. However, it could be provided to feed the microchannels of each band separately from the other bands, or even to feed each microchannel individually. Similar configurations can be applied to microchannel evacuation. In FIG. 3, another example of a plate seen from the side along the Y direction can be seen. In this example, each strip has a corrugation such that it is located on one side only of the plane P, two strips. successive B1 ', B2' being located on both sides of the plane P. We can see the preferred flow paths C1 ', C2'. The fluid flowing in the plates is for example a liquid, a gas or a liquid / gas mixture. The fluid flowing in the direction Y is for example a gas or a mixture of gases such as air or a liquid. It can be envisaged that the plate is arranged in a housing in which a circulation of liquid is established. The operation of the heat exchange device will now be described. A first fluid is circulated in the microchannels via the supply and discharge manifolds, the supply manifold being connected to a source of first fluid and the exhaust manifold being connected for example to a storage area. of this first fluid. A pump is for example implemented to ensure the circulation of the first fluid. The exhaust manifold may be connected to the supply manifold to circulate the first fluid in a closed loop in the plates. Simultaneously, the second fluid, for example air, circulates between the strips of plates, for example by forced convection by means of a fan. The first fluid convectively exchanges with the material of the bands and the bands exchange by convection with the air.

Due to the tortuosity of the microchannels, the heat exchanges are favored between the first fluid and the material of the strips. Due to the very large surface of heat exchange, the exchanges between the air and the bands are favored. In addition, the pressure drops are low for the second fluid ensuring a significant air flow.

3030029 12 The device allows very efficient heat exchange in a small footprint. The plate can be made according to different techniques. According to a first technique, a multiport plate is made directly by extrusion, spaces being provided between the channels thus defining strips. The embossing or the shaping of the strips is then carried out so as to present the desired profile. As indicated above in relation to the first technique, the section of the patterns may be square, rectangular, cylindrical, semi-cylindrical, rhombic, triangular, ovoid, etc. In a variant, strips such as the B1 band are individually produced. represented in FIG. 4D, for example by extrusion. The channels are made during extrusion. In FIG. 4D, one can see one of the ends 19 of the channels. The strips B1 are then shaped so that they have a ripple. The strips B1 are then assembled, for example by welding, so that the hollow areas of two successive bands are offset in the Y direction. The plates 2 are preferably of rectangular or square shape, the strips may extend in length. or in the width of the plates. In FIGS. 4A and 4B, an example of a second technique for manufacturing the plate of the heat exchanger device 2 can be seen. On the one hand, a rectangular or square plate 10 with slots extending perpendicular to two 10.1, 10.2 of its edges. The slots pass through the plate in its thickness but do not open into the edges 10.1, 10.2 of the plate 10. The slots 12 are for example made by stamping, laser cutting or chemical etching. Two full plates 14, 16 having the same external dimensions as the plate 10 are also produced. The plate 10 is placed between the two solid plates 14 and 16 and the three plates 10, 14, 16 are then assembled so that the slots delimit with the inner faces of the plates 14, 16 sealed microchannels. In the example shown, the channels have a square or rectangular section but other sections are conceivable, for example a cylindrical or semi-cylindrical section. Alternatively, the plate 10 may be formed of two superimposed plates each comprising a portion of the section of the channels, which allows for the production of channels having more complex sections, for example a rhombic, triangular, ovoid section ...

On the other hand, in the example shown, the slots are rectilinear, but one could predict that they have a sinuous profile, making it possible to improve the exchange coefficient. It could also be envisaged that the channels are not all the same. profile.

The plates 10, 14 and 16 are then assembled preferably by brazing, welding or molecular diffusion is also possible. The edges 10.1, 10.2 of the plate 12 are then pierced with orifices 17, for example by machining right of the slots 12 so as to open the microchannels outwards as shown in Figure 4B.

In a next step, through cuts are made in the thickness of the stack between the microchannels, thus delimiting strips B1, B2. During a following step, each band B1, B2 is deformed individually. to give it the desired profile by applying transverse forces to the plane of the stack. The cuts between the channels are advantageously discontinuous so that the strips remain interdependent with each other. As a variant of this second technique, the assembly can be made using two plates (FIG. 4C): a first plate 110 in which grooves are made for example by chemical etching, laser etching, machining, stamping, etc. and a second closure plate 112. The two plates thus assembled delimit the 25 channels. In Figure 5, we can see an example of a heat exchange device D2 implementing several plates such as that shown in Figure 2A. The use of several heat exchange plates is very advantageous because it makes it possible to have a very compact device in terms of heat exchange.

The device of FIG. 5 comprises a stack of plates 2, a supply manifold 108 supplying all the plates in parallel and an evacuation collector 110 connected to all the plates. Alternatively one could provide individual collectors for each plate or collectors common to a group of 5 plates. It is also conceivable to circulate several times the first fluid in the same plate, the first fluid for example using channels to make a go and other channels to make a return. It can also be envisaged to circulate the fluid from one plate to the other in a stack of 10 plates. The plates can have any orientation, for example horizontal or vertical, denotes the assembly formed by the plates arranged next to each other or on each other by "stacking". In Figures 6A and 6B, one can see the stack of plates alone. In this example eight plates 2 are stacked. In the configuration of Figures 6A and 6B, the plates 2 have the same orientation, so that the plates fit into each other. The plates define between them new preferred flow paths for the flow of air in the Y direction.

By varying the distance between the plates 2, the section of the privileged paths is modified. The size of the stack is then easily modified to adapt to the requirements of heat exchange and compactness. In Figs. 7A-7F, different stacks may be seen in the first configuration, the plates being increasingly spaced from each other from Fig. 7A to Fig. 7F. The distance between the end of the plates is designated E. It is found that thanks to the structure of the plates, it is very easy to modify the "porosity" of the stack, ie the section of the privileged paths, and thus to modify the characteristics of the heat exchange device.

For example, it can be seen that the stack of FIG. 7A has the advantage of being very compact but that the crossing sections of the privileged paths are reduced, the pressure drops are then greater. The stack of FIG. 7F is more bulky but has important air passage sections, so the efficiency of the device is increased. A heat exchange device in which the distance between the plates would not be constant does not depart from the scope of the present invention. The device according to the invention thus offers great adaptability to the conditions of space and efficiency and this in a very simple manner without having to modify the structure of the plates. In Figures 8A and 8B, another configuration can be seen in which the plates have inverted configurations, i.e. the plates are arranged back to back. If we consider that the plates 2 have a bottom face 2.1 provided with recesses and an upper face 2.2 provided with vertices, whatever their orientation, the plates are superimposed so that each plate, with the exception of the end plates lower and upper, has its lower face in front of a lower face of the plate located on one side and its upper face opposite the upper face of the plate on the other side. There is then a plane of symmetry between the successive plates. The tops and hollows of the plates are then in contact, the plates not fitting into each other. This configuration has the advantage of offering a self-supporting stack and privileged flow paths of constant passage sections. Alternatively, it can be envisaged in the second configuration that the plates are not in contact with each other.

FIG. 9 shows an exemplary practical embodiment of a heat exchange device D3 comprising a stack of plates 2. The stack is received in a frame 18 comprising two lateral uprights 20 connecting two lower and upper crosspieces. 21. The ends of plates in which the microchannels 30 open are fixed to the lateral uprights 20. The lateral uprights 20 are provided with through-holes 23 at the openings of the microchannels to allow their connection to a circulation circuit of the first fluid ( not shown). The air flows between the crosspieces 21 and the uprights 20. In this example, the stack has the first configuration.

When the plates are of sufficiently short length not to exhibit significant bending, they may be supported only at their longitudinal ends. On the other hand, when the plates are of such a length that the plates can bend under their weight, spacer means are provided between the plates to provide support and prevent bending. These means relieve the plates of possible thermomechanical and vibratory stresses. In Figures 10A and 10B, we can see an embodiment of these means forming spacers, it is welding points 22 made between the successive plates. These weld points 22 further ensure a securing of the plates together and the realization of a stack in one piece. FIG. 10A represents a stack according to the first configuration, the soldering points 22 connect two peaks of the corrugations of plates. FIG. 10B shows a stack according to the second configuration, the soldering points 22 connecting an apex 9 of a plate and a recess 7 of another plate.

The welding points advantageously prolong the heat exchange surfaces of the plates, and are interposed in the air stream, in particular in the stack of FIG. 10A. The heat exchange efficiency of the device is therefore advantageously increased. According to another exemplary embodiment, add-on elements forming spacers are provided. In FIGS. 11A and 11B, one can see a stack of plates provided with such elements according to an exemplary embodiment. In Fig. 11C, element 24 is shown alone. The spacer elements 24, in the example shown, are arranged between two strips B1, B2 ... It comprises a strip 26 of length equal to the strips B1, B2 and comprise at least 3030029 17 one on one side of the strip and defining the spacing between the plates 2. In the example shown, each strip has two projections 25. In addition, particularly advantageously, each projection 25 is formed by a tongue 28 cut in the strip and folded so as to projecting from one side of the web 26. The construction of the spacer elements is thus simplified and their mass is reduced. Alternatively, one could consider reporting on the band a stud forming the projection, in this case the mass of the element would be increased. This embodiment has the advantage of allowing the same spacer elements to be used for different spacings between the plates since it is sufficient to fold the tabs more or less to modify the spacing. They can therefore be used either to produce different devices each having their own distance between plates or to make a single device having different distances between the plates. The manufacturing cost can be reduced. In the example of FIG. 11A, the plates of the stack are made from strips shaped individually and then assembled. When assembling the strips, the spacer elements 24 are interposed between two bands, the strips B1, B2,... Being secured by their lateral edges to the spacer elements 24. In FIG. detail view of the stack of FIG. 11A. The stack corresponds to that of the first configuration. In the example shown, all the spacer elements 24 are identical, the plates 2 are then stacked so that the tongues 28 of two successive plates 2 are intersecting and non-parallel, the tongues 28 of the spacer elements 24 of the neighboring plate then rest on an unfolded area of the strip 26.

Alternatively, it can be provided that the spacer elements are not identical from one plate to another. It could for example be provided that the distance between two tongues 28 is different from one plate to another so the plates could be stacked so that the tabs have the same orientation. Very advantageously, the tabs are shaped to allow them to be secured to the plate against which they are supported. For example, their free end 28.1 is folded so as to have a flange 30 bearing flatly against the plate below or above, for example on a flat area of the strip 26 in the example of FIGS. 11A and 11B . The plate 30 is for example secured to the other plate by diffusion welding or brazing.

In the example shown, spacer members 24 are provided in each pair of strips B1, B2 ... but it could be provided to dispose of all or more of them. Each plate comprises at least two spacer elements 24. It will be understood that any form of spacer element may be suitable. In the example described, all the plates comprise spacer elements, all the spacer elements being oriented towards the top plate or the bottom plate. Alternatively, it could be expected that every other plate in the stack comprises spacer elements, the tabs 28 being oriented alternately to the top plate and to the bottom plate. Strips having the same dimensions as the spacer elements are provided between the strips B1, B2 ... 15 in the plates having no spacer elements in order to maintain the geometry of the stack. In FIGS. 12A and 12B, another example embodiment of plates provided with spacer elements more particularly adapted to the production of a plate according to the second embodiment technique described above can be seen.

In this example, the spacer members 124 are formed directly in the stack between the microchannels by cutting, stamping, and folding. In the example shown, the spacer elements 124 are hook-shaped, the free end of the hook advantageously having a flange 130 for attachment to the adjacent plate by welding, diffusion or brazing.

Alternatively, the spacer members 124 could have a tongue shape similar to that of FIGS. 11A-11C. It would be possible to individually fix tabs or any projecting piece directly on the lower or upper faces of the strips B1, B2. In the examples shown, the spacer elements 24, 124 are advantageously integrated with the plates, simplifying the carrying out the stacking. But a device in which the elements ensuring spacing between the plates would be independent of the plates are not beyond the scope of the present invention, for example in the case of the device of Figure 9, it is conceivable that rods forming a support are fixed between the two lateral uprights, the plates resting on the rods. The distance between two successive rods in the vertical direction fixes the spacing between two plates. In Figure 13, we can see another embodiment of a heat exchange device comprising a plurality of heat exchange plates.

In this example, the plates are bent and are arranged around an axis Y1 so as to form a device having a symmetry of revolution. Each plate 2 comprises a collector 208, 210 at each end of the channels. The plates are mounted so that one of the connectors 208 is located radially inside the exchanger and the other collector 210 is disposed radially outside the device. For example, the supply manifolds 208 are radially inside and are connected to a common supply manifold (not visible) for example at one of their ends and the exhaust manifolds 210 are radially outwardly and are connected to a common evacuation collector 212, for example at one of their ends. In the example shown, the common evacuation collector 212 has the shape of a ring. The central common manifold could be formed of a tube filling the entire central portion of the collector. The circulation of the air is symbolized by the arrows F. It circulates along the axis of symmetry Y1 of the device. It can be provided a fan for example in the center of the device for moving the air by forced convection. In Figure 14, we can see another embodiment shown schematically of a heat exchange device comprising a single plate. The plate is wound so as to form a spiral. The self-wound plate 3030029 functionally forms a stack comparable to those of FIGS. 7A-7F. The plates of the exchanger are advantageously made of materials with very good thermal conductivity.

When the plates are made from a stack of sheets, they may for example be made of black steel, stainless steel, aluminum alloy and / or copper. In general, the plates can be made of any metallic material that can be assembled by brazing, soldering-diffusion, bonding, soldering, solder-diffusion, ultrasonic welding, friction welding ("stir welding" in English terminology). , laser beam welding, electron beam welding. When the sheets are made of polymer, we can use any type of thermoplastic polymer that can be assembled for example by gluing, ultrasonic welding, friction welding, high frequency welding, mirror welding, laser welding. Fillers such as, for example, carbon, boron nitride, glass or carbon fibers, carbon nanotubes may be incorporated into the polymers to improve their thermal conductivity and mechanical strength properties. Alternatively, provision may be made to insert into the stack of uncharged polymer sheets a sheet of material having high thermal and / or mechanical properties such as, for example, a pyrolytic carbon sheet, a fabric or a mat of glass, carbon ... to obtain improved thermal and / or mechanical properties.

When the plates are made by extrusion, they may be made of any material capable of being extruded and preferably having good thermal conductivity, such as metallic materials such as aluminum alloys, copper alloys or any other material which can be extruded. be implemented by extrusion, such as ceramic or charged polymer. Different types of polymer are possible, for example PVDF (polyvinylidene fluoride), PPO (polyphenylene oxide), PP (polypropylene), CPVC (polychlorinated vinylchloride), PA (polyamide), PPS (Polysulfide Phenylene), PEI (Polyetherimide), PSU (Polysulfone), PBI (Polybenzidimazole), PFA (Perfluoroalkoxy), PEEK (Polyetheretherketone), PMMA (Polymethacrylate Methyl). for example, carbon, boron nitride, glass or carbon fibers, carbon nanotubes may be incorporated into the polymer to improve its thermal conductivity and / or mechanical strength properties. The same materials are conceivable when the plates are made by assembling strips made individually, then assembled between them. As an example only considering the dimensions indicated in FIG. 4D and in FIG. 15, we will give an example of dimensions. relating to a band. The thickness e is preferably greater than or equal to 0.5 mm.

The height h of the web, i.e. the distance between a trough and a vertex is greater than or equal to 1.5xe. The width I of the band is for example greater than 1.5xe. The pitch p is preferably greater than 3xe. The angle α which represents the inclination of a corrugation with respect to the horizontal is preferably between 10 ° and 80 ° in the representation. The radius t of a vertex or a hollow is preferably greater than or equal to 3xe. The length L of a band can be any. By way of example only, a strip has the following dimensions: 25 e = 2 mm; I = 20 mm; L = 250 mm; a = 30 °; a radius t = 8mm; h = 20 mm. The heat exchange plate and the heat exchange device according to the invention have the following advantages: They are of relatively simple construction, use few parts. This results in a reduced manufacturing cost compared to the plates and devices of the state of the art.

3030029 22 They are robust and offer good reliability due to the limited number of assembled parts. They offer good thermal performance. Indeed, the flow of the fluids in the plates is tortuous which improves the exchange coefficient between the plate and the fluid, which is particularly interesting in the case of fluid having poor thermal conductivity such as oils. .. In addition, especially in the case where a single plate is implemented, the device offers an aesthetic appearance also allowing it to serve as an architectural element, for example on a facade or on a roof while ensuring its 10 role of heat exchanger. The heat exchanger according to the invention can be applied for example to produce a radiator-type gas / liquid exchanger, a liquid / liquid exchanger, an evaporator or a condenser, exchanger arranged on the wall of a building, a type exchanger natural convection radiator, an on-board liquid / gas exchanger 15 for aeronautics and aerospace ...

Claims (27)

REVENDICATIONS1. Heat exchange plate (2) for a heat exchange device between a first fluid and a second fluid, said heat exchange plate extending in a plane (P), said heat exchange plate (2) comprising at least one at least two strips (B1, B2) extending between a first edge (4) of the heat exchange plate (2) and a second edge (6) of the heat exchange plate (2) opposite to the first edge ( 4) in a first direction (X), the strips (B1, B2) being arranged next to each other in a second direction (Y), each of the strips (B1, B2) comprising at least one channel extending from the first edge (4) to the second edge (6) and opening into the first edge (4) and the second edge (6), said channel being intended for the circulation of a first fluid, said strips (B1, B2 ) each having a corrugation comprising vertices (9) and recesses (7), two directly adjacent strips being relatively relatively to each other other such that a vertex (9) of a band and an apex (9) of the directly adjacent band are offset in the first direction (X) and so that, in the second direction (Y), the vertex (9) of a band and the hollow (7) of the directly adjacent band delimits circulation paths (C1, C2, C1 ', C2') of a second fluid. 2. heat exchange plate according to claim 1, wherein each band (B1, B2) comprises several channels. 3. Heat exchange plate according to claim 1 or 2, wherein the strips (B1, B2) have a thickness of between 0.5 and 10 mm and the channels have a hydraulic diameter of between 0.5 mm and 10 mm. 4. heat exchange plate according to one of claims 1 to 3, wherein the vertices (9) are located on one side of the plane (P) of the heat exchange plate (2) and the recesses (7). ) are located on the other side of the plane of the heat exchange plate (2). 3030029 24 5. Heat exchange device comprising at least one heat exchange plate (2) according to one of claims 1 to 4, at least one supply manifold (8) in a first fluid connected to the channels at the first level. edge (4) of the heat exchange plate (2) and at least one discharge collector (10) connected to the channels at the second edge (6) of the heat exchange plate (2). 6. Heat exchange device according to claim 5, wherein the heat exchange plate (2) is wound on itself as a spiral. 7. Heat exchange device comprising at least two heat exchange plates (2) according to one of claims 1 to 4, at least one supply manifold (108) in a first fluid connected to the channels at the level of at least one first edge (4) of at least one heat exchange plate (2) and at least one exhaust manifold (110) connected to the channels at at least one second edge (6) of at least one heat exchange plate (2), said heat exchange plates (2) being stacked so that the vertices (9) and the hollow (7) of the strips delimit between them circulation paths of the second fluid. 20 8. Heat exchange device according to claim 7, wherein the heat exchange plates (2) are identical and are oriented relative to each other so that the strips (B1, B2) of a heat exchange plate are located at least partly between the strips (B1, B2) of the other heat exchange plate. 9. Heat exchange device according to claim 7, wherein the heat exchange plates (2) are identical and are oriented relative to each other so that each vertex (9) of a plate of heat exchange is in abutment against a hollow (7) of the other heat exchange plate. 3030029 25 10. Heat exchange device according to one of claims 7 to 9, wherein the heat exchange plates are secured together by welding points (22) at a hollow (7) and a vertex (9), two vertices (9) or two recesses (7). 5 11. Heat exchange device according to one of claims 7 to 10, comprising spacer means fixing the distance between two successive plates. 10 12. Heat exchange device according to claims 10 and 11, wherein the spacer elements are formed by the weld points (22). 13. Heat exchange device according to one of claims 5 to 12, wherein the heat exchange plate or plates is or are manufactured by extrusion and shaped. 14. Heat exchange device according to claims 11 and 13, wherein the heat exchange plates are manufactured from strips made individually and then secured to each other, the spacer elements 20 (24) being interposed between bands during their joining. 15. Heat exchange device according to the preceding claim, wherein each spacer element (24) comprises a strip (26) and at least one projection (25) forming a spacer, said strip (26) being secured to the strips 25. heat exchange. 16. A heat exchange device according to the preceding claim wherein the projection is a tongue (28) cut in the band and folded. 3030029 26 17. Heat exchange device according to the preceding claim, wherein the tongue (28) has a free end (28.1) comprising a flange (30) intended to be secured to an adjacent plate. 5 18. Heat exchange device according to one of claims 7 to 12, wherein the heat exchange plates are made from a grooved plate (10) between two solid plates (14, 16), the elements of spacer (124) being formed integrally with said stack by cutting and deformation. 10 19. Heat exchange device according to one of claims 7 to 18, wherein the plates 202 are bent and are arranged relative to each other about an axis (Y1) so that the device has a symmetry of revolution. 15 20. A method of manufacturing a heat exchange plate according to one of claims 1 to 4, comprising the steps of: a) extrusion of plates with channels, b) shaping of the plate so that it comprises adjacent strips each having a given undulation. 20 21. A method of manufacturing a heat exchange plate according to one of claims 1 to 4, comprising the steps: a ') manufacturing a plate (10) provided with slots (12) parallel, the slots (12) ) passing through a plate thickness and two solid plates (14, 16), the three plates (10, 14, 16) having the same surface, b ') stacking the three plates (10, 14, 16) so that the plate (10) provided with the slots (12) is arranged between the two solid plates (14, 16) and secures the three plates (10, 14, 16), 3030029 27 c ') cuts the edges of the plate (10) provided with the slots (12) so that the slots (12) open outwardly of the stack at their two ends, channels being delimited by the slots and the solid plates, d ') embodiment of cutting between the channels so as to delimit bands, e ') deformation of the bands so as to give them a given undulation. 22. A method of manufacturing a heat exchange device 10 comprising at least one heat exchange plate comprising steps A) producing a plate according to the method of claim 20 or claim 21 B) connection of the first ends of the channels to a collector and second ends of the channels to another collector. 15 23. A method of manufacturing a heat exchange device comprising at least two heat exchange plates comprising steps A ') producing at least two plates according to the method of claim 20 or claim 21, 20 B ') stacking the heat exchange plates, C') connecting the first ends of the channels of at least one plate to at least one collector and second ends of the channels of at least one plate to at least one other collector. 25 24. The manufacturing method according to the preceding claim, wherein the two plates are identical and are stacked so that the strips of a plate are located at least partly between the strips of the other plate. 3030029 28 25. The manufacturing method according to claim 23, wherein the plates are identical and are oriented relative to each other so that each vertex of a plate bears against the hollows of the other plate. 5 26. The manufacturing method according to claim 23, wherein in step A ') spacer elements are made by cutting and folding plates. 27. The manufacturing method according to claim 23, wherein in step A ') strips having at least one projecting portion intended to abut against another plate are interposed between bands provided with channels.