Heat exchanger comprising a plurality of stacked plates

Abstract

Heat exchanger comprising a plurality of stacked plates The invention relates to a heat exchange device (100) configured to allow the exchange between a first and a second heat transfer fluid, said device (100) comprising a bundle (200) of plates stacked on top of each other to form between each plate a channel (1, 2) in which one or other of the heat transfer fluids circulates, each plate of the bundle (200) comprising a distribution zone (3) comprising means for distributing (31) the first or second heat transfer fluids, a collection zone (4) comprising means for recovering (41) the first or second heat transfer fluids and a flow zone (5) between the distribution zone (3) and the collection zone (4),characterized in that the channels (1) of the first fluid comprise at the junction between the distribution zone (3) and the flow zone fluid restriction means (6) configured to homogenize a liquid phase and a gaseous phase of the first fluid when the first fluid enters the flow zone (5). [Figure 2],

Description

Title of the invention: Heat exchanger comprising a plurality of stacked plates Technical field

[0001] The present invention relates to a heat exchange device comprising a plurality of stacked plates. Prior art

[0002] In the automotive field, it is common to have to modify a temperature of an element, such as an electric motor, a battery, a device for storing calories and / or frigories or the like. For this purpose, the motor vehicle is equipped with an installation which comprises a circuit of a first fluid such as for example a refrigerant fluid inside which this first fluid circulates and a second circuit of heat transfer fluid inside which a second heat transfer fluid circulates. In the case of a refrigerant fluid, the circuit of said refrigerant fluid comprises a compressor for compressing the refrigerant fluid, a heat exchanger for cooling the refrigerant fluid at constant pressure, an expansion member for allowing expansion of the refrigerant fluid and a heat exchange device which is arranged to allow heat transfer between the refrigerant fluid and the heat transfer fluid.

[0003] The heat exchange device is an exchanger formed of plates stacked and joined together to form tubes delimiting circulation channels of the first fluid, for example refrigerant, or of the second heat transfer fluid.

[0004] It is common for one of the fluids entering the heat exchanger to have a two-phase state and to be a mixture of a liquid phase and a gaseous phase. The presence of these two phases at the inlet of the heat exchange device results in poor distribution of the fluid within the channels. Significant temperature gradients then appear in the volume of the heat exchange device, significantly reducing the thermal power of the latter.

[0005] An aim of the present invention is to remedy this problem of poor distribution of the liquid and gaseous phases of a heat transfer fluid and to do so with a view to increasing the efficiency of heat transfer. Statement of the invention

[0006] The present invention thus relates to a heat exchange device configured to allow the exchange between a first and a second heat transfer fluid, said device comprising a bundle of plates stacked on top of each other to form between each plate a channel in which one or other of the heat transfer fluids circulates, each plate of the bundle comprising a distribution zone comprising means for distributing the first or second heat transfer fluids, a collection zone comprising means for recovering the first or second heat transfer fluids and a flow zone between the distribution zone and the collection zone, characterized in that the channels of the first fluid comprise at the junction between the distribution zone and the flow zone fluid restriction means configured to homogenize a liquid phase and a gaseous phase of the first fluid when the first fluid enters the flow zone.

[0007] Thanks to the invention, the first heat transfer fluid is homogenized upon entering the channel by a better distribution of the liquid and gaseous phases, which makes it possible to increase the heat transfer of the heat exchange device.

[0008] It is thus understood that the fluid restriction means are placed outside the distribution zone, at the interface with the flow zone.

[0009] According to one aspect of the invention, the fluid restriction means comprise a reduction in the cross-section of the passage of the first fluid in a direction perpendicular to the stacking axis of the plates of the bundle.

[0010] According to one aspect of the invention, the fluid restriction means comprise a portion of constant passage section in the direction of flow of the fluid. In other words, this portion has a passage section size which is constant. It is therefore understood that the passage section, in the direction of flow of the fluid, on this portion, does not change in dimension.

[0011] According to one aspect of the invention and alternatively, the fluid restriction means comprise a portion of passage section varying progressively. Preferably, this portion has a decreasing passage section size, with a larger section on the distribution zone side than on the flow zone side.

[0012] According to one aspect of the invention, the fluid restriction means comprise the portion of constant passage section and the portion of progressively varying passage section.

[0013] According to one aspect of the invention, the fluid restriction means extend over the entire height of the channel.

[0014] According to one aspect of the invention, the fluid restriction means are made from the same material as the means for distributing the first fluid.

[0015] According to one aspect of the invention, the fluid restriction means are made from the same material as the plates forming the channels of the first fluid.

[0016] According to one aspect of the invention and alternatively, the fluid restriction means are elements added to the plates forming the channels of the first fluid.

[0017] According to one aspect of the invention, the channels of the first fluid comprise at the junction between the fluid restriction means and the flow zone of the expansion means of the first fluid. The expansion means are a depression zone making it possible to increase the homogeneity of the liquid and gas phases of the first fluid when the fluid enters the flow zone.

[0018] According to one aspect of the invention, the expansion means comprise an enlargement of the passage section of the first fluid in a direction perpendicular to the stacking axis of the plates of the bundle.

[0019] According to one aspect of the invention, the expansion means have an inverse symmetry to the fluid restriction means. It is thus understood that when the fluid restriction means comprise a progressive reduction in section, the widening of the section of the fluid passage follows the same evolution as the restriction of the section of the fluid passage.

[0020] According to one aspect of the invention, the means for distributing the first fluid comprise at least one collector, the fluid restriction means comprise a single reduction in the cross-section of the passage of the first fluid per collector. It is thus understood that the width of the cross-section of the passage of the fluid at the level of the fluid restriction is smaller than the width of the at least one collector.

[0021] According to one aspect of the invention, the means for distributing the first fluid comprise several collectors.

[0022] According to one aspect of the invention, for each plate, the plurality of distribution manifolds of the first fluid is arranged along one end of the plate. The end is preferably a plate edge perpendicular to the main direction of flow of the first fluid in the channel.

[0023] According to one aspect of the invention, the circulation of the first fluid in the channels comprises a single pass.

[0024] According to one aspect of the invention, the means for distributing the second fluid comprise an inlet manifold and the means for recovering the second fluid comprise an outlet manifold.

[0025] According to one aspect of the invention, the inlet and outlet manifolds of the second fluid are each arranged at one end of the channels of the second fluid.

[0026] According to one aspect of the invention, the circulation of the second fluid in the channels comprises a single pass.

[0027] According to one aspect of the invention, the means for distributing the first fluid and the means for distributing the second fluid are placed at different ends of the plates. It is thus understood that the two heat transfer fluids circulate between the plates in a crossed manner.

[0028] According to one aspect of the invention and alternatively, the means for distributing the first fluid and the means for distributing the second fluid are placed at the same end of the plates. We thus understand that the two heat transfer fluids circulate between the plates in parallel.

[0029] According to one aspect of the invention, the heat exchange device comprises a distribution chamber for the first fluid placed on an end plate of the stack of plates.

[0030] According to one aspect of the invention, the means for recovering the first fluid are free from fluid restrictions.

[0031] According to one aspect of the invention, the means for recovering the first fluid comprise a plurality of collection collectors.

[0032] According to one aspect of the invention, the collectors for collecting the first fluid are arranged in the bundle along an edge of the plates opposite the edge comprising the plurality of distribution collectors.

[0033] According to one aspect of the invention, the heat exchange device comprises an internal element arranged in the flow zone of the first fluid and / or the second heat transfer fluid, said internal element is configured to disturb the flow of the fluid in order to increase the heat exchange coefficient between the two heat transfer fluids.

[0034] According to one aspect of the invention, the internal element comprises reliefs of alternating crenellations, called in English “offsets”.

[0035] According to one aspect of the invention, the internal element comprises louvered openings.

[0036] According to one aspect of the invention, the internal element occupies at least part of the flow zone and is spaced from the fluid restriction means by a distribution space.

[0037] According to one aspect of the invention, the channels comprising the internal element comprise at least one stop arranged on either side of the internal element and configured to hold the internal elements in position in a direction of flow of the first or second heat transfer fluids in each channel provided with an internal element and to guarantee the distribution space in these channels.

[0038] According to one aspect of the invention and as an alternative to the internal element, the flow zone of the first fluid and / or the second heat transfer fluid comprises a plurality of protrusions configured to disturb the flow of the fluid in order to increase the heat exchange coefficient between the two heat transfer fluids.

[0039] According to one aspect of the invention and as an alternative to the internal element, the flow zone may be formed from a corrugated plate bottom, the corrugations being configured to disturb the flow of the fluid in order to increase the heat exchange coefficient between the two heat transfer fluids.

[0040] According to one aspect of the invention, the inlet and outlet manifolds of the second fluid comprise sealing walls disposed in the channels of the first fluid and configured to prevent the second fluid from flowing into the channels dedicated to the first fluid.

[0041] According to one aspect of the invention, the sealing walls of the second fluid comprise the stops.

[0042] According to one aspect of the invention, the bundle of plates is welded or brazed.

[0043] According to one aspect of the invention, the means for distributing and collecting the first fluid comprises sealing walls disposed in the second fluid channels and configured to prevent the first fluid from flowing into the second fluid channels.

[0044] According to one aspect of the invention, the sealing walls of the first fluid comprise the stops.

[0045] According to one aspect of the invention and according to a first embodiment, the plates of the bundle are formed by cutting. According to the first embodiment in which the fluid restriction means are made from the same material as the means for distributing the first fluid, said fluid restriction and distribution means are obtained directly by cutting the plates. The cutting means are all those known to those skilled in the art.

[0046] According to one aspect of the invention, the height of the channels of the first fluid is defined by the thickness of the plates forming the channels of the first fluid.

[0047] According to one aspect of the invention, the height of the channels of the second fluid is defined by the thickness of the plates forming the channels of the second fluid.

[0048] According to one aspect of the invention, the heat exchange device comprises flat plates configured to form an upper wall and a lower wall for each channel of the first and second heat transfer fluids.

[0049] According to one aspect of the invention and according to a second embodiment, the plates of the beam are formed by stamping.

[0050] According to one aspect of the invention, all the plates of the bundle apart from the end plates of the bundle are identical and comprise a standard plate and the fluid restriction means formed by added elements as described above.

[0051] According to one aspect of the invention, the sealing walls of the inlet and outlet manifolds are also elements added to the standard plates and may be made in one piece with the added elements forming the fluid restriction means.

[0052] According to one aspect of the invention, the added elements forming the fluid restriction means of the channels of the first fluid define the height of the channels of the first fluid. Brief description of the drawings

[0053] Other characteristics, details and advantages of the invention will emerge more clearly on reading the description given below for information purposes in relation to drawings in which: - [Fig.l] is an overall schematic view of a heat exchange device according to the invention; - [Fig.2] is a schematic view of a channel of the first heat transfer fluid of the heat exchange device of [Fig.l] according to a first embodiment of the invention; - [Fig.3] is an enlarged schematic view of the fluidic restriction means of the first heat transfer fluid in the first fluid channel of the heat exchange device of [Fig.2] according to a first embodiment of the invention; - [Fig.4] is a schematic view of a channel of the second heat transfer fluid of the heat exchange device of [Fig.l] according to a first embodiment of the invention; - [Fig.5] is a schematic sectional and enlarged view of the means for distributing the first heat transfer fluid of the heat exchange device of [Fig.l] according to a first embodiment of the invention; - [Fig.6] is a schematic view of a standard plate of the heat exchange device according to a second embodiment of the invention; - [Fig.7] is a schematic view of a standard plate of [Fig.6] including the elements reported for the first heat transfer fluid; - [Fig.8] is a schematic view of a standard plate of [Fig.6] including the elements added for the second heat transfer fluid; - [Fig.9] is a schematic view of different possible profiles of the means of fluid restrictions according to the invention.

[0054] It should first be noted that although the figures set out the invention in detail for its implementation, these figures can of course be used to better define the invention where appropriate. It should also be noted that these figures only set out a few examples of embodiments of the invention. Detailed description

[0055] [Fig.l] illustrates a heat exchange device 100 according to the invention configured to allow the exchange between a first and a second heat transfer fluid, said device 100 comprising a bundle 200 of plates stacked on top of each other to form between each plate a channel 1, 2 in which one or other of the heat transfer fluids circulates, each plate of the bundle 200 comprising a zone of dis 3 comprising distribution means 31 for the first or second heat transfer fluids, a collection zone 4 comprising recovery means 41 for the first or second heat transfer fluids and a flow zone 5 between the distribution zone 3 and the collection zone 4. As illustrated in FIGS. 2, 3, 5 and 7, the invention is characterized in that the channels 1 of the first fluid comprise at the junction between the distribution zone 3 and the flow zone fluid restriction means 6 configured to homogenize a liquid phase and a gaseous phase of the first fluid when the first fluid enters the flow zone 5.

[0056] It is thus understood that the fluid restriction means 6 are placed outside the distribution zone 3, at the interface with the flow zone 5.

[0057] The fluid restriction means 6 comprise a reduction in the cross-section of the passage of the first fluid in a direction perpendicular to the stacking axis of the plates of the bundle 200.

[0058] [Fig. 9] illustrates the different possible profiles of the fluid restriction means 6. In Figures 9A and 9D, the fluid restriction means 6 comprise a portion of constant passage section in the direction of flow of the fluid. In Figures 9B, 9C and 9D, the fluid restriction means 6 comprise a portion of progressively varying section reduction. Preferably, this portion has a decreasing passage section size, with a larger section on the side of the distribution zone 3 than on the side of the flow zone 5.

[0059] Figure 9A illustrates a profile of fluid restriction means 6 comprising only a portion of constant passage section. Figures 9B and 9C illustrate profiles of fluid restriction means 6 comprising only a portion of progressively varying passage section. Figure 9D illustrates a profile of fluid restriction means 6 comprising a portion of progressively varying fluid passage section followed by a portion of constant passage section in the direction of flow of the fluid.

[0060] The fluid restriction means 6 extend over the entire height of the channel.

[0061] The fluid restriction means 6 are made from the same material as the means of dis tribution 31 of the first fluid.

[0062] The fluid restriction means 6 are made from the same material as the plates forming the channels 1 of the first fluid as illustrated in FIGS. 2 to 5 or may be elements added to the plates forming the channels 1 of the first fluid as illustrated in FIGS. 6 to 8.

[0063] Figures 2, 3, 5, 7, 9B and 9C show that the channels 1 of the first fluid can comprise at the junction between the fluid restriction means 6 and the flow zone 5 means 7 for expanding the first fluid.

[0064] The expansion means 7 comprise a widening of the section of the passage of the first fluid in a direction perpendicular to the stacking axis of the plates of the bundle 200.

[0065] The expansion means 7 have an inverse symmetry to the fluid restriction means 6. It is thus understood that when the fluid restriction means 6 comprise a progressive reduction in section, the widening of the section of the fluid passage follows the same evolution as the restriction of the section of the fluid passage.

[0066] The distribution means 31 of the first fluid comprise at least one collector 310, the fluid restriction means 6 comprise a single reduction in the section of the passage of the first fluid per collector 310.

[0067] As particularly illustrated in Figures 2 to 8, the distribution means 31 of the first fluid may comprise several collectors 310.

[0068] For each plate, the plurality of collectors 310 for distributing the first fluid is arranged along one end of the plate. The end is preferably a plate edge perpendicular to the main direction of flow of the first fluid in the channel 1.

[0069] The circulation of the first fluid in the channels 1 comprises a single pass.

[0070] The means 31 for distributing the second fluid comprise an inlet manifold 320 and the means 41 for recovering the second fluid comprise an outlet collector 420.

[0071] The inlet manifolds 320 and outlet manifolds 420 of the second fluid are each arranged at one end of the channels 2 of the second fluid.

[0072] The circulation of the second fluid in the channels 2 comprises a single pass.

[0073] The distribution means 31 of the first fluid and the distribution means 31 of the second fluid are placed at the same end of the plates. It is thus understood that the two heat transfer fluids circulate between the plates in parallel.

[0074] Alternatively and not illustrated, the distribution means 31 of the first fluid and the distribution means 31 of the second fluid are placed at different ends of the plates. It is thus understood that the two heat transfer fluids circulate between the plates in a crossed manner.

[0075] The heat exchange device 100 comprises a distribution chamber 330 for the first fluid, visible in FIGS. 1 and 5, and placed on an end plate 8 of the stack of plates.

[0076] In the examples illustrated, the means 41 for recovering the first fluid are devoid of fluid restriction means 6.

[0077] The means 41 for recovering the first fluid comprise a plurality of collection collectors 410.

[0078] The collection collectors 410 of the first fluid are arranged in the bundle 200 along an edge of the plates opposite the edge comprising the plurality of distribution collectors 310.

[0079] As shown in the figures, the heat exchange device 100 may comprise an internal element 9 arranged in the flow zone 5 of the first fluid and / or the second heat transfer fluid, said internal element 9 is configured to disturb the flow of the fluid in order to increase the heat exchange coefficient between the two heat transfer fluids.

[0080] The internal element 9 comprises reliefs of alternating crenellations, called in English “offsets”. Alternatively, the internal element 9 may comprise openings in the form of shutters.

[0081] The internal element 9 occupies at least part of the flow zone 5 and is spaced from the fluid restriction means 6 by a distribution space 10.

[0082] The channels 1, 2 comprising the internal element 9 comprise at least one stop 11 arranged on either side of the internal element 9 and configured to hold the internal elements in position in a direction of flow of the first or second heat transfer fluids in each channel 1, 2 provided with an internal element 9 and to guarantee the distribution space 10 in these channels 1, 2.

[0083] Alternatively and not illustrated in the internal element, the flow zone of the first fluid and / or the second heat transfer fluid comprises a plurality of protrusions configured to disturb the flow of the fluid in order to increase the heat exchange coefficient between the two heat transfer fluids. These protrusions can be distributed locally over the flow zone or extend in length along a direction of flow of the fluids.

[0084] Alternatively to the internal element and not illustrated in the figures, the flow zone can be formed from a corrugated plate bottom, the corrugations being configured to disturb the flow of the fluid in order to increase the heat exchange coefficient between the two heat transfer fluids.

[0085] The inlet manifolds 320 and outlet manifolds 420 of the second fluid comprise sealing walls 12 arranged in the channels 1 of the first fluid and configured to prevent the second fluid from circulating in the channels 1 dedicated to the first fluid.

[0086] The sealing walls 12 of the second fluid comprise the stops 11.

[0087] The bundle 200 of plates is welded or brazed.

[0088] The means for distributing 31 and collecting 41 the first fluid comprise sealing walls 15 arranged in the channels 2 of the second fluid and configured to prevent the first fluid from circulating in the channels 2 of the second fluid.

[0089] The sealing walls 15 of the first fluid comprise the stops 11.

[0090] According to a first embodiment of the invention illustrated in Figures 2 to 5, the plates of the bundle 200 are formed by cutting. According to the first embodiment in which the fluid restriction means 6 are made from the same material as the distribution means 31 of the first fluid, said fluid restriction means 6 and distribution means 31 are obtained directly by cutting the plates. The cutting means are all those known to those skilled in the art.

[0091] The height of the channels 1 of the first fluid is defined by the thickness of the plates forming the channels 1 of the first fluid.

[0092] The height of the channels 2 of the second fluid is defined by the thickness of the plates forming the channels 2 of the second fluid.

[0093] The heat exchange device 100 comprises flat plates 13 configured to form an upper wall 131 and a lower wall 132 for each channel 1, 2 of the first and second heat transfer fluids.

[0094] According to a second embodiment of the invention illustrated in Figures 6 to 8, the plates of the beam 200 are formed by stamping.

[0095] All the plates of the bundle 200 apart from the end plates 8 of the bundle 200 are identical and comprise a standard plate 14, particularly visible in [Fig.6], and the fluid restriction means 6 formed by added elements as described previously.

[0096] In this embodiment, the sealing walls 12 of the inlet 320 and outlet 420 manifolds are also elements added to the standard plates 14 and may be made in one piece with the added elements forming the fluid restriction means 6.

[0097] The added elements forming the fluid restriction means 6 of the channels 1 of the first fluid define the height of the channels 1 of the first fluid.

Claims

Claims

1. Heat exchange device (100) configured to allow the exchange between a first and a second heat transfer fluid, said device (100) comprising a bundle (200) of plates stacked on top of each other to form between each plate a channel (1, 2) in which one or other of the heat transfer fluids circulates, each plate of the bundle (200) comprising a distribution zone (3) comprising means for distributing (31) the first or second heat transfer fluids, a collection zone (4) comprising means for recovering (41) the first or second heat transfer fluids and a flow zone (5) between the distribution zone (3) and the collection zone (4),characterized in that the channels (1) of the first fluid comprise at the junction between the distribution zone (3) and the flow zone fluid restriction means (6) configured to homogenize a liquid phase and a gaseous phase of the first fluid when the first fluid enters the flow zone (5).,

2. Heat exchange device (100) according to the preceding claim, in which the fluid restriction means (6) comprise a reduction in the section of the passage of the first fluid in a direction perpendicular to the stacking axis of the plates of the bundle (200).

3. Heat exchange device (100) according to one of the preceding claims, in which the fluid restriction means (6) comprise a portion of constant passage section in the direction of flow of the fluid.

4. Heat exchange device (100) according to one of the preceding claims, in which the fluid restriction means (6) comprise a portion of passage section varying progressively in the direction of flow of the fluid.

5. Heat exchange device (100) according to one of the preceding claims, in which the fluid restriction means (6) extend over the entire height of the channel.

6. Heat exchange device (100) according to one of the preceding claims, in which the fluid restriction means (6) are made from the same material as the distribution means (31) of the first fluid.

7. Heat exchange device (100) according to the preceding claim, in which the fluid restriction means (6) are made from the same material as the plates forming the channels (1) of the first fluid.

8. Heat exchange device (100) according to claim 6, in which the fluid restriction means (6) are elements attached to the plates forming the channels (1) of the first fluid.

9. Heat exchange device (100) according to one of the preceding claims, in which the channels (1) of the first fluid comprise at the junction between the fluid restriction means (6) and the flow zone (5) means (7) for expanding the first fluid.

10. Heat exchange device (100) according to the preceding claim, in which the expansion means (7) comprise an enlargement of the passage section of the first fluid in a direction perpendicular to the stacking axis of the plates of the bundle (200).

Images