LU101389B1

LU101389B1 - Heat exchanger for a vehicle

Info

Publication number: LU101389B1
Application number: LU101389A
Authority: LU
Inventors: Sebastian Challand; Rémi Grunewald; Hervé Damotte; Adam PLATEK
Original assignee: Ht Holding Luxembourg S A
Priority date: 2019-09-12
Filing date: 2019-09-12
Publication date: 2021-03-19

Abstract

The invention relates to a heat exchanger (1) for a vehicle. In order to optimise a heat exchanger for cooling a plurality of devices in a vehicle, the invention provides that the heat exchanger comprises: - an inlet tank (10) for a liquid coolant, extending over a tank length along a first axis (A); - an outlet tank (30) with at least one outlet port (31, 32) for connection to an outlet pipe (42, 43); - an exchanger core (20) disposed for heat exchange of the liquid coolant with ambient air and comprising a plurality of exchanger tubes (21) connecting a discharge volume (10.1) of the inlet tank (10) to the outlet tank (30); and - an intake volume (10.2) that is at least partially disposed inside the inlet tank (10) and that is connected to a plurality of inlet ports (15, 16, 17), each of which is adapted for connection to an inlet pipe (40, 41), wherein a partitioning wall (12) extending inside the inlet tank (10) along the first axis (A) is interposed between the discharge volume (10.1) and the intake volume (10.2) and at least one transfer passage (13) is adapted for fluid communication between the discharge volume (10.1) and the intake volume (10.2).

Description

HEAT EXCHANGER FOR A VEHICLE Technical Field

[0001] The invention relates to a heat exchanger for a vehicle. Background Art

[0002] In vehicles such as passenger cars or trucks, heat exchangers are used as part of cooling circuits, which in turn are needed for cooling vehicle components like the engine, the transmission etc. These cooling circuits typically employ a liquid coolant, which receives heat from the vehicle components and transfers heat to ambient air at the main heat exchanger, like a radiator installed in the front of the vehicle. The necessary airflow can be provided by forced or natural convection to the core of the radiator. Commonly, a cooling circuit has two or more branches downstream of a pump, in which individual devices are integrated, and the branches are connected to the main heat exchanger. Due to the different heat transfer in these devices, the coolant flows arriving at the heat exchanger have different temperatures and mass flows. According to prior art, the different coolant flows with different temperatures are merged and mixed together before entering in the heat exchanger. This radiator has then only one inlet connector (or possibly several connectors) which is entered by the coolant with the same temperature of the coolant flow.

[0003] However, merging the different coolant flows leads to several problems. This is partially due to the fact that the different devices to be cooled can be positioned at different locations in the car. Therefore, a considerable amount of piping is necessary to join these coolant flows. This piping can be complex, space consuming, material consuming and energy consuming. It often leads to added flow friction by bows which are necessary to route the different pipes. Also, diameter adaptations are often necessary and multiple mixing areas are created, each of which needs a connector, e.g. a Y-connector.

[0004] On the other hand, introducing several coolant flows with different temperatures into the heat exchanger, especially the exchanger core, would lead to increased thermal stress, thus reducing the life time of the heat exchanger. Technical Problem

[0005] It is thus an object of the present invention to optimise a heat exchanger for cooling a plurality of devices in a vehicle.

[0006] This problem is solved by a heat exchanger according to claim 1. General Description of the Invention

[0007] The invention provides a heat exchanger for a vehicle. The vehicle may be, e.g., a passenger car or a truck, but an application to other vehicles is also possible. The heat exchanger is a liquid-to-air heat exchanger and is normally a radiator which can be used as main or secondary radiator, to be mounted in a front section of the vehicle or in any part of the vehicle, depending on the application.

[0008] The heat exchanger comprises an inlet tank for a liquid coolant, extending over a tank length along a first axis. The inlet tank, which at least in some embodiments may be referred to as an inlet manifold, is adapted for containing a liquid coolant during operation. The inlet tank can receive liquid coolant, e.g., from vehicle components like a water jacket of an engine, a transmission cooler, a battery set, or the like, which liquid coolant is then cooled in the heat exchanger before being returned to the vehicle cooling circuit. The inlet tank extends over a tank length along a first axis. Normally, it is elongate with respect to the first axis so that the tank length is the largest dimension of the inlet tank.

[0009] The heat exchanger further comprises an outlet tank with at least one outlet port for connection to an outlet pipe. The outlet tank, which at least in some embodiments may be referred to as outlet manifold, may have the same or similar dimensions as the inlet tank. In particular, it may also have a length equal to the tank length along the first axis. It may also be elongate with respect to the first axis. It is understood that the outlet tank is also adapted to contain liquid coolant. During operation, the liquid coolant is redistributed from the outlet tank to the vehicle components via the at least one outlet port and at least one outlet pipe. Every outlet port is adapted for connection to a coolant outlet pipe, so that in assembled state, the number of coolant outlet pipes corresponds to the number of outlet ports.

[0010] Further, the heat exchanger comprises an exchanger core disposed for heat exchange of the liquid coolant with ambient air and comprising a plurality of exchanger tubes connecting a discharge volume of the inlet tank to the outlet tank. The exchanger core may extend along the first axis and along a second axis perpendicular to the first axis. The exchanger tubes are hollow and may have any appropriate cross- sectional shape, e.g. rectangular, round or oval. During operation, ambient air flows along the exchanger core, whereby a heat exchange between the ambient air and liquid coolant is promoted. In other words, the heat exchange process is almost entirely performed at the exchanger core. The liquid coolant flows through exchanger tubes of the exchanger core. Every exchanger tube is connected between a discharge volume of the inlet tank and the outlet tank, i.e. it can receive liquid coolant from the discharge volume and transfer the liquid coolant towards the outlet tank. In general, the number and the size of the exchanger tubes is not limited by the invention. Also, at least the flow of one exchanger row could be S-shaped or have a meandering shape. It could comprise at least one portion that is directed parallel to the first axis. The invention is not limited to these possibilities, though. Commonly the exchanger tubes may have a cross-section of a few mm? or even less than 1 mm? It is understood that the exchanger core normally comprises structures as extended surface like fins in order to increase the surface of the exchanger core and thus enhance the heat exchange with the ambient air. The fins may be located between the tubes and may partially or totally cover the tube width. The extended surface is commonly named “secondary surface” in opposition to the tube surface named “primary surface’.

[0011] According to a common embodiment, commonly referred to as “I-flow”, a plurality of exchanger tubes extend along the second axis, with the inlet tank disposed on one side of the exchanger pipes and the outlet tank disposed on an opposite side thereof. However, the inlet tank and the outlet tank could be disposed next to each other (along first direction) and the exchanger tubes could be disposed in a U-shape, leading away from the inlet tank along the second axis and then back along the second axis to the outlet tank. Still alternatively, the inlet tank and the outlet tank could be disposed next to each other (along first direction) and a first set of exchanger tubes would communicate with an intermediate collecting tank opposite the inlet tank. Coolant arriving at the intermediate tank would flow back though a second set of exchanger tubes extending from the intermediate tank to the outlet tank. Both latter configurations are known as U-flow. These kinds of configurations are generally known in the art.

[0012] According to the invention, the heat exchanger further comprises an intake volume that is at least partially disposed inside the inlet tank and that is connected to a plurality of inlet ports (i.e. at least two), each of which is adapted for connection to a coolant inlet pipe, wherein a partitioning wall extending inside the inlet tank along the first axis is interposed between the discharge volume and the intake volume and at least one transfer passage is adapted for fluid communication between the discharge volume and the intake volume. The intake volume is at least partially disposed inside the inlet tank; that is in embodiments the intake volume is disposed entirely inside the tank and in other embodiments the intake volume may extend out of the inlet tank. The intake volume is connected to, i.e. in fluid communication with, a plurality of inlet ports. Each inlet port is adapted for connection to a coolant inlet pipe, i.e. in operational state, a coolant inlet pipe is connected to each inlet port. The coolant inlet pipes are adapted to transfer liquid coolant from vehicle devices as mentioned above to the heat exchanger. The number of outlet ports (and thus the number of outlet pipes) can be identical to the number of inlet ports (and thus the number of inlet pipes), but the invention is not limited to this. A partitioning wall extends inside the inlet tank along the first axis. It is usually parallel to the first axis, but could also at least partially be disposed at an angle with respect to the first axis. Generally, the partitioning wall can be straight, curved and/or angled. The partitioning wall is interposed between the discharge volume and the intake volume. One could also say that inside the inlet tank, the discharge volume and the intake volume are separated by the partitioning wall. However, the first and intake volume are not completely separated, but at least one transfer passage is adapted for fluid communication between the two volumes. Le. liquid coolant can be transferred from the intake volume to the discharge volume (and, in principle, vice versa) through each transfer passage.

[0013] The idea of the invention is to employ an intake volume and a discharge volume that are separated by the partitioning wall instead of a single inner volume of an inlet tank according to prior art. The discharge volume is (directly) connected to the exchanger pipes of the exchanger core, while the intake volume is (directly) connected to the inlet pipes via the inlet ports. Since the partitioning wall is interposed between the intake and discharge volumes, direct flow between the inlet ports and the exchanger tubes can be essentially avoided. The liquid coolant entering the inlet tank in the intake volume ; has to go through the transfer passage(s) to get from an inlet port to an exchanger pipe. Each transfer passage can be regarded as a flow regulator for the coolant flow. Therefore, in general, coolant from different inlet pipes flows through the same transfer passage. Thus, coolant streams with (initially) different temperatures are forced into contact inside and/or before the transfer passage, which results in a mixing effect. When the coolant reaches the discharge volume, it is intermixed at least to some extent, wherefore temperature differences between the coolant streams from different inlet pipes are reduced or even eliminated. This leads to a highly uniform temperature distribution within the exchanger core, thereby avoiding unnecessary thermal stress to the exchanger core. On the other hand, since the mixing occurs within the inlet tank, there is no need for external mixing, wherefore any external piping, like the inlet pipes connected to the heat exchanger, can be kept simple. The need for bended portions, which would result in considerable pressure loss, is greatly reduced. There is no need for complicated merging connections outside the heat exchanger. Rather, there could be one inlet pipe for each vehicle device that needs to be cooled, with every inlet pipe being connected to an inlet port. Then the different coolant streams are at least partially mixed as they traverse the at least one transfer passage (and already as the flows come into contact with each other upstream of the transfer passage).

[0014] It should be noted that although the function of the partitioning wall is to prevent unhindered, direct coolant flow between the inlet ports and the exchanger pipes, it does not have to be completely fluid tight. Especially minor leakage through or around the partitioning wall will not significantly impair the mixing effect or lead to thermal stress in the core. This facilitates the construction of the heat exchanger, since the requirements on the robustness of the partitioning wall and its fluid-tightness are less strict.

[0015] According to a common design of heat exchangers in vehicles, the first axis is a substantially vertical axis, i.e. it is either vertical or at an angle of less than 20° or less than 10° with respect to the vertical direction. In other words, the inlet tank (and usually also the outlet tank) is elongate along the vertical axis, which of course refers to the position of the heat exchanger when installed in the vehicle. In this case, the above- mentioned second axis in this case is a horizontal axis. This design corresponds to a cross-flow radiator. According to another design, the first axis is a horizontal axis (or is at an angle of less than 20° or less than 10° with respect to the horizontal direction). In this embodiment, the inlet tank (and usually the outlet tank) is elongate along the horizontal axis. The second axis would then be a vertical axis. This design corresponds to a down- flow radiator.

[0016] There are various possibilities for the positions of the inlet ports. According to one preferred embodiment, at least one inlet port is disposed at an end region of the intake volume with respect to the first axis and is directed axially with respect to the first axis, i.e. parallel to the first axis. If the first axis is a vertical axis, the respective inlet port is disposed at an upper end region or a lower end region of the intake volume. In particular, it may be disposed at the upper end region. The inlet port is directed axially with respect to the first axis, which means that it is adapted for a coolant flow along the first axis. Also, it is adapted so that an inlet pipe connected to this inlet port runs along the first axis, at least in the vicinity of the inlet port. This arrangement may be beneficial for several reasons, in particular, if the inlet port is disposed at the upper end, this facilitates degassing of the intake volume and of the heat exchanger in general.

[0017] Alternatively or additionally, at least one inlet port can be directed radially with respect to the first axis, i.e. transversally to the first axis. If the first axis is vertical, the respective inlet port is directed horizontally. A corresponding coolant inlet pipe will also be directed horizontally. The respective inlet pipe could be disposed at the same level as the vehicle device that is to be cooled so that the inlet pipe be disposed along a horizontal plane. in particular, the heat exchanger could comprise one inlet port disposed in the upper end region and directed vertically and at least one inlet port (possibly several inlet ports) that is (are) directed horizontally. The orientation of the inlet port with respect to the first axis, i.e. its angular position about the first axis, may be chosen in various ways. E.g. if the exchanger core extends along the first axis and the second axis, the inlet port could be directed parallel to the second axis, perpendicular to the second axis or at any other angle with respect to the second axis (although some angular positions of course may be impossible due to the available building space).

[0018] Commonly, at least two inlet ports are offset along the first axis. With the first axis being the vertical axis, these at least two inlet ports are vertically offset, i.e. they are disposed at different vertical positions. It is conceivable that one inlet port is disposed in a similar vertical position as a transfer passage so that coolant can flow more or less directly from this inlet port to the exchanger pipe(s), while at least one inlet port is disposed at a different vertical position, where a direct flow path to the exchanger pipe(s) is blocked by the partitioning wall, which extends vertically within the inlet tank.

[0019] According to one embodiment, the intake volume extends along the first axis beyond the walls of the inlet tank and at least one inlet port is offset from the inlet tank along the first axis. If the first axis is a vertical axis, the intake volume may extend vertically above (or below) the inlet tank and at least one inlet port may be disposed above (or below) with respect to the vertical axis. This configuration may be advantageous if one vehicle device to be cooled is disposed above or below the inlet tank with respect to the vertical axis. By providing an inlet port above or below the inlet tank, the respective inlet pipe can be disposed (more or less) in a single horizontal plane, avoiding unnecessary bends to adjust the level for connection to the intake volume.

[0020] Although there are various possibilities how the at least one transfer passage could be realized, e.g. by a pipe connecting the discharge volume and the intake volume, it is preferred that at least one transfer passage is a transfer opening in the partitioning wall. This opening or aperture, which can also be referred to as a through-hole or cutout, can be realized at low costs. This embodiment also helps to minimize the total weight of the heat exchanger. Preferably, every transfer passage is a transfer opening in the partitioning wall. The shape of the respective transfer opening could e.g. be circular, oval, polygonal, rectangular or another shape.

[0021] According to one embodiment, the heat exchanger comprises a plurality of transfer passages. This can be beneficial for several reasons. For instance, if every transfer passage is a transfer opening in the partitioning wall, the mechanical stability of the partitioning wall could be negatively affected by a single, large opening as opposed to a plurality of smaller openings. Also, a plurality of smaller openings could increase the local turbulence within the coolant stream, thereby enhancing the intended mixing effect. It should be noted, though, that mixing normally occurs by the contact of different coolant streams which occurs mostly before they enter the transfer passage(s). Thus, creation of local turbulence by the openings usually is of minor importance. Finally, a plurality of openings could help to direct the coolant flow in a desired way.

[0022] It is preferred that every transfer passage is disposed in a transfer region of the inlet tank, which transfer region extends over less than 30% of the tank length. More specifically, the transfer region could extend over less than 20% or even less than 10% of the tank length. This configuration increases the above-mentioned flow regulator effect so that the coolant flow from each inlet port is forced a comparatively small transfer region, where it mixes, already upstream of the transfer passage(s), with the other coolant flow(s). It is also preferred that the transfer region extends over less 30% of the length of the partitioning wall, preferably less than 20% or less than 10%.

[0023] Even if the location and extent of the at least one transfer passage is restricted to the transfer region, the location of the transfer region as such could be chosen in various ways. For example, if the first axis is a vertical axis, the transfer region could be disposed in a lower end region or in the middle of the inlet tank. It is preferred, though, that the transfer region is disposed in an upper end region of the inlet tank. In particular it may be disposed at an upper end of the inlet tank. This configuration is beneficial when considering degassing of the liquid coolant in the intake volume and/or the discharge volume.

[0024] According to one embodiment, all transfer passages are disposed at the same level along the first axis. If the first axis is a vertical axis, this means that all transfer passages are disposed at the same vertical level (i.e. the same height). In general, this embodiment coincides with a configuration where every transfer passage is disposed in a transfer region extending over less than 30% of the tank length.

[0025] While the geometry of the inlet tank is not limited within the scope of the invention, the inlet tank may in particular have an outer wall extending along the first axis. The outer wall (or at least a portion of the outer wall) may be symmetric with respect to the first axis or it may be symmetric with respect to a plane that is parallel to the first axis. The outer wall may in particular be a cylindrical wall. Here and in the following, the term “cylindrical” not only includes a circular cross-section (along a plane perpendicular to the first axis) but also any other shape, like oval, polygonal, rectangular, D-shaped etc. Apart from a cylindrical shape where the cross-section is constant along the first axis, the cross- section may also vary along the first axis. At either end with respect to the first axis, an end wall may be connected to the outer wall. For instance, if the outer wall has a circular cross-section, the respective end wall is normally circular.

[0026] There are various possible configurations for the partitioning wall, which may be chosen under manufacturing aspects, stability aspects of the heat exchanger and the inlet tank, as well as aspects of advantageous directing of the coolant flow. According to one embodiment, the partitioning wall is a cylindrical inner wall at least partially disposed in a spaced-apart manner on an inside of an outer wall of the inlet tank, so that inside the inlet tank, the discharge volume is surrounded by (respectively disposed circumferentially around) the intake volume. The partitioning wall is cylindrical and is disposed inside the outer wall, i.e. it is surrounded by the outer wall. As mentioned above, the outer wall could be cylindrical. The partitioning wall is spaced-apart from the outer wall, i.e. there is a spacing in between which defines the discharge volume. The volume inside the partitioning wall, on the other hand, is the intake volume. Especially in this embodiment, a plurality of transfer openings may be disposed circumferentially around the partitioning wall. This facilitates coolant flow from the intake volume into all parts of the discharge volume. This embodiment can advantageously be combined with the above- | mentioned embodiment where the discharge volume vertically extends beyond the inlet tank. This can be realized by extending the partitioning wall beyond the first tank so that a portion of the partitioning wall is disposed inside the inlet tank and another portion is disposed outside.

[0027] If the partitioning wall is cylindrical as described above, the heat exchanger may in particular comprise at least one inlet port that is directed transversally with respect to the first axis and that extends from the outer wall of said inlet tank, through the discharge volume, to the partitioning wall. In other words, the inlet port traverses the discharge volume, which is disposed around the inlet volume. It is connected to the partitioning wall so that it communicates with the intake volume inside the partitioning wall. In this context, the inlet port may also help to suspend the partitioning wall inside the inlet tank.

[0028] According to another embodiment, the partitioning wall is connected to an outer wall of the inlet tank and extends across the inlet tank, wherein the intake volume is partially defined by the outer wall. The partitioning wall could have a curved or angled shape, but normally is just a planar (i.e. flat) wall. It extends along the first axis inside the inlet tank, thereby forming a barrier that prevents coolant flow. The planar partitioning wall could be centered with respect to the inlet tank so that the discharge volume and the intake volume have the same size, but it could also be offset to the center of the inlet tank. The at least one transfer passage could be a cutout in the partitioning wall. The portioning wall could comprise a plurality of such cutouts, in which case it could also be referred to as a perforated wall. Another option would be that the length of the partitioning wall along the first axis is smaller than the tank length, so that it does not extend through the entire inlet tank. Brief Description of the Drawings

[0029] Preferred embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a first embodiment of an inventive heat exchanger, Fig. 2 is a sectional view of the heat exchanger from fig. 1; Fig. 3 is a sectional view according to the line lll - lil in fig. 2; Fig. 4 is a sectional view of a second embodiment of an inventive heat exchanger; Fig. 5 is a sectional view of a 3“ embodiment of an inventive heat exchanger; Fig. 6 is a sectional view of a 4” embodiment of an inventive heat exchanger; Fig. 7 is a sectional view according to the line Vil — VII in fig. 6; Fig. 8a is a schematic representation of a heat exchanger in a cross-flow configuration; and Fig. 8b is a schematic representation of a heat exchanger in a down-flow configuration. Description of Preferred Embodiments

[0030] Figs.1 - 3 schematically illustrate a first embodiment of an inventive heat exchanger 1, which can be used as a radiator in a vehicle like a passenger car or a truck.

The heat exchanger 1 comprises an inlet tank 10 which is connected by an exchanger core 20 to an outlet tank 30. The inlet tank 10 and the outlet tank 30 each have a roughly cylindrical shape (with a circular cross-section) and are elongate along a first axis A, which is a vertical axis, with the inlet tank 10 extending from an upper end region 10.3 to a lower end region 10.4. It should be noted that the shape of the tanks 10, 30 is cylindrical in this example, but could be different, i.e. tank can have any appropriate cross-sectional shape. Both tanks are closed at both ends by respective end walls. The exchanger core extends along the first axis A as well as along a second axis B, which in this case is a first horizontal axis. As can be seen in the sectional views of fig. 2 and fig. 3, a cylindrical partitioning wall 12 is disposed inside the inlet tank 10 in a spaced-apart manner from a cylindrical outer wall 11 of the inlet tank 10. The cylindrical partitioning wall 12 thus has a diameter inferior to that of the inlet tank, but approximately the same length. It is closed at its lower end by the bottom end wall of the inlet tank 10 and opens at its top end into an inlet port 15. By the partitioning wall 12, the inlet tank 10 is divided into a discharge volume 10.1 between the outer wall 11 and the partitioning wall 12 and an intake volume

10.2 within the partitioning wall 12. The discharge volume 10.1 is in direct communication with a plurality of exchanger tubes 21 of the exchanger core 20, which extend parallel to the horizontal second axis B. The discharge volume thus forms a kind of inlet manifold for the exchanger core 20. The exchanger tubes 21 typically have a flattened rectangular profile (hence referred to as flat tubes) and have a flow cross section of a few mm? or less.

[0031] As an alternative to the shown embodiment, the partitioning wall 12 could be significantly shorter than the outer wall 11, so that it is spaced-apart from the bottom end wall of the inlet tank 10 and is closed at its lower end by a dedicated end wall. In such an embodiment, which could have advantages e.g. concerning thermal stress, the lower end of the partitioning wall 12 could be connected by a flexible element, like a thin metal sheet, to the bottom end wall of the inlet tank 10. Such a flexible element could act as a kind of spring.

[0032] The discharge volume 10.1 communicates with the first inlet port 15 disposed at an upper end region 10.5 thereof and with a second inlet port 16 disposed near a lower end region 10.6. The first inlet port 15 is directed along the first axis A, while the second inlet port 16 extends along a direction essentially perpendicular to the first axis A. Here, the second inlet port extends along the second axis B, but it could also extend e.g. along any other direction perpendicular to the first axis A. Each of the inlet ports 15, 16 is adapted for connection to a cooling inlet pipe 40, 41 (indicated by dashed lines), which in turn is connected to a vehicle component to be cooled, like e.g. a water jacket of an engine, a battery pack, etc. At the vehicle component, heat is transferred to the liquid coolant, which then flows to the heat exchanger 1 via the inlet pipe 40, 41. The position of HU101989 the respective inlet port 15, 16 along the first axis A may correspond to the position of the respective vehicle component, i.e. the inlet pipe 40, 41 may be disposed in a horizontal plane. Thus, the need for any bows in the inlet pipe 40, 41 is reduced to a minimum, thereby also minimizing pressure loss in the inlet pipe 40, 41 and maximizing mass flow. Also, each coolant inlet pipe 40, 41 is connected to a dedicated inlet port 15, 16, thereby eliminating the need for adapter elements for joining individual inlet pipes 40, 41 (Y- connectors or the like).

[0033] While the partitioning wall 12 is interposed between the discharge volume

10.1 and the intake volume 10.2, the two volumes are not completely isolated from each other. Rather, a plurality of transfer openings 13 in the partitioning wall 12, which allow for fluid transfer, are provided in the upper end region 10.3 of the inlet tank 10. Therefore, during operation of the heat exchanger 1, liquid coolant enters the intake volume 10.2 through the individual inlet ports 15, 16 and can be transferred to the discharge volume

10.1 via the transfer openings. In the embodiment shown, all transfer openings 13 are disposed at the same level with respect to the first axis A and are localized in a transfer region 18 that corresponds to less than 10% of a tank length of the inlet tank 10 along the first axis A. Therefore, the plurality of transfer openings 13 form a flow regulator which the liquid coolant streams have to traverse in order to reach the discharge volume 10.1 and the exchanger pipes 21 connected thereto. This in turn leads to a mixing of the individual coolant streams originating from the first inlet port 15 and the second inlet port 16. For instance, if the temperatures of these coolant streams are different, the respective temperature differences will be mitigated or even eliminated by the mixing effect. Therefore, the coolant in the discharge volume 10.1 that enters the exchanger pipes 21 has a largely homogeneous temperature distribution, which helps to reduce thermal stress on the exchanger core 20.

[0034] The position of the transfer openings 13 in the upper end region 10.5 of the intake volume 10.2 and the position of the first inlet port 15 in the upper end region 10.3 of the inlet tank 10 facilitate degassing of the discharge volume 10.1 and intake volume 10.2, as well as the heat exchanger 10 in general and the pipes 40, 41 connected thereto. In this embodiment, the transfer openings 13 have a circular shape. However, other shapes could be employed, like oval, polygonal or the like.

[0035] The liquid coolant that flows through the individual exchanger tubes 21, where heat is transferred from the coolant to ambient air around the exchanger core 20, and then into the outlet tank 30. The outlet tank 30 is designed basically as a hollow cylinder and will therefore not be described in further detail. It is connected to a first outlet port 31 and a second outlet port 32 that are adapted for connection to respective outlet pipes 42, 43. The outlet ports 31, 32 are disposed at a vertical level similar or identical to that of the respective inlet ports 15, 16. This allows the outlet pipes 42, 43 as well as the inlet pipes 40, 41 to be disposed in a single horizontal plane.

[0036] Fig. 4 is a sectional view, corresponding to fig. 2, of a second embodiment of an inventive heat exchanger 1. This embodiment is largely identical to the one shown in figs. 1 - 3 and therefore will not be discussed again in detail. In this embodiment, however, the transfer region 18 with transfer openings 13 is disposed in a lower end region 10.4 of the inlet tank 10. Although the configuration of the first embodiment may be somewhat favorable with respect to degassing behavior, the general functionality including establishment of a homogeneous temperature distribution in the exchanger core 20 is also achieved in this embodiment.

[0037] Fig. 5 is a sectional view of a third embodiment of an inventive heat exchanger 1. This embodiment is again largely identical to the first embodiment and insofar will not be explained again. Here, however, the intake volume 10.2 extends along the (vertical) first axis A beyond the inlet tank 10, i.e. it extends further downwards than the inlet tank 10. In other words, the length of the partitioning wall 12 along the first axis A is greater than the tank length. Furthermore, a third inlet port 17, which is also connected to the intake volume 10.2, is disposed below the inlet tank 10. A respective inlet pipe 40, 41 can be connected to the third inlet port 17, e.g. for transferring coolant from a vehicle device that is disposed at a lower level than the inlet tank 10. It is understood that in each of the first, second and third embodiment, more inlet ports 15, 16, 17 could be added at any level with respect to the first axis A.

[0038] Figs. 6 and 7 show a fourth embodiment of an inventive heat exchanger 1. This embodiment differs from the other embodiments in that the partitioning wall 12 is not cylindrical, but is a generally flat wall that is centered with respect to the outer wall 11 of the inlet tank 10. It is parallel to the first axis A and to a third axis C, which in this case is a second horizontal axis and is perpendicular to the first axis A and the second axis B. The partitioning wall 12 is connected to the inside of the outer wall 11 and extends from the bottom of the inlet tank 10 to a level corresponding to more than 50%, preferably more than 70%, or even approximately 80% or more, of the tank length. Thus, a transfer opening 13 is formed between the discharge volume 10.1 and the intake volume 10.2. In this embodiment, the discharge volume 10.1 is disposed in one half of the inlet tank 10 closer to the exchanger core 20 and the intake volume 10.2 is disposed in another half further away from the exchanger core 20. While in the first, second and third embodiment, 1101089 the intake volume 10.2 is defined by the partitioning wall 12, it is in this embodiment defined partially by the outer wall 11 and by the partitioning wall 12.

[0039] Figs. 8a and 8b illustrate two different designs for an inventive heat exchanger 1. The heat exchanger 1 is shown in a simplified representation and various elements are omitted for sake of simplicity. In Fig. 8a, the inlet tank 10 and the outlet tank are arranged parallel to the first axis A, which is a vertical axis. The exchanger core 20 extends along the first axis A and the horizontal second axis B. À coolant flow F inside the exchanger core 20 runs horizontally along the second axis B. This configuration, which is also shown in the embodiments of Figs. 1 - 7, corresponds to a cross-flow radiator. In Fig. 8b, the inlet tank 10 and the outlet tank 30 are arranged parallel to the first axis A, which in this case is a horizontal axis. The exchanger core extends along the first axis A and the second axis B, which in this case is a vertical axis. The coolant flow F inside the exchanger core runs along the second axis B, i.e. in a vertical direction. This configuration corresponds to a down-flow radiator. It will be understood that the embodiments shown in Figs. 1-7 could be modified — normally without major changes — to be used for a down- flow radiator as illustrated in Fig.8b.

List of Reference Signs: 1 heat exchanger inlet tank

10.1 discharge volume

10.2 intake volume

10.3, 10.5 upper end region

10.4, 10.6 lower end region 11 outer wall 12 partitioning wall 13 transfer opening 15, 16 inlet port 18 transfer region exchanger core 21 exchanger pipe outlet tank 31, 32 outlet port 40, 41 inlet pipe 42, 43 outlet pipe A first axis B second axis C third axis F coolant flow

Claims

Claims LU101389

1. A heat exchanger (1) for a vehicle, comprising: — an inlet tank (10) for a liquid coolant, extending over a tank length along a first axis (A); — an outlet tank (30) with at least one outlet port (31, 32) for connection to a coolant outlet pipe (42, 43); — an exchanger core (20) disposed for heat exchange of the liquid coolant with ambient air and comprising a plurality of exchanger tubes (21) connecting a discharge volume (10.1) of the inlet tank (10) to the outlet tank (30); and — an intake volume (10.2) that is at least partially disposed inside the inlet tank (10) and that is connected to a plurality of inlet ports (15, 16, 17), each of which is adapted for connection to a coolant inlet pipe (40, 41), wherein a partitioning wall (12) extending inside the inlet tank (10) along the first axis (A) is interposed between the discharge volume (10.1) and the intake volume (10.2) and at least one transfer passage (13) is adapted for fluid communication between the discharge volume (10.1) and the intake volume (10.2).

2. The heat exchanger according to claim 1, wherein the first axis (A) is a vertical axis or a horizontal axis.

3. The heat exchanger according to any of the preceding claims, wherein at least one coolant inlet port (15, 16, 17) is disposed at an end region (10.5, 10.6) of the intake volume (10.2) with respect to the first axis (A) and is directed axially with respect to the first axis (A).

4. The heat exchanger according to any of the preceding claims, wherein at least one coolant inlet port (15, 16, 17) is directed transversally with respect to the first axis (A).

5. The heat exchanger according to any of the preceding claims, wherein at least two LU101389 coolant inlet ports (15, 16, 17) are offset along the first axis (A).

6. The heat exchanger according to any of the preceding claims, wherein the intake volume (10.2) extends along the first axis (A) beyond the inlet tank (10) and at least one coolant inlet port (15, 16, 17) is offset from the inlet tank (10) along the first axis (A).

7. The heat exchanger according to any of the preceding claims, wherein at least one transfer passage (13) is a transfer opening in the partitioning wall (12).

8. The heat exchanger according to any of the preceding claims, comprising a plurality of transfer passages (13).

9. The heat exchanger according to claim 8, wherein every transfer passage (13) is disposed in a transfer region (18) of the inlet tank (10), which transfer region (18) extends over less than 30% of the tank length.

10. The heat exchanger according to any of the preceding claims, wherein the transfer region (18) is disposed in an upper end region (10.3) of the inlet tank.

11. The heat exchanger according to any of the preceding claims, wherein all transfer passages (13) are disposed at the same level along the first axis (A).

12. The heat exchanger according to any of the preceding claims, wherein the inlet tank (10) has an outer wall (11) extending along the first axis (A).

13. The heat exchanger according to any of the preceding claims, wherein the partitioning wall (12) is a cylindrical inner wall at least partially disposed in a spaced-apart manner on an inside of an outer wall (11) of the inlet tank (10), so that inside the inlet tank (10), the LU101389 discharge volume (10.1) surrounds the intake volume (10.2).

14. The heat exchanger according to claim 13, comprising at least one inlet port (16) that is directed transversally with respect to the first axis (A) and that extends from the outer wall (11) of said inlet tank (10), through the discharge volume (10.1), to the partitioning wall (12).

15. The heat exchanger according to any of the preceding claims, wherein the partitioning wall (12) is connected to the outer wall (11) of the inlet tank (10) and extends across the inlet tank (10), wherein the intake volume (10.2) is partially defined by the outer wall (11).