WO2019122769A1

WO2019122769A1 - Ventilation device with tubes provided with oriented air flow guide means for a motor vehicle heat exchange module

Info

Publication number: WO2019122769A1
Application number: PCT/FR2018/053489
Authority: WO
Inventors: Michael LISSNER; Kamel Azzouz; Amrid MAMMERI
Original assignee: Valeo Systemes Thermiques
Priority date: 2017-12-20
Filing date: 2018-12-20
Publication date: 2019-06-27
Also published as: FR3075323B1; FR3075323A1

Abstract

The invention relates to a ventilation device (2) intended to generate a flow of air towards a heat exchanger (1) of a motor vehicle,comprising ducts (8), intended to have an air flow passing through them, the ducts (8) being provided with at least one air flow passage opening (40), distinct from their ends, at least one duct (8) comprising deflectors (94; 102) for guiding the air flow passing through it towards the at least one opening (40) and configured to divert the air flow (F) with respect to a longitudinal direction of the duct (8), at least one first guides deflector (102) extending, from the vicinity of an opening (40), at a different angle compared to a second deflector. Figure 6.

Description

TUBE VENTILATION DEVICE PROVIDED WITH ORIENTED AIR FLOW GUIDING MEANS FOR A HEAT EXCHANGE MODULE

MOTOR VEHICLE

The present invention relates to a ventilation device for a heat exchange module and a heat exchange module for a motor vehicle.

A heat exchanger generally comprises tubes, in which a coolant is intended to circulate, and heat exchange elements connected to these tubes, often referred to as "fins" or "spacers".

The fins increase the heat exchange surface between the tubes and the ambient air. However, in order to increase the heat exchange between the coolant and the ambient air, it is common that a ventilation device is used in addition to generate a flow of air directed to the tubes and fins.

Such a ventilation device most often comprises a propeller fan, which has many disadvantages.

First, the assembly formed by the propeller fan and its motorization system occupies a large volume.

In addition, the distribution of the air ventilated by the propeller, often placed in front of the center of the heat pipe row, is not homogeneous over the entire surface of the heat exchanger. In particular, certain regions of the heat exchanger, such as the ends of the heat pipes and the corners of the heat exchanger, are not or only slightly reached by the air flow ventilated by the propeller.

Finally, when the start of the ventilation device is not necessary, especially when the ambient air flow created by the movement of the motor vehicle is sufficient to cool the coolant, the blades of the propeller partially mask the air. 'heat exchanger. Thus, a portion of the heat exchanger is not or only slightly ventilated by the ambient air flow in this case, which limits the heat exchange between the heat exchanger and the ambient air flow.

Furthermore, it is known from German patent DE 10 2011 120 865 a motor vehicle having a ventilation device and a heat exchanger, the ventilation device being adapted to generate a flow of air through the heat exchanger. The ventilation device is adapted to create a secondary air flow from a primary flow emitted from one or more annular elements, the secondary air flow being much stronger than the primary air flow. In such a vehicle In the automotive industry, each annular element is supplied with primary air flow by a single fan, arranged outside the annular element, via a channel opening punctually into the annular element. Consequently, the ejected air flow emitted by the annular element is not homogeneous on the contour of the annular element. On the contrary, the air flow emitted is all the more important as it is close to the fan. It follows the creation of a secondary air flow through the heat exchanger which is also inhomogeneous.

Finally, it is known from the application DE 10 2015 205 415 a ventilation device intended to generate an air flow through a heat exchanger comprising a hollow frame and at least one hollow spacer, dividing the surface delimited by the frame. cells. The frame and the spacer (s) are in fluid communication with a feed turbine engine in a flow of air. The turbomachine is disposed outside the frame. The frame and possibly the spacer or spacers are further provided with an ejection opening of the flow of air flowing through them.

Again, the ventilation device does not generate a homogeneous air flow through the heat exchanger. On the contrary, the air flow emitted by the device is all the more important that it is ejected from the ventilation device near the turbomachine.

The invention aims to provide an improved ventilation device.

To this end, the invention proposes a ventilation device intended to generate an air flow towards a motor vehicle heat exchanger, comprising ducts, intended to be traversed by a flow of air, the ducts being provided with at least one passage opening of the air flow, distinct from their ends, at least one duct comprising airflow guiding baffles passing it towards the at least one opening, configured to deflect the flow of air. air relative to a longitudinal direction of the conduit, at least a first guide baffle extending from the vicinity of an opening, at a different angle relative to a second deflector.

Thus, advantageously, the deflectors used to guide the flow of air ejected in different directions. In particular, this can make it possible to direct the flow of air ejected by openings disposed near a longitudinal end of a duct, so that it converges with the air flow ejected by the openings arranged more in the middle from the same conduit. This limits the losses of ejected air flow. Preferably, the ventilation device comprises one or more of the following features, taken alone or in combination:

said first and second guide baffles extending at different angles, are in the vicinity of a longitudinal end of the conduit, for one, and in the vicinity of the middle of the conduit, for the other;

the baffles came from matter with the conduit;

the baffles extend from a leading edge of the conduit;

the deflectors extend over substantially the entire height of the duct;

the deflectors arranged near the middle of the ducts comprise a first planar portion extending from a leading edge of the duct in a direction substantially perpendicular to the longitudinal direction of the duct, and a second flat portion extending from the first planar portion and at an angle to the first planar portion;

a free end of the second flat portion is oriented towards the longitudinal end of the at least one duct closest to the deflector;

the angle between the first planar portion and the second planar portion is greater than or equal to 60 °, preferably greater than or equal to 90 °, and / or less than or equal to 160 °, preferably less than or equal to 120 °;

the duct is provided with means for deflecting the air flow ejected by at least one opening, the said deflection means being preferably convergent; the conduit is provided with partitioning means hermetically separating the conduit in at least two contiguous spaces;

the partitioning means comprise at least one plane partition extending in a plane substantially normal to the longitudinal direction of the conduit and disposed at half the length of the conduit;

the duct comprises, along at least a portion of the duct, means for distributing the flow of air flowing through said duct towards the at least one opening;

the duct has, on at least one section, a section comprising:

- a leading edge;

- a trailing edge opposite the leading edge;

first and second profiles, each extending between the leading edge and the trailing edge,

said at least one opening of the conduit being on the first profile, said at least one aperture being configured such that the flow of air ejected by said at least one aperture flows along at least a portion of the first profile; and

the duct has, on at least one section, a section comprising:

- a leading edge;

a trailing edge, opposite to the leading edge,

a first profile and a second profile, each extending between the leading edge and the trailing edge,

each conduit having:

- At least a first opening on the first profile, configured so that an air flow out of the first opening flows along at least a portion of the first profile; and

at least one second opening on the second profile, configured so that an air flow leaving the second opening flows along at least a portion of the second profile,

the first and second profiles of the conduit being preferably substantially symmetrical with respect to the rope connecting the leading edge and the trailing edge.

According to another aspect, the invention relates to a motor vehicle heat exchange module comprising a heat exchanger having a plurality of tubes, said heat-transfer tubes, in which a fluid is intended to circulate, and a ventilation device such as described above in all its combinations, the ventilation device being adapted to generate a flow of air through the heat exchanger.

The invention will be better understood on reading the description which follows, given solely by way of example and with reference to the drawings in which:

FIG. 1 is a schematic perspective view of an example of a heat exchange module;

FIG. 2 is a more detailed perspective view of a detail of the heat exchange module of FIG. 1;

- Figure 3 is a schematic sectional view along the plane II-II of the heat exchange module of Figure 1;

FIG. 4 is a diagrammatic cross-sectional view of an aerodynamic duct of the ventilation device illustrated in FIG. 1;

FIG. 5 is a schematic view in longitudinal section of a duct aerodynamic ventilation device shown in Figure 1;

FIG. 6 illustrates a detail of FIG. 5;

FIG. 7 illustrates a perspective view of an aerodynamic duct of the ventilation device of FIG. 1; and

FIGS. 8 to 11 illustrate, in cross-section, variants of the aerodynamic duct of the ventilation device illustrated in FIG.

In the various figures, the identical or similar elements, having an identical function or the like, bear the same references. The description of their structure and function is therefore not systematically repeated.

FIG. 1 shows an example of a heat exchange module 10 intended to equip a motor vehicle, with a heat exchanger 1 and equipped with a ventilation device 2.

The heat exchanger 1 comprises, as is more visible in Figure 1, heat transfer ducts 4 in which a fluid is intended to circulate. The fluid here is water or coolant. Heat transfer ducts 4 are here substantially rectilinear and extend in a longitudinal direction. The heat-transfer ducts thus form heat-transfer tubes 4. The heat-transfer tubes 4 are parallel to each other and aligned so as to form a row. The heat pipes 4 are substantially all of the same length.

The heat-transfer ducts 4 each extend between a fluid intake manifold 5 and a fluid evacuation manifold 6, common to all the heat-transfer ducts 4. Preferably, the orifices of the fluid intake manifold 5, in which open the heat pipes 4 are all included in the same foreground. Likewise, the orifices of the fluid evacuation manifold 6 into which the heat transfer ducts 4 open are all included in one and the same second plane, preferably parallel to said first plane.

More particularly, and conventionally in motor vehicle heat exchangers, each heat transfer tube 4 has a substantially oblong cross section, and is delimited by first and second planar walls which are connected to heat exchange fins. For the sake of clarity, the fins are not shown in FIG.

The heat exchange module 10 is equipped with a ventilation device 2 comprising a plurality of ventilation ducts 8 (or aerodynamic duct). The ventilation ducts 8, in the same way as the heat-transfer ducts 4, are substantially rectilinear, so as to form ventilation tubes 8. The ventilation tubes 8 are further parallel to each other and aligned to form a row of ventilation tubes 8. The ventilation tubes 8 are also of the same length. The length of the ventilation tubes 8 is for example substantially equal to the length of the heat-transfer tubes 4.

The ventilation device 2 is intended to generate a flow of air towards the heat-transfer tubes 4.

The heat-transfer tubes 4 and the ventilation tubes 8 may all be parallel to each other, as illustrated in FIG. 1. Thus, the rows of ventilation tubes 8 and of heat-transfer tubes 4 are themselves parallel. In addition, the ventilation tubes 8 may be arranged so that each of them is opposite a heat-transfer tube 4.

The number of ventilation tubes 8 is adapted to the number of heat-transfer tubes 4. For example, for a conventional heat exchanger 1, the ventilation device 2 may comprise, for example, at least ten ventilation tubes 8, preferably at least 15 tubes. 8, more preferably at least twenty-four ventilation tubes 8 and / or at most fifty ventilation tubes 8, preferably at most thirty-six ventilation tubes 8, more preferably at most thirty ventilation tubes 8. The heat exchanger 1 may for example comprise between sixty and seventy heat-transfer tubes 4.

The tubes and the number of ventilation tubes 8 of the ventilation device 2 may be such that a minimum air passage section between the tubes of the ventilation device, defined in a plane substantially perpendicular to the flow of air through the ventilation device. Heat exchanger 1 is between 25 and 50% of the surface, defined in a plane perpendicular to the flow of air through the heat exchanger, between two extreme heat transfer tubes.

Preferably, the front surface of the ventilation tubes 8, measured in a plane substantially perpendicular to the air flow passing through the heat exchanger 1, is less than 85% of the front surface occupied by the heat-transfer tubes 4.

Moreover, in order to limit the volume occupied by the heat exchange module comprising the heat exchanger 1 and the ventilation device 2, while obtaining heat exchange performance similar to that of a ventilation device with a helix, the row of ventilation tubes 8 can be arranged at a distance less than or equal to 150 mm from the row of heat-transfer tubes 4, preferably less than or equal to 100 mm. This distance is preferably greater than or equal to 5 mm, preferably greater than 40 mm. Indeed, a too short distance between the ventilation tubes 8 and the heat-transfer tubes 4 may not allow a homogeneous mixture of air flow ejected from the ventilation tubes 8 with the induced air flow. An inhomogeneous mixture does not allow homogeneous cooling of the heat transfer tubes 4 and induces high pressure losses. Too great a distance may not allow to set up the assembly formed by the ventilation device and the heat exchange device in a motor vehicle without requiring a suitable design of the power unit and / or other motor vehicle bodies present in the vicinity of the heat exchange module.

Similarly, again to limit the volume occupied by the heat exchange module 10, it can be ensured that the height of the row of ventilation tubes 8 (the term height here referring to the dimension corresponding to the direction according to which the ventilation tubes 8 are aligned) is substantially equal to or less than that of the height of the row of heat transfer tubes 4. For example, the height of the row of heat transfer tubes 4 being 431 mm, it can be ensured that the height of the row of ventilation tubes 8 is substantially equal to or less than this value.

The ventilation device 2 further comprises a supply device supplying air to the ventilation tubes 8, not visible in FIG. 2, via an air intake manifold 12, preferably via two inlet manifolds. air 12.

The air propulsion means supplying air to the ventilation device 2 are for example a turbomachine, supplying the two air intake manifolds 12, arranged at each end of the ventilation device 1, via a respective port 13. This turbomachine is advantageously distinct from the propeller fan 3.

In the example illustrated in Figure 2, the ports 13 are substantially in the middle of the air intake manifolds 12. Alternatively or additionally, the ports 13 are at a longitudinal end 12a and / or at the other longitudinal end 12b of each air intake manifold 12 and / or arranged along the length of the air intake manifolds 12. Alternatively, also, a turbomachine can feed a single intake manifold 12 and not two. One or more turbomachines may also be implemented to supply each air intake manifold 12 or all the air intake manifolds 12.

According to another embodiment, also, the turbine engine or turbomachines are received in one or in each air intake manifold 12, in particular in the vicinity one or each longitudinal end 12a, 12b of the or each air intake manifold.

Here, however, the air propulsion means are remote from the ventilation tubes 8, outside the air intake manifolds 12 through which the air propulsion means feed airflow the ventilation tubes 8. The or each turbomachine forming the air propulsion means may not be directly adjacent to the air intake manifolds 12. On the contrary, it may be advantageous to be able to remotely transport the turbine engine (s). ventilation tubes 8, in particular through the intake manifolds 12 and, optionally, a suitable air flow circuit putting in fluid communication the port (s) 13 of the air collector (s) 12 to one or more turbomachines .

Each air intake manifold 12 may for example be tubular. In the embodiment of Figure 1, the air intake manifolds 12 extend in the same direction, which is here perpendicular to the elongation direction (or longitudinal direction) of the heat transfer tubes 4 and ventilation 8.

As can be seen in FIG. 1, the air intake manifold 12 comprises a plurality of air ejection orifices each made at one end of a respective tubular portion, each ejection port of air being connected to a single ventilation tube 8, and more particularly to the end of the ventilation tube 8.

Advantageously, each air intake manifold 12 is devoid of any other opening than the orifices and the ports 13 mentioned above. In particular, the collector 12 is preferably devoid of an opening directed towards the heat exchanger 1, which in this case would make it possible to eject a part of the air flow passing through the air collector 12, directly in the direction of the heat exchanger 1, without traversing at least a portion of a ventilation tube 8. Thus, all the air flow created by the turbine engine or turbomachines through the or the air collectors 12, can be divided between substantially all ventilation tubes 8. This also allows a more homogeneous distribution of this air flow.

It may be noted here that the shape of the ventilation tubes 8 is a priori independent of the configuration of the air intake manifolds.

According to the example of Figures 2 to 4, an aerodynamic tube 8 has on at least a portion, preferably over substantially its entire length, a cross section as illustrated with a leading edge 37, a trailing edge 38 opposite at the leading edge 37 and, here, disposed opposite heat pipes 4, and a first and a second profiles 42, 44, each extending between the leading edge 37 and the trailing edge 38. The leading edge 37 is for example defined as the point at the front of the section of the aerodynamic tube 8 where the radius curvature of the section is minimal. The front of the section of the aerodynamic tube 8 can be defined as the portion of the section of the aerodynamic tube 8 which is opposite - that is to say which is not in front of - of the heat exchanger 1. Similarly, the trailing edge 38 may be defined as the point at the rear of the section of the aerodynamic tube 8 where the radius of curvature of the section is minimal. The rear of the section of the aerodynamic tube 8 can be defined, for example, as the portion of the section of the aerodynamic tube 8 which faces the heat exchanger 1.

The distance c between the leading edge 37 and the trailing edge 38 is for example between 16 mm and 26 mm. This distance is here measured in a direction perpendicular to the alignment direction of the row of aerodynamic tubes 8 and the longitudinal direction of the aerodynamic tubes 8

In the example of Figures 2 to 4, the leading edge 37 is free. In these figures also, the leading edge 37 is defined on a parabolic portion of the section of the aerodynamic tube 8.

The aerodynamic tube 8 illustrated in FIGS. 2 to 4 also comprises at least one opening 40 for ejecting a stream of air passing through the aerodynamic tube 8, outside the aerodynamic tube 8 and the air intake manifold 12, in particular substantially in the direction of the heat exchanger 1. The opening or each opening 40 is for example a slot in an outer wall 41 of the aerodynamic tube 8, the slot or slots extending for example in the direction of elongation of the tube aerodynamic 8 in which they are made. The total length of the opening 40 or openings may be greater than 90% of the length of the aerodynamic tube. Each opening 40 is distinct from the ends of the aerodynamic tube 8, through which the aerodynamic tube 8 opens into an air manifold 12. Each opening 40 is also outside the air intake manifold 12. The shape slot makes it possible to constitute a large air passage in the direction of the heat exchanger 1 without greatly reducing the mechanical strength of the aerodynamic tubes 8.

In the following only describes an opening 40 being understood that each opening 40 of the aerodynamic tube 8 may be identical to the opening 40 described.

The opening 40 is for example disposed near the leading edge 37. In the example of Figure 4, the opening 40 is on the first profile 42. In this example, the second profile 44 is devoid of opening 40. The opening 40 in the first profile 42 is configured so that the flow of air ejected through the opening 40 flows along at least a portion of the first profile 42.

The aerodynamic tubes 8 of the ventilation device 2 can be oriented alternately with the first profile 42 or the second profile 44 facing upwards. Thus, alternatively, two adjacent aerodynamic tubes 8 are such that their first profiles 42 are vis-à-vis or, conversely, their second profiles 44 are vis-à-vis. The distance between two aerodynamic tubes 8 neighbors whose second profiles 44 are vis-à-vis is less than the distance between two aerodynamic tubes 8 neighbors whose first profiles 42 are vis-à-vis. The pitch between two adjacent aerodynamic tubes or the distance between the center of the geometrical section of a first aerodynamic tube 8 and the center of the geometrical section of a second aerodynamic tube 8, such as the first profile 42 of the first aerodynamic tube 8 either vis-à-vis the first profile 42 of the second aerodynamic tube 8, measured in the direction of alignment of the aerodynamic tubes 8 is greater than or equal to 15 mm, preferably greater than or equal to 20 mm, and / or less or equal to 30 mm, preferably less than or equal to 25 mm.

For each pair of aerodynamic tubes 8 whose openings 40 are facing each other, the air flows ejected by these openings 40 thus create an air passage 46 in which a part, called induced air I, of the ambient air A is driven by suction.

It should be noted here that the flow of air ejected through the openings 40 runs along at least part of the first profile 42 of the aerodynamic tube 8, for example by Coanda effect. Taking advantage of this phenomenon, it is possible, thanks to the entrainment of the ambient air in the created air passage, to obtain a flow of air sent to the heat pipes identical to that generated by a propeller fan. while consuming less energy.

Indeed, the air flow sent to the row of heat transfer tubes 4 is the sum of the air flow ejected by the slots and induced air. Thus, it is possible to implement a turbomachine of reduced power compared to a conventional propeller fan, generally implemented in the context of such a heat exchange module.

A first profile 42 having a Coanda surface also makes it possible not to have to orient the openings 40 directly towards the heat-transfer tubes 4, and thus to limit the size of the aerodynamic tubes 8. It is thus possible to maintain a passage section. more important between aerodynamic tubes 8, this which promotes the formation of a greater induced air flow.

The opening 40 is, in Figure 4, delimited by lips 40a, 40b. The spacing e between the lips 40a, 40b, which defines the height of the opening 40, may be greater than or equal to 0.3 mm, preferably greater than or equal to 0.5 mm, more preferably greater than or equal to 0.7 mm and / or less than 2 mm, preferably less than or equal to 1.5 mm, more preferably less than 0.9 mm, more preferably less than or equal to 0.7 mm. The height of the slot is the size of this slot in the direction perpendicular to its length. The lower the height of the slot 40, the greater the speed of the air flow ejected by this slot. A high speed of ejected airflow results in a high dynamic pressure. This dynamic pressure is then converted into static pressure in the mixing zone of the air flow ejected by the slot 40 and the induced air flow. This static pressure makes it possible to overcome the pressure losses due to the presence of the heat exchanger downstream of the ventilation device, in order to ensure a suitable flow of air through the heat exchanger. These pressure losses due to the heat exchanger vary in particular as a function of the heat pipe pitch and the pitch of the fins of the heat exchanger, as well as the number of heat exchange modules that can be superimposed. in the heat exchanger. However, a slot height too low induces high pressure losses in the ventilation device, which involves using an air propulsion device or several oversized (s). This can lead to additional cost and / or create a space incompatible with the space available in the vicinity of the heat exchange module in the motor vehicle.

The outer lip 40a here consists of the extension of the wall of the aerodynamic tube 8 defining the leading edge 37. The inner lip 40b is constituted by a curved portion 50 of the first profile 42. An end 51 of the inner lip 40b can extend, as illustrated in Figure 11, in the direction of the second profile 44, beyond a plane L normal to the free end of the outer lip 40a. In other words, the end 51 of the inner lip 40b can extend, towards the leading edge 37, beyond the normal plane L at the free end of the outer lip 40a. The end 51 can then contribute to directing the flow of air flowing in the aerodynamic tube 8 towards the opening 40.

The opening 40 of the aerodynamic tube 8 can be configured so that a flow of air flowing in this aerodynamic tube 8 is ejected through this opening 40, flowing along the first profile 42 substantially to the trailing edge 38 of the tube Aerodynamic 8. The flow of airflow along the first profile 42 may result from the Coanda effect. It is recalled that the Coanda effect is an aerodynamic phenomenon that results in the fact that a fluid flowing along a surface at a short distance from it tends to outcrop or even hang on it.

To do this, here the maximum distance h between the first 42 and the second 44 profiles, measured according to an alignment direction of the aerodynamic tubes 8, is downstream of the opening 40. The maximum distance h may be greater than 10 mm, preferably greater than 11 mm and / or less than 20 mm, preferably less than 15 mm. Here, by way of example, the maximum distance h is substantially equal to 11.5 mm. A height h too low can cause significant pressure losses in the aerodynamic tube 8 which could require to implement a turbomachine more powerful and therefore more voluminous. For the same value of the distance between the aerodynamic tubes 8, measured according to the direction of alignment of the aerodynamic tubes, a height h too large limits the passage section between the aerodynamic tubes for the induced air flow. The total air flow directed to the heat exchanger is then also reduced.

The first profile 42 here comprises a curved portion 50 whose apex defines the point of the first profile 42 corresponding to the maximum distance h. The curved portion 50 may be disposed downstream of the opening 40 in the direction of ejection of the air flow. In particular, the convex portion 50 may be contiguous with the inner lip 40b delimiting the opening 40.

Downstream of the curved portion 50 in the direction of ejection of said air flow through the opening 40, the first profile 42 of the aerodynamic tube 8 of the example of Figure 4 comprises a first portion 52 substantially straight. The second profile 44 comprises, in the example illustrated in FIG. 4, a substantially rectilinear portion 48, preferably extending over a majority of the length of the second profile 44. In the example of FIG. 4, the length 1 of the first rectilinear part 52, measured in a direction perpendicular to the longitudinal direction of the aerodynamic tube 8 and the alignment direction of the row of aerodynamic tubes, may be greater than or equal to 30 mm, preferably greater than or equal to 40 mm, and / or less than or equal to 50 mm. A relatively large length of this first rectilinear part is desired in particular for guiding the air flow ejected from the opening 40, which makes it possible to ensure greater suction of air. The length of this first rectilinear part is however limited because of the corresponding size of the device of ventilation and its consequences on the packaging of the ventilation device or the heat exchange module.

In this case, the first rectilinear portion 52 of the first profile 42 and the straight portion 48 of the second profile 44 may form a non-flat angle Q. The angle Q thus formed may in particular be greater than or equal to 5 °, and / or less than or equal to 20 °, more preferably substantially equal to 10 °. This angle of the first rectilinear portion 52 with respect to the rectilinear portion 48 of the second profile 44 makes it possible to accentuate the expansion of the flow of air ejected by the opening 40 and undergoing the Coanda effect forcing it to follow the first profile 42 , this accentuated relaxation to increase the induced air flow. An angle Q too great, however, may prevent the realization of the Coanda effect, so that the flow of air ejected through the opening 40 may not follow the first profile 42 and, therefore, not to be oriented correctly towards the heat exchanger 2.

The first profile 42 may comprise, as illustrated in FIG. 4, a second rectilinear portion 38a, downstream of the first straight portion 52, in the direction of ejection of the air flow, the second straight portion 38a extending substantially parallel to the rectilinear portion 48 of the second profile 44. The first profile 42 may also include a third straight portion 54, downstream of the second straight portion 38a of the first profile 42. The third straight portion 54 may form a non-flat angle with the rectilinear portion 48 of the second profile 44. The third rectilinear portion 54 may extend, as illustrated, substantially to a rounded edge connecting the third rectilinear portion 54 of the first profile 42 and the straight portion 48 of the second profile 44. The edge rounded can define the trailing edge 38 of the cross section of the aerodynamic tube 8.

The straight portion 48 of the second profile 44 extends in the example of Figure 4 over the majority of the length c of the cross section. This length c is measured in a direction perpendicular to the longitudinal direction of the aerodynamic tubes 8 and the alignment direction of the row of the aerodynamic tubes 8. This direction corresponds, in the example of Figure 4, substantially to the direction of the flow of the induced air flow. In this first exemplary embodiment, the length c of the cross section (or width of the aerodynamic tube 8) may be greater than or equal to 50 mm and / or less than or equal to 70 mm, preferably substantially equal to 60 mm. Indeed, the inventors have found that a relatively large length of the cross section of the aerodynamic tube makes it possible to more effectively guide the flow of air ejected through the opening 40 and the induced air flow, which mixes with this airflow ejected. However, too great a length of the cross section of the aerodynamic tube 8 poses a problem of packaging of the ventilation device 2. In particular, the size of the heat exchange module can then be too large compared to the place that is available in the motor vehicle in which it is intended to be mounted. The packaging of the heat exchange module or the ventilation device can also be problematic in this case.

Moreover, as illustrated in FIG. 4, the second rectilinear portion 38a of the first profile 42 and the portion 38b of the rectilinear portion 48 of the second profile 44 facing it are parallel. For example, the distance f between this second rectilinear portion 38a and the portion 38b of the rectilinear portion 48 of the second profile 44 may be greater than or equal to 2 mm and / or less than or equal to 10 mm, preferably less than or equal to 5 mm. mm.

FIG. 4 further illustrates that the cross section (or geometrical section) of the aerodynamic tube 8 delimits a passage section S for the flow of air passing through the aerodynamic tube 8. This passage section S is here defined by the walls of the aerodynamic tube 8 and the segment extending in the alignment direction of the aerodynamic tubes 8 between the second profile 44 and the end of the end 51 of the inner lip 40b. This passage section may have an area greater than or equal to 150 mm ² , preferably greater than or equal to 200 mm ² , and / or less than or equal to 700 mm ² , preferably less than or equal to 650 mm ² . A passage section of the air flow in the aerodynamic tube 8 limits the pressure losses which would have the consequence of having to oversize the turbomachine used to obtain an air flow ejected by the desired opening 40. However, a large passage section induces a large size of the aerodynamic tube 8. Thus, with fixed pitch aerodynamic tubes, a larger passage section may affect the passage section of the induced air flow between the aerodynamic tubes 8 , thus not making it possible to obtain a satisfactory total flow of air directed towards the heat-transfer tubes 4.

In order to block as little as possible the flow of air towards the heat-transfer tubes 4 and the fins, the ventilation device 2 provided with such aerodynamic tubes 8 is advantageously arranged so that each aerodynamic tube 8 is vis-à-vis 4f of the front face connecting the first 4a and second 4b planar walls of a heat pipe 4 corresponding. More particularly, the trailing edge 38 of each aerodynamic tube 8 is included in the volume defined by the first and second longitudinal plane walls of the heat pipe 4 corresponding. Preferably, the second rectilinear portion 38a of the first profile and the rectilinear portion 48 of the second profile 44 are respectively contained in the same plane as the first longitudinal plane wall and the second longitudinal plane wall of the heat pipe 4 corresponding.

In particular, the distance f between the second straight portion 38a of the first profile 42 and the portion 38b of the rectilinear portion 48 of the second profile 44 facing it is substantially equal to the distance separating the first longitudinal wall and the second longitudinal wall. heat transport tube 4 vis-à-vis which the aerodynamic tube 8 is disposed. For example, this distance f is greater than or equal to 2 mm and / or less than or equal to 10 mm, preferably less than or equal to 5 mm.

In other embodiments, the distance f between the second rectilinear portion 38a of the first profile 42 and the portion 38b of the rectilinear portion 48 of the second profile 44, which faces it, may, however, be less than the distance separating the first longitudinal wall and the second longitudinal wall of the heat transport tube vis-à-vis the aerodynamic tube 8 is disposed.

Two heat transfer tubes 4 may be contained in the volume defined by the air passage defined by two aerodynamic tubes 8 neighbors. However, it can be envisaged that a single heat-transfer tube 4, or three or four heat-transfer tubes 4 are contained in this volume. Conversely, it can be envisaged that an aerodynamic tube 8 is disposed opposite each heat-carrying tube 4.

Moreover, as is more particularly visible in FIGS. 5 and 6, at least one aerodynamic tube 8 comprising guiding baffles 94 of the air flow making it possible to orient the flow of air at its exit from the openings 40. these guiding baffles 94 serve to guide the flow of air passing through the aerodynamic tube 8, and are configured to deflect the air flow with respect to a longitudinal direction of the aerodynamic tube 8. It is thus possible to increase the efficiency of the ventilation provided by the ventilation device 2 and to limit the pressure drop.

More specifically, here, the guide baffles 94 located in the vicinity of the middle of the aerodynamic tube 8 are configured so that the flow of air flows, at its exit from the aerodynamic tube 8, in a direction substantially normal to the plane of the opening 40, perpendicular to the longitudinal direction of the aerodynamic tubes 8.

To do this, the guiding baffles 94 comprise a first planar portion 96 extending, from the leading edge 37, in a direction substantially perpendicular to the longitudinal direction of the aerodynamic tube 8, and a second planar portion 98 extending from the first planar portion 96 and at an angle to the first planar portion 96. For example, the angle between the first planar portion 96 and the second flat portion 98 is between 100 ° and 120 °, preferably between 105 ° and 115 °.

In order to further improve the guiding of the air flow, the free end of the second flat portion 96 is oriented towards the longitudinal end of the aerodynamic tube 8 closest to the deflector 94.

In order to further limit the turbulence in the aerodynamic tube 8 and the pressure losses by recirculation, the aerodynamic tube 8 is provided with filling means 100 filling a portion of the aerodynamic tube 8 so as to define an EC space of the aerodynamic tube 8 in which the airflow can not flow.

Moreover, here, the deflectors 102 situated in the vicinity of the longitudinal ends of the aerodynamic tube 8 are made in the form of simple flat walls, which extend in distinct directions, these directions being in particular distinct in the direction of the first planar portion 96 baffles 94 located in the vicinity of the middle of the aerodynamic tube 8. Thus, these deflectors 102 extend in directions that are not perpendicular to a longitudinal direction of the aerodynamic tube 8. These baffles are used to guide the air flow ejected so that it converges to the flow of air ejected through the openings 40 arranged more in the middle of the aerodynamic tube 8. This can be particularly useful when the ventilation device 2 is wider than the exchanger 1 towards which it directs the flow of air, in order to limit the flow of ejected air lost and limit the by maximizing the passage section at the slot, i.e., not being used to cool the heat exchanger 1.

Here, the four deflectors 102 located closest to the longitudinal end of the aerodynamic tube all extend at a distinct angle. These angles are increasing from the longitudinal end of the aerodynamic tube 8 towards the middle of the aerodynamic tube 8.

The deflectors 94, 102 are advantageously integral with the aerodynamic tube 8. The deflectors 94, 102 are preferably arranged regularly along the aerodynamic tubes 8.

In order to improve the guiding of the air flow, the deflectors 94, 102 extend over substantially the entire height of the aerodynamic tubes 8. The deflectors 94, 102 advantageously extend from the leading edge 37 in order to limit the pressure drops of the ejected air flow.

In addition or alternatively, as illustrated in Figure 7, the aerodynamic tubes 8 are provided on their outer surface with means 104 for deflecting the air flow ejected by at least one opening. These deflection means 104 are also formed by walls, extending advantageously from the leading edge 37 of the aerodynamic tubes 8 or, at the very least, from the openings 40. These walls 104 form convergent channels 106 which guide the air flow ejected by the apertures 40 closest to the longitudinal ends of the aerodynamic tube 8 so that this air flow converges with the flow of air ejected through openings 40 arranged more centrally of the aerodynamic tube 8.

These walls 104 are preferably integral with the aerodynamic tube

8.

Figures 8 to 11 illustrate variants of the ventilation device 2 and, more specifically, the ventilation tubes 8 of the ventilation device 2.

In all these examples, the aerodynamic ducts 8 are substantially rectilinear, parallel to each other and aligned so as to form a row of aerodynamic tubes 8.

However, the first and second profiles 42, 44 of each aerodynamic tube 8 are, according to the examples of FIGS. 8 to 10, symmetrical with respect to a plane CC, or chord plane, passing through the leading edge 37 and the edge leakage 38 of each aerodynamic tube 8.

As the first and second profiles 42, 44 are symmetrical, each of these profiles 42, 44 is provided with an opening 40. Thus, at least a first opening 40 is formed on the first profile 42, which is configured so that a the air flow exiting the first opening 42 flows along at least a portion of the first profile 42. Likewise, at least a second opening 40 is present on the second profile 44, which is configured so that a airflow exiting the second opening 40 flows along at least a portion of the second profile 44. As for the example of Figure 4, this can be achieved here by implementing the Coanda effect.

For the same reasons as those given for the example of FIGS. 2 to 4, the distance c between the leading edge 37 and the trailing edge 38 can also, in these examples, be greater than or equal to 50 mm and / or less than or equal to 80 mm. In particular, the length c may be equal to 60 mm. The openings 40 are similar to those of the example of FIG. 4. In particular, the distance e between the inner and outer lips 40b and 40a of each opening 40 may be greater than or equal to 0.3 mm, preferably greater than or equal to 0.5 mm, more preferably greater than or equal to 0.7 mm, and / or less than or equal to 2 mm, preferably less than or equal to 1.5 mm, more preferably less than or equal to 0.9 mm and more preferably still less than or equal to 0.7 mm.

The fact that the profiles 42, 44 are symmetrical with respect to the chord plane CC passing through the leading edge 37 and the trailing edge 38 of the aerodynamic tube 8 makes it possible to limit the obstruction to the air flow between the device of FIG. ventilation 2 and the heat pipes 4, while creating more air passages in the volume available in front of the heat pipes 4.

In other words, contrary to the embodiment of Figure 4, an air passage leading to ambient air is created between each pair of aerodynamic tubes 8 neighbors, made according to one of Figures 8 to 10.

The pitch between two adjacent aerodynamic tubes 8 may, in this case, be greater than or equal to 15 mm, preferably greater than or equal to 20 mm, more preferably greater than or equal to 23 mm and / or less than or equal to 30 mm, preferably less than or equal to 25 mm, more preferably less than or equal to 27 mm. Indeed, if the pitch between the aerodynamic tubes 8 is lower, the induced air flow is limited by a passage section between the weak aerodynamic tubes. On the contrary, if the pitch is too large, the ejected airflow does not create an induced air flow over the entire pitch between the neighboring aerodynamic tubes.

The pitch between two adjacent aerodynamic tubes 8 can in particular be defined as the distance between the center of the cross section of two adjacent aerodynamic tubes 8 or, more generally, as the distance between a reference point on a first aerodynamic tube 8 and the point corresponding to the reference point, on the nearest aerodynamic tube 8. The reference point may especially be one of the leading edge 37, the trailing edge 38 or the top of the curved portion 50.

The distance between the aerodynamic tubes 8 and the heat-transfer tubes 4 can in particular be chosen greater than or equal to 5 mm, preferably greater than or equal to 40 mm, and / or less than or equal to 150 mm, preferably less than or equal to 100 mm. . Indeed, the peak speed of the air velocity profile in the vicinity of the profile, tends to be reduced by departing from the opening 40 in the aerodynamic tube. A lack of peak translates a homogeneous mixture of the air flow ejected by the opening 40 and the induced air flow. It is preferable that such a homogeneous mixture is made before the airflow reaches the aerodynamic tubes. Indeed, a flow of air incident on the heat transfer tubes, heterogeneous, does not allow optimal cooling of the heat pipes and induces greater pressure losses. However, the distance between the aerodynamic tubes and the heat transfer tubes is preferably contained to limit the size of the cooling module.

In the example illustrated in FIG. 8, the first and second profiles 42, 44 of the aerodynamic tube 8 converge towards the trailing edge 38 so that the distance separating the first and second profiles 42, 44 decreases strictly towards the edge of the airfoil. leak 38 from a point of these first and second profiles 42, 44 corresponding to the maximum distance h between these two profiles, these points of the first and second profiles 42, 44 being downstream of the openings 40 in the direction of flow the flow of air ejected through the opening 40. Preferably, the first and second profiles 42, 44 each form an angle of between 5 and 10 ° with the symmetry rope CC of the cross section of the aerodynamic tube 8.

As a result, contrary to the example of FIG. 4, the aerodynamic profile of FIG. 8 does not include a portion delimited by first and second parallel opposed plane walls. This has the advantage of limiting the screen along the aerodynamic profile of the aerodynamic tube 8.

For example, the maximum distance h between the first profile 42 and the second profile 44 may be greater than or equal to 10 mm and / or less than or equal to 30 mm. In particular, this maximum distance h can be equal to 11.5 mm. In the example shown in FIGS. 12 to 14, this distance becomes zero at the trailing edge 38.

In the example illustrated in FIG. 9, the trailing edge 38 is formed by the vertex joining two straight symmetrical portions 60 of the first profile 42 and the second profile 44 of each aerodynamic tube 8. According to the variant of FIG. trailing edge 38 is the point of the cross section of the aerodynamic tube 8 located closest to the heat exchanger. In other words, the angle formed by the two rectilinear portions 60 is less than 180 °, especially less than 90 °.

On the contrary, in the variant of FIG. 10, the trailing edge 38 is disposed between the two rectilinear portions 38a, 38b of the first and second profiles 42, 44. In other words, the angle formed by the rectilinear portions 60 is here greater than 90 °, especially greater than 180 °.

Each ventilation tube 8 may also take the form illustrated in FIG. 11. According to this figure, each ventilation tube 8 has a plurality of openings 16 for the passage of an air flow passing through the tube 8. The openings 16 ventilation tubes 8 are located outside the air collectors 12. More precisely, here, the openings

16 are oriented substantially in the direction of the heat exchanger 1, and even more precisely, substantially in the direction of the heat-transfer tubes 4, the slots 16 being for example disposed opposite the heat-transfer tubes 4 or fins housed between the heat pipes.

Each ventilation tube 8 opens into a separate orifice of each manifold 12. Thus, each air manifold 12 has as many orifices as it receives ventilation tubes 8, a ventilation tube 8 being received in each of the orifices of the air collector 12. This allows a more homogeneous distribution of the air flow passing through each air collector 12, in the different ventilation tubes 8.

According to this example of FIG. 11, again, except at their air intake inlet ends, which have a substantially circular cross-section, the ventilation tubes 8 have a substantially oblong cross section, interrupted by the openings 16.

The choice of this form allows an easy manufacture of the ventilation tubes 8 and gives good mechanical strength to the ventilation tubes 8. In particular, such ventilation tubes 8 can be obtained by folding an aluminum foil for example, but also by molding, overmolding, or by printing in three dimensions metal or plastic.

More specifically, the cross section of the ventilation tubes 8 has a substantially elliptical shape whose small axis corresponds to the height of the ventilation tubes 8 and the major axis to the width of the ventilation tubes 8 (the terms height and width in front of hear from the orientation of Figure 11). For example, the small axis h of the ellipse is about 11 mm.

To increase the flow of air ejected to the heat exchanger 1 through the openings 16, the openings 16 are constituted by slots in the wall

17 of the ventilation tube 8, these slots 16 extending in the direction of extension of the ventilation tube 8. This slot form allows to form a large air passage, while maintaining a satisfactory mechanical strength of the tubes 8. In order to achieve the greatest possible airflow, the openings 16 extend over a large part of the length of the ventilation tube 8, preferably over a total length corresponding to at least 90% of the length of the ventilation tube 8.

The openings 16 are here delimited by guide lips 18 projecting from the wall 17 of the ventilation tube 8.

Because they protrude from the wall 17 of each ventilation tube 8, the guide lips 18 guide the air ejected through the opening 16 from the inside of the ventilation tube 8 towards the heat exchanger 1.

The guide lips 18 are preferably flat and substantially parallel. For example, they are spaced from each other by a distance of about 5 mm and have a width (the term width to be considered in view of the orientation of Figure 4), between 2 and 5 mm. The guide lips 18 advantageously extend over the entire length of each opening 16.

The guide lips 18 are preferably integral with the ventilation tube 8. The guide lips 18 are for example obtained by folding the wall

17 of the ventilation tube 8.

Moreover, the openings 16 are also delimited, in the direction of the length of the ventilation tubes 8, by reinforcing elements 20 of the ventilation tubes 8. The reinforcing elements 20 make it possible to maintain the width of the openings 16 constant. this is achieved because the reinforcing elements extending between the two guide lips 18 extend on either side of each opening 16. The reinforcing elements 20 preferably extend in a plane substantially normal to the elongation direction of the ventilation tubes 8, in order to maintain the greatest possible, the section of the openings 16 allowing the passage of the air flow. The reinforcing elements 20 are advantageously evenly distributed along the length of the ventilation tubes 8. In the example illustrated in FIGS. 2 and 3, each ventilation tube 8 comprises seven reinforcing elements 20. Of course, this number is in no way limiting.

The invention is not limited to the exemplary embodiments presented and other embodiments will become clear to those skilled in the art. In particular, the different examples can be combined, as long as they are not contradictory.

Claims

Ventilation device (2) for generating a flow of air towards a heat exchanger (1) of a motor vehicle, comprising ducts (8), intended to be traversed by a flow of air, the conduits (8) being provided with at least one opening (40) for passage of the flow of air, distinct from their ends, at least one duct (8) comprising guide baffles (94; 102) of the air flow passing through the at least one aperture (40), configured to deflect the airflow (F) from a longitudinal direction of the conduit (8), at least one first guide deflector (102) extending from the vicinity of an opening (40), at a different angle relative to a second deflector.

2. A ventilation device (2) according to claim 1, wherein said first and second guide baffles (102) extending at different angles, are in the vicinity of a longitudinal end of the duct (8), for the one, and in the vicinity of the middle of the duct (8), for the other.

3. Ventilation device (2) according to claim 1 or 2, wherein the baffles (94; 102) are integral with the conduit (8).

4. Ventilation device (2) according to one of the preceding claims, wherein the baffles (94; 102) extend from a leading edge (37) of the conduit (B).

A ventilation device (2) according to any one of the preceding claims, wherein the baffles (94; 102) extend over substantially the entire height of the conduit (8).

6. ventilation device (2) according to any one of the preceding claims, wherein the baffles (94) formed in the vicinity of the middle of the ducts (8) comprise a first planar portion (96) extending from a leading edge (37) of the conduit (8), in a direction substantially perpendicular to the longitudinal direction of the conduit (8), and a second planar portion (98) extending to from the first planar portion (96) and at an angle to the first planar portion

(100).

7. Ventilation device (2) according to claim 6, wherein a free end of the second planar portion (98) is oriented towards the longitudinal end of the at least one duct (8) closest to the deflector (94).

8. Ventilation device (2) according to claim 6 or 7, wherein the angle between the first planar portion (96) and the second planar portion (98) is greater than or equal to 60 °, preferably greater than or equal to 90 °, and / or less than or equal to 160 °, preferably less than or equal to 120 °.

9. Ventilation device (2) according to any one of the preceding claims, wherein the conduit (8) is provided with means (104) for deflecting the flow of air ejected by at least one opening, said means of deflection preferably being convergent.

10. A motor vehicle heat exchange module comprising a heat exchanger having a plurality of tubes, said heat-transfer tubes (4), wherein a fluid is intended to circulate, and a ventilation device (2) according to any one of preceding claims, the ventilation device (2) being adapted to generate a flow of air through the heat exchanger (1).