EP2726804B1 - Heat exchanger, particularly for a motor vehicle - Google Patents

Description

The invention relates to a heat exchanger particularly for a motor vehicle according to the preamble of claim 1. Such an exchanger is known, for example, from the document EP 1 903 293 A2 . A preferred field of application of the invention is that of supercharged engines for a motor vehicle, which use a heat exchanger called "charge air cooler" to cool the charge air.

Indeed, supercharged or turbocharged heat engines, particularly diesel engines, are powered by an underpressure air called "supercharging air" from a compressor or a turbo-compressor. As a result of its compression, this air is at a temperature too high and it is desirable for proper operation of the engine to cool before admission to the engine.

For this purpose, a charge air cooler is conventionally used. This chiller has the function of cooling the supercharging air by heat exchange with another fluid such as outside air or a cooling liquid such as glycol water.

Several structures are known for such exchangers or coolers. In particular, there is known a heat exchanger comprising a heat exchange bundle mounted in a housing or housing. The heat exchange bundle comprises for example a stack of parallel plates or tubes arranged in parallel to transport the first fluid while a second fluid flows between the tubes. The casing receiving this heat exchange bundle is generally open at both ends to be connected to fluid distribution boxes: an input box and an output box.

The circulation of the two fluids is important for the performance of the heat exchanger.

According to a known solution, one of the fluids or the two fluids is circulated through disrupters or turbulators in order to increase the heat exchange surfaces between the two fluids.

Moreover, the current trend in the automotive field, is to decrease the size of such heat exchangers. However, reducing the size of the exchanger can reduce the exchange surface between the two fluids and thus impair the performance of the exchanger.

The invention aims to further improve the quality of heat exchange between the two fluids with a smaller footprint.

For this purpose, the subject of the invention is a heat exchanger according to claim 1. The "U" circulation of the two fluids makes it possible to improve the heat exchange performance with a reduced space exchanger.

• lesdits premier et second fluides circulent à contre-courant;
• ledit échangeur comporte une boîte collectrice commune divisée par ladite cloison en deux compartiments de façon à former d'une part ladite boîte d'entrée et d'autre part ladite boîte de sortie;
• la boîte collectrice d'entrée et la boîte collectrice de sortie du premier fluide sont réalisées par deux pièces distinctes;
• ledit faisceau comporte un empilement de tubes dont au moins deux tubes sont joints, de sorte que les surfaces latérales desdits tubes joints se situent sensiblement en vis-à-vis de la séparation entre lesdites tubulures, et que ladite cloison séparant lesdites boîtes collectrices se situe sensiblement en vis-à-vis de la jonction entre lesdits tubes joints;
• la boîte collectrice intermédiaire communiquant avec l'ensemble desdits premiers canaux, est disposée sur une troisième face dudit faisceau opposée à ladite première face, pour la circulation en « U » du premier fluide;
• ledit compartiment intermédiaire communiquant avec l'ensemble desdits seconds canaux, pour la circulation en « U » du second fluide, est disposé sur une extrémité de ladite paroi, opposée auxdites tubulures;
• ledit faisceau présente une forme générale sensiblement parallélépipédique avec deux faces d'extrémité, deux petites faces latérales et deux grandes faces latérales, et en ce que ladite première face est une petite face latérale et ladite deuxième face est une grande face latérale dudit faisceau;
• ledit échangeur est configuré pour le refroidissement d'air de suralimentation d'un moteur d'un véhicule automobile, et
• le premier fluide est l'air de suralimentation et le second fluide de l'eau glycolée.

The exchanger may further comprise one or more characteristics following, taken separately or in combination:

• said first and second fluids flow countercurrently;
• said exchanger comprises a common header divided by said partition into two compartments so as to form on the one hand said inlet box and on the other hand said outlet box;
• the inlet manifold box and the outlet manifold of the first fluid are made by two separate parts;
• said bundle comprises a stack of tubes of which at least two tubes are joined, so that the lateral surfaces of said joined tubes lie substantially opposite the separation between said tubes, and that said partition separating said manifolds is situated substantially vis-à-vis the junction between said joined tubes;
• the intermediate manifold communicating with all of said first channels, is disposed on a third face of said beam opposite said first face, for the circulation "U" of the first fluid;
• said intermediate compartment communicating with all of said second channels, for the circulation "U" of the second fluid, is disposed on an end of said wall, opposite said pipes;
• said beam has a substantially parallelepipedal overall shape with two end faces, two small lateral faces and two large lateral faces, and in that said first face is a small lateral face and said second face is a large lateral face of said beam;
• said exchanger is configured for charge air cooling of an engine of a motor vehicle, and
• the first fluid is the supercharging air and the second fluid of the brine.

• la figure 1 représente une vue de côté d'un échangeur thermique,
• la figure 2 représente une vue éclatée de l'échangeur de la figure 1,
• la figure 3 est une vue en perspective éclatée d'un faisceau d'échange de l'échangeur de la figure 1,
• la figure 4 est une vue de côté du faisceau de la figure 3, et
• la figure 5 est une vue selon la coupe II de la figure 4.

Other features and advantages of the invention will emerge more clearly on reading the following description, given by way of illustrative and nonlimiting example, and the appended drawings among which:

• the figure 1 represents a side view of a heat exchanger,
• the figure 2 represents an exploded view of the exchanger of the figure 1 ,
• the figure 3 is an exploded perspective view of an exchange beam of the heat exchanger of the figure 1 ,
• the figure 4 is a side view of the beam of the figure 3 , and
• the figure 5 is a view according to section II of the figure 4 .

In these figures, the substantially identical elements bear the same references.

The invention relates to a heat exchanger 1, in particular for cooling the charge air for an engine, such as a diesel engine of a motor vehicle.

According to the embodiment described this exchanger is an exchanger called "air-water", that is to say an exchanger in which the fluids that exchange heat are air and water. In the case of a charge air cooler; the water is preferably water from the so-called "low temperature" cooling circuit of said engine; it is typically brine.

We have shown on the figure 1 such a heat exchanger 1. This exchanger 1 better visible on the exploded perspective view of the figure 2 , has a generally parallelepipedic general shape.

The exchanger 1 comprises a heat exchange bundle 3 between the first fluid such as air and the second fluid such as water.

For this purpose, the exchanger comprises a first inlet manifold 5 of the first fluid, in this case air, and a second air outlet manifold 7, to allow the circulation of air in the bundle 3; and an inlet pipe 9 of the second fluid, here water, and a water outlet pipe 11, to allow the circulation of water in the beam 3 by exchanging heat with the air.

As we see on the Figures 2 to 4 , the beam 3 has a generally parallelepipedal general shape. The beam 3 thus has two faces end 3a, 3b, two small side faces 3c, 3d and two large side faces 3e, 3f. Each large side face 3e, 3f is contiguous to a small side face 3c, 3d.

According to the illustrated embodiment, the inlet manifolds 5 and air outlet boxes 7 are attached to a small side face 3c, for example, of the bundle 3. These manifolds 5.7 are connected to pipes of a air circuit in which the exchanger 1 is mounted.

With reference to Figures 1 and 2 , the manifolds 5 and 7 are thus arranged one above the other being separated by a partition 13 visible on the figure 2 .

In order to seal the exchanger 1, the latter comprises a sealing means (not shown) between the manifolds and the bundle 3. Of course, the exchanger 1 also has a sealing means at the of the partition 13 for separating the manifolds 5.7. By way of example, it is possible to provide a seal.

The heat exchange bundle 3 comprises, for example, a stack of tubes 15, 15a, 15b, 15 ', 15 "( figure 3 ) parallel for the flow of air. This stack thus has two end tubes 15a, 15b in the stacking direction of the tubes 15; and these end tubes 15a, 15b delimit the end faces 3a, 3b of the bundle 3.

These tubes 15,15a, 15b, 15 ', 15' have for example respectively a generally flattened general shape.

The tubes 15, 15a, 15b, 15 ', 15' respectively define first air circulation channels which open into the inlet and outlet boxes 7 (cf. figures 2 and 3 ). The air is thus introduced into the tubes via the inlet box 5 and is collected at the outlet of the tubes by the outlet box 7.

Disturbing fins 17, for example of substantially corrugated shape, arranged in these tubes 15, 15a, 15b, 15 ', 15' can be provided to disturb the flow of air and to increase the exchange surface to facilitate heat exchange between air and water through the walls of the tubes 15,15a, 15b, 15 ', 15'.

The fins 17 may for example be brazed to the tubes 15,15a, 15b, 15 ', 15'.

More specifically, in known manner, these fins 17 can be made under the form of corrugated dividers, formed for example from a metal strip which is deformed to form the corrugations. Each corrugated spacer may be arranged to come into respective contact with the inner walls of a tube by the end regions of the corrugations (cf. figure 5 ).

The tubes 15, 15a, 15b also define between them second circulation channels for the flow of water.

The second channels are therefore interposed between the tubes 15,15a, 15b. And, the beam 3 has an alternating stack of first and second circulation channels.

For example, disruptors 19 of the water flow can be provided in these second channels. Such disrupters 19 are partially and schematically represented on the Figures 3 and 5 .

These disturbers 19 extend between two tubes, for example over the entire length between two adjacent tubes.

These disturbers 19 have a shape creating turbulence in the flow of water passing through them. For this purpose, the disrupters 19 may be made in the form of plates having disturbance patterns or, according to the example illustrated, be in the form of two superposed perforated disturbance plates 19.

Each plate 19 may be brazed to one of the two adjacent tubes defining a second channel.

These perturbation plates 19 form spacers between the tubes 15, 15a, 15b and make it possible to increase the exchange surface by disturbing the flow of water. This facilitates heat exchange between air and water through the walls of the tubes.

In this case, the beam 3 comprises an alternating stack of tubes and disrupters 19.

In addition, in this stack, at least two tubes 15 'and 15 "are joined which are not separated by a second channel or plate 19. According to the method of illustrated embodiment, two tubes 15 'and 15 "are joined.

These two joined tubes 15 ', 15 "are for example located substantially in the middle of the stack, as is better visible on the figure 5 these two joined tubes 15 ', 15 "delimit a first part A or first half of beam 3, and a second part or half B.

The first part A extends from an end tube 15a to a joint tube 15 '. The second part B extends from the second joint tube 15 "to the opposite end tube 15b.

According to the embodiment illustrated on the figures 2 and 5 , on the side of the small side face 3c of the beam 3, the ends of the tubes 15a, 15,15 'of the first part A open into the manifold 7 air outlet. The ends of the tubes 15 ", 15, 15b of the second part B open into the manifold 5. The junction between the tubes 15 'and 15" is found substantially vis-à-vis of the partition 13 between the two manifolds 5 and 7.

This arrangement allows a substantially "U" -circulation of the air in the tubes of the bundle 3.

In addition, the exchanger 1 comprises an intermediate collecting box 21 (cf. Figures 1 and 2 ) reported on the second small side face 3d opposite the first small side face 3c.

In order to seal the exchanger 1, the latter comprises a sealing means (not shown), such as a seal, between this intermediate collecting box 21 and the bundle 3.

The ends of the set of tubes 15,15a, 15b, 15 ', 15 "on the side of the second small side face 3d open into this intermediate collecting box 21 (cf. figures 2 and 3 ).

Thus, the air circulating in the tubes of the second part B is collected in this intermediate manifold 21 before circulating in the tubes of the first part A until it is discharged through the outlet box 7.

This intermediate manifold 21 opposed to the inlet manifolds 5 and output 7 therefore participates in the "U" circulation of the air in the beam 3.

In addition, the distribution boxes 5, 7 and 21 are formed together by collectors 23 ( figures 2 and 3 ) and complementary associated covers 25 and 27.

According to the illustrated embodiment, the two input and output boxes 7 are formed together with a collector 23 and an associated lid 25.

The lid 25 is formed in one piece and comprises the partition 13 dividing the lid 25 into two compartments, so as to form on the one hand the input box 5 and on the other hand the outlet box 7.

The manifold 23 is disposed at the end of the assembly of the tubes, at the level of the small lateral face 3c, and allows assembly with the associated cover 25.

The manifold 23 is formed in one piece and receives a plurality of tube ends from both the first portion A and the second portion B of the tube bundle.

To do this, the manifold 23 has a plurality of orifices 29 for receiving the ends of the tubes 15,15a, 15b and has a larger orifice 31 for receiving at the same time the ends of the two joined tubes 15 ', 15 ". For example, the larger orifice 31 has twice the dimensions of an orifice 29 of a single tube end.

Of course, the two manifolds 5 and 7 can also be made separately with two manifolds 23 and two associated lids.

Similarly, the intermediate box 21 is formed together with a collector 23 disposed at the end of the set of tubes, at the level of the small side face 3d and an associated cover 27.

The collector 23 is here identical to the collector 23 of the input and output boxes 5 and 7.

The cover 27 differs from the cover 25 in that it does not delimit two compartments separated by a partition 13. The cover 27 has a shape complementary to the shape of the collector 23 so as to define an air collection chamber in which open the ends of all the tubes.

Moreover, according to the embodiment illustrated on the Figures 1 to 4 , the heat exchanger 1 has two side walls 33 for closing the beam 3.

These walls 33 are for example reported on the two large opposite side faces 3, 3f of the beam 3 (FIG. figure 3 ). The walls 33 are therefore opposite the lateral surfaces of the stacked tubes of the bundle 3.

Fixing the walls 33 to the beam 3 may for example be done by soldering.

According to the example shown on the figure 2 the opposite side walls 33 are of generally rectangular shape so as to delimit together with the end tubes 15a, 15b an open parallelepiped shape to which are attached on the one hand the input and output boxes 7, and the other hand the intermediate box 21 for the distribution of air.

For this, the two walls 33 may respectively have fixing means 34 on the end tubes 15a, 15b.

As mentioned above, the inlet 9 and outlet 11 of the water pipes allow the circulation of water in the beam 3.

For this, these inlet pipes 9 and outlet 11 are formed on one of the walls 33. More specifically, to allow a flow "U" of water, the two pipes 9,11 are arranged at the level of a first end of a wall 33, being separated from one another.

The pipes 9, 11 are for example formed near the inlet boxes 5 and outlet 7 of the air.

As we notice on the figure 3 the wall 33 may have apertures 35, for example of substantially circular shape, for entry and exit, and at the right of this opening 35, a bulge 37 oriented towards the outside of the exchanger 1, as illustrated the figures 2 and 3 .

This bulge 37 is for example made by stamping.

The pipes 9 and 11 are respectively connected at the openings 35, and the wall 33 extending between the bulges 37 form a sealed separation between the inlet and outlet pipes 9 and 11 (cf. Figures 3 and 5 ).

In addition, this separation formed by the wall 33 extending between the two bulges 37 is located substantially vis-à-vis the side surfaces of the two joined tubes 15 'and 15 "(cf. figure 5 ).

This arrangement allows a substantially "U" circulation of the water.

Thus, the second fluid, here water, introduced into the beam 3 via the inlet pipe 9 circulates in the second channels interposed between the tubes 15a, 15,15 'of the first part A, and the water circulates in the second channels interposed between the tubes 15 ", 15, 15b before exiting via the outlet pipe 11.

In addition, an intermediate compartment 39 ( Figures 1 to 4 ) which communicates with the second channels of the first part A as well as with the second channels of the second part B of the bundle 3, so as to receive the water that has circulated in the first part A, then redistribute it to the second Part B for evacuation.

This intermediate compartment 39 therefore participates in the "U" circulation of the water in the bundle 3.

The intermediate compartment 39 is arranged on a face of the beam 3 perpendicular to the face 3d on which the intermediate manifold 21 is arranged.

This particular arrangement allows the double "U" circulation of the two fluids.

According to the illustrated embodiment, this intermediate compartment 39 is located on the same wall 33 as the inlet and outlet pipes 9 and 11, but at the opposite end.

In addition, so as to form a water collection chamber, this compartment 39 is for example in the form of a bulge of a wall 33, similarly to the bulges 37 to receive the inlet pipes 9 and output 11.

This bulge is for example made by stamping.

Claims (8)

1. Heat exchanger between a first fluid and a second fluid, said exchanger comprising:

   - a heat exchange core (3) for a heat exchange between the first and the second fluids, comprising first circulation channels of the first fluid and second circulation channels of the second fluid between said first channels,

   - an inlet collector box (5) for the first fluid and an outlet collector box (7) for the first fluid, into which the ends of said first channels open out, and

   - an inlet connection piece (9) for the second fluid and an outlet connection piece (11) for the second fluid,

   - said inlet (5) and outlet (7) collector boxes for the first fluid being fixed on a first side (3c) of said core (3) and being separated by a deflector (13) and said exchanger moreover comprising an intermediate collector box (21) communicating with said first channels to create a U-circulation of the first fluid in said first channels,

   - said exchanger comprising at least one wall (33) fixed on a second side (3e) of said core (3) adjacent to said first side (3c) and said inlet (9) and outlet (11) connection pieces for the second fluid being disposed at one end of said wall (33), being separated one from the other, and said exchanger comprising an intermediate compartment (39) communicating with said second channels for a U-circulation of the second fluid in said second channels,

   - said intermediate collector box (21) and said intermediate compartment (39) being disposed on sides (3d, 3e) of said core (3) perpendicular one to the other,

   characterized in that said core comprises a stack of tubes (15, 15a, 15b, 15', 15"), of which at least two tubes (15', 15") are joined in such a manner that:

   - the lateral surfaces of said joined tubes (15', 15") are located substantially opposite the junction between said connection pieces (9, 11), and that

   - said deflector (13) separating said collector boxes (5, 7) is located substantially opposite the junction between said joined tubes (15', 15").
2. Exchanger according to Claim 1, characterized in that it comprises a joint collector box divided by said deflector (13) into two compartments in such a manner as to form said inlet box (5), on the one hand, and said outlet box (7), on the other.
3. Exchanger according to Claim 1, characterized in that the inlet (5) collector box and the outlet (7) collector box of the first fluid are realized by two different parts.
4. Exchanger according to any one of the preceding claims, characterized in that the intermediate collector box (21) communicating with the assembly of said first channels is disposed on a third side (3d) of said core (3) opposite said first side (3c), for U-circulation of the first fluid.
5. Exchanger according to any one of the any one of the preceding claims, characterized in that the intermediate compartment (39) communicating with the assembly of said second channels, for the U-circulation of the second fluid, is disposed on an end of said wall (33), opposite said connection pieces (9, 11).
6. Exchanger according to any one of the preceding claims, characterized in that said core (3) exhibits a general form which is substantially parallelepiped with two end sides (3a, 3b), two small lateral sides (3c, 3d) and two large lateral sides (3e, 3f), and in which said first side (3c) is a small lateral side and said second side (3e) is a large lateral side of said core.
7. Exchanger according to any one of the preceding claims, characterized in that it is configured for the cooling of charge air of a motor vehicle engine.
8. Exchanger according to Claim 7, characterized in that the first fluid is charge air and the second fluid is glycol water.

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