EP3519756A1

EP3519756A1 - Collector box comprising a phase change material and heat exchanger comprising such a collector box

Info

Publication number: EP3519756A1
Application number: EP17787229.8A
Authority: EP
Inventors: Kamel Azzouz; Julien Tissot; Michael LISSNER; Patrick Boisselle; Ambroise SERVANTIE; Sébastien Garnier; Samuel BRY
Original assignee: Valeo Systemes Thermiques SAS
Current assignee: Valeo Systemes Thermiques SAS
Priority date: 2016-09-28
Filing date: 2017-09-28
Publication date: 2019-08-07
Also published as: WO2018060646A1

Abstract

The present invention relates to a collector box (1) for a heat exchanger, comprising a housing (11) having an external surface (12), and a phase change material (2) inside the housing (11). The present invention also relates to a heat exchanger comprising such a collector box (1).

Description

A collector box comprising a phase change material and heat exchanger comprising such a collector box.

The present invention relates to manifolds for heat exchangers. More specifically, this invention relates to heat exchangers used in motor vehicles, including charge air coolers and engine coolant coolers.

Usually, heat exchangers for motor vehicles comprise heat exchange channels in which circulates a heat transfer fluid. During its circulation in the heat exchange channels, the coolant exchanges heat with the medium surrounding the heat exchange channels. These heat exchanges are intended to heat or cool the heat transfer fluid. Two collector boxes respectively inlet and outlet are arranged on either side of the heat exchange channels so as to form a coolant circulation circuit extending from an inlet of the collector box of input to an outlet port of the outlet manifold box. The heat transfer fluid circulates in this circuit through the different heat exchange channels.

This type of heat exchanger is sized to withstand the temperatures reached during normal operation of the vehicle and dissipate enough heat in the temperature ranges defined by the car manufacturers. The most extreme temperatures are reached only briefly during certain operating stages of the exchanger. In the case of an engine coolant cooler, it has been estimated that for 90% of the operating time, only one-third of the radiator heat exchange area would be sufficient to dissipate enough heat to meet the conditions. engine operation. The radiator is therefore oversized because it is used to its full potential only occasionally in time.

In the case of a charge air cooler, frequent changes in inlet temperature require the selection of particularly resistant materials for the collector boxes. Such materials are relatively expensive. Better regulation of temperature variations would make it possible to use less expensive materials. The object of the invention is to remedy these drawbacks by providing a heat exchanger that is less sensitive to the extreme temperatures of the internal heat transfer fluid entering the exchanger or the medium surrounding the heat exchange channels.

For this purpose, the invention relates to a manifold for a heat exchanger comprising a housing having an outer surface, and a phase change material inside the housing.

The use of the collector box according to the invention makes it possible to improve the efficiency of the heat exchange occurring inside the collector box.

The manifold may further include heat exchange projections on the outer surface of the housing.

Thus, the projections increase the heat transfer between the housing and its external environment, for example the air entering under the hood of the vehicle in which the manifold is installed, allowing effective cooling of the housing. In fine, the coolant entering the manifold box will be in contact with a colder housing allowing a more efficient heat exchange between the coolant and the housing. Thus, within the collector box, there is no increase in the exchange surface between the coolant and the casing, but it is outside the collector box that the exchange surface between the carter and its environment is increased.

Furthermore, compared with a slip box without heat exchange projections but including a phase change material in its housing, the collector box of the present invention gives better results because it allows in particular the phase change material of to discharge, ie to cool, and so to regenerate.

The housing may be plastic or metal, and is preferably aluminum. The projections may be fins. In which case, the housing having a longitudinal axis, the fins may extend transversely to the longitudinal axis of the housing, preferably at 90 ° thereof.

Alternatively, the projections may be studs. In which case, the pads may be straight cylinders or cones. The straight cylinders can be chosen from those with a circular or rectangular base. With regard to the cones, these can be possibly truncated. Of course, a combination of two or more of these forms of pads can be used according to the needs of the manifold.

The distance between two projections is advantageously between 1 and 3 mm.

The thickness of the projections is advantageously between 0.5 and 1 mm.

The housing without the projections may be circumscribed in a parallelepiped of smaller volume, the projections are advantageously contained in the parallelepiped of smaller volume.

The height of the projections is advantageously less than 10 mm.

According to one embodiment, the collector box comprises:

- a casing having a longitudinal axis, a bottom, two lateral flanks extending from the bottom of the same side thereof to give a U-shaped cross-section, and a housing space between the two lateral flanks and the background ;

- phase change material in the housing housing space;

the phase change material is encapsulated in tubes.

The use of phase change material in the collector box allows dimensioning of the smaller heat exchanger. Moreover, the phase-change material makes it possible, during peak power (increase in temperature), to store this additional energy in order to restore it later outside these power peaks. This results in a more restricted temperature variation which is ideal for turbocharging air cooling. Also, thanks to the encapsulation of phase change material in tubes, the pressure drop problem is minimized. Moreover, the encapsulation of the phase change material in the tubes is easier than in balls. In addition, the tubes have the following advantage over beads: less encapsulation material is needed for the same volume of phase change material. The corollary is therefore that it is possible to increase the volume of material with phase change compared to ball encapsulation.

Other optional and non-limiting features are presented below.

The housing space may be divided into two portions in a plane substantially parallel to the mean plane of the bottom: a first portion closer to the bottom representing 2/3 of the volume of the housing space and a second portion further from the bottom representing 1/3 of the volume of the housing space; the phase change material being present only in the first portion.

The manifold may further comprise a tube holder having a base and two posts spaced from each other, the two posts having orifices, each orifices supporting one end of a tube. The base of this support can be perforated.

The housing may comprise means for fixing or retaining the tube support. These fixing or retaining means may be means for clipping the base to the housing.

The tube support advantageously extends in the direction of the longitudinal axis of the housing and the tubes are arranged in a general direction parallel to the longitudinal axis of the housing. In which case, each of the uprights may be a perforated plate whose normal to the plate is collinear with the longitudinal axis of the housing, the two uprights being located at the ends of the support, and the tubes may be upright tubes extending between the two amounts. Alternatively, each of the uprights may be a perforated plate whose normal to the plate is perpendicular to the longitudinal axis of the housing and does not intersect the bottom of the housing, the two uprights being located at the ends of the support, and the tubes may be corrugated tubes extending between the two uprights.

The housing may comprise a transverse plate sealing substantially in the middle of its longitudinal extension separating the housing space into two compartments: an inlet compartment and an outlet compartment;

the collector box can include two tube supports:

one disposed in the inlet compartment and the tubes of which are filled with a first phase-change material; and

- the other in the exit compartment and whose tubes are filled with a second phase change material;

the second phase change material may have a phase transition temperature of between 0.5 and 0.7 times that of the first phase change material.

Such a header box may be for a heat exchanger of a high temperature cooling radiator, wherein the first phase change material has a phase transition temperature of between 90 ° C and 110 ° C, and the second phase change material has a phase transition temperature of between 70 ° C and 90 ° C.

Alternatively, such a header box may be intended for a heat exchanger of a low temperature cooling radiator, in which the first phase change material has a phase transition temperature of between 60 ° C. and 70 ° C. and the second phase change material has a phase transition temperature of between 40 ° C and 50 ° C.

The tubes may be of polymer, preferably of polycarbonate. Alternatively, the tubes may be metal, preferably aluminum. The advantage of the metal over the polymer is greater rigidity for lower wall thickness so for the same occupied space there will be more phase change material in metal tubes than in polymer.

The present invention also relates to a heat exchanger comprising a collector box as described above, for example a high temperature radiator or a low temperature radiator.

The heat exchanger may in particular comprise heat exchange channels connecting an inlet manifold box and an outlet manifold, these channels and collector boxes being arranged to form a circuit in which circulates an internal heat transfer fluid from an orifice inlet manifold inlet to an exit orifice of the outlet manifold passing through the different heat exchange channels, and wherein generally tubular envelopes encapsulating a phase change material are housed in at least one of the collector boxes, the envelopes being substantially parallel to each other. Thus, when the temperature at the inlet of the internal coolant increases, or when the heat dissipated in the heat exchange channels is smaller, for example because the medium surrounding the heat exchange channels has a higher temperature, the envelopes encapsulating the phase change material temporarily absorbs the excess heat of the internal heat transfer fluid passing through the heat exchanger thereby attenuating the temperature peaks of the internal heat transfer fluid.

According to other optional features corresponding to different embodiments of the heat exchanger according to the invention:

the phase change material has a latent heat of fusion greater than 280 kJ / m 3;

the phase-change material passes from the solid phase to the liquid phase at a temperature in a melting point range of between 20 and 110 ° C., and more particularly chosen:

• between 45 and 55 ° C if the heat exchanger is intended for the cooling of the engine charge air,

• between 50 and 100 ° C if the heat exchanger is intended for the cooling of a gearbox,

- between 80 and 110 ° C if the heat exchanger is intended for engine cooling;

the phase-change material is chosen from a fatty acid, a fatty alcohol, a paraffin and a hydrated salt;

the envelopes have a circular section whose external diameter is between 1 and 8 mm;

the internal heat transfer fluid is in gaseous form;

the internal heat transfer fluid is in liquid form;

the heat exchanger comprises envelopes positioned transversely relative to one another using means chosen from:

at least one spacer ring carried by an envelope,

a transverse plate provided with positioning pegs fitted into envelope end holes,

- a spacer grid traversed by envelopes, positioning transversely envelopes crossed between them;

the heat exchange channels are tubes with a substantially circular or oblong section;

an external heat transfer fluid, liquid or gaseous, circulates outside the channels heat exchange, so as to exchange heat with the heat exchange channels essentially by convection,

fins are formed on an outer surface of the at least one of the collector boxes housing the envelopes,

the fins are shaped on at least one portion of outer surface located in correspondence of said at least one manifold.

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

FIG. 1 is an exploded perspective view of an engine coolant cooling radiator, according to a first embodiment of the invention,

FIG. 2 is a perspective view of a detail of the cooling radiator shown in FIG. 1;

FIG. 3 is a perspective view of a detail of the cooling radiator shown in FIG. 1 with tearing of a collecting box of this exchanger,

FIG. 4 is an exploded perspective view of a detail of the cooling radiator shown in FIG. 1 showing in more detail a transverse plate provided with positioning pins;

FIG. 5 is a view similar to that of FIG. 3 showing spacer rings,

FIG. 6 is a perspective view of an envelope encapsulating phase change material on which a spacer ring is placed,

FIG. 7 is a sectional view of a plurality of envelopes of phase change material positioned relative to one another by a spacer grid,

FIG. 8 is a perspective view of a charge air cooler according to a second embodiment of the invention, in which a collector box is shown in section,

FIG. 9 is a perspective view of an envelope encapsulating phase change material used in the cooler shown in FIG. 8, FIG. 10 is a perspective view of a detail of a heat exchanger comprising a slip box according to the present invention; Figure 11 is a perspective view of a detail of a heat exchanger comprising a water box whose housing has been partially removed to give a glimpse of the phase change material;

Figure 12 is a perspective view of an embodiment of a finned manifold according to the present invention;

Figure 13 is an enlargement of Figure 12; and

Figure 14 is a perspective view of an embodiment of a slip box with pads according to the present invention.

FIG. 15 is a three-quarter view of an example assembly of straight tubes for encapsulating phase-change material on a support as provided by the present invention;

Figure 16 is a three-quarter view taken at another corner of the same assembly of Figure 15 showing the base of the support;

Fig. 17 is a diagram showing the arrangement of two assemblies of Fig. 15 in a header box with an inlet compartment and a heat transfer fluid outlet compartment;

Figure 18 is a partial view from below of the manifold of Figure 17 showing the base of the support is the fastening means or retainer; Fig. 19 is a three-quarter view of an exemplary corrugated tube assembly for encapsulating phase change material on a carrier as provided by the present invention;

Figure 20 is the same type of view as Figure 4 but with the assembly of Figure 19; and

FIG. 21 schematically represents a corrugated tube having rectilinear sections and toric sections. Figures 1 to 7 show a heat exchanger 10 according to a first embodiment of the invention forming for example a coolant cooling radiator of a motor vehicle engine.

This radiator 10 comprises a multitude of heat exchange channels 12 parallel to each other. These heat exchange channels 12 have a tubular shape whose section may be oblong, circular or other. The heat exchange channels 12 are delimited by walls 13. Each channel 12 is fixed at each of its ends to a holding member 14 which may also be called collector plate or collector, which positions the channels 12 relative to each other. other. During the operation of the radiator 10, an internal heat transfer fluid 16 circulates inside the exchange channels This fluid 16 is a cooling liquid, for example, glycol water. Outside the heat exchange channels 12, an external heat transfer fluid 18 circulates through the radiator 10. This fluid 18 is air. When it circulates in the heat exchange channels 12, the internal heat transfer fluid 16 transmits heat to the walls 13 of the channels 12. Thus, the internal heat transfer fluid 16 cools and its outlet temperature of the channels 12 is lower than The heat transmitted to the walls 13 of the heat exchange channels 12 diffuses by conduction, in particular to cooling fins 20 housed between the heat exchange channels 12. These fins 20 transfer their heat, essentially by convection, to the external coolant 18.

The cooling fins 20 are corrugated sheets of thermally conductive material which are attached to the walls 13 of the heat exchange channels 12.

An inlet collecting box 22 and an outlet collecting box 24 are arranged on either side of the heat exchange channels 12. These collecting boxes 22, 24 have a generally elongated shape and are fixed in a manner known per se to holding members 14. Thus, the different heat exchange channels 12 connect the inlet manifold box 22 to the outlet manifold 24.

The manifolds 22, 24 are members whose function is to divide the flow of internal heat transfer fluid 16 entering the radiator 10 and to fuse the flows of internal heat transfer fluid 16 leaving the heat exchange channels 12. The collector box of 22 and the outlet manifold 24 are respectively provided with an inlet port 26 and an outlet port 28. The manifolds 22, 24 are also each provided with a connection face 30 attached to the corresponding holding member 14 and connecting the manifolds 22, 24 to the channels 12.

Thus, as it circulates through the radiator 10, the internal heat transfer fluid 16 circulates in a circuit going from the inlet orifice 26 of the inlet manifold 22 to the outlet orifice 28 of the box outlet manifold 24 passing through the different collecting boxes 22, 24 and the heat exchange channels 12.

In the manifolds 22, 24, envelopes 32 encapsulating a material to phase change 34 are accommodated. A phase change material 34 is a material whose latent heat is important and which is used in a temperature range including its phase change temperature. In this way, a phase change material is capable of storing or returning a large amount of heat during its phase change. The phase change material used is selected from a fatty acid, a fatty alcohol, a paraffin and a hydrated salt.

The phase change material 34 used in this radiator 10 has a latent heat of fusion greater than 280 kJ / m 3. The phase change material 34 used has a melting temperature in a range selected from 20 to 110 ° C, and more particularly from 50 ° C to 100 ° C, 45 ° C to 55 ° C and 80 ° C to 110 ° C. ° C according to the expected temperature of the internal coolant 16 at the location where it is positioned in the radiator 10. Ideally, the melting temperature of the phase change material 34 should be slightly greater than the temperature of the internal heat transfer fluid 16 in contact with the envelopes 32 encapsulating this phase change material 34 when there is no overheating.

The envelopes 32 have a generally tubular shape, of outer section between 1 and 8 mm. Each envelope 32 is closed at these two ends by a plug 36.

The various envelopes 32 are of substantially the same length and are positioned substantially parallel to each other so as to form a beam 38. Each bundle 38 of envelopes 32 is housed in the corresponding manifold 22, 24, substantially parallel to the longitudinal direction of the manifold 22, 24.

Advantageously, fins are formed on an outer surface of one of the collector boxes, or two collector boxes, housing the envelopes 32. These fins increase the heat transfer between the water box and its external environment, for example with the air entering under the hood of the vehicle in which the manifold is installed, allowing effective cooling of the air box. The vanes make it possible to improve the efficiency of the heat exchange occurring inside the header box and consequently allow the phase change material to discharge, ie to cool, and thus to regenerate. The fins may in particular be shaped on an outer surface portion of the collector box located near the envelopes housed in the collector box. Preferably, the portion is located on the collector box corresponding to the location of the envelopes 32 in said at least one collector box, as illustrated in FIG. 1 with the fins present on outer surface portions of the boxes 22 and 24. , the fins make it possible to improve the heat exchange in an area of the collector boxes where the envelopes are located, which further improves the efficiency of the heat exchanger with a better absorption of the temperature peaks and a better regeneration of the material to phase change through faster cooling obtained by the presence of fins on a suitable area of the box.

The radiator 10 comprises transverse positioning means 40, 42, 46 of the envelopes 32 relative to each other. These positioning means 40, 42, 46 may comprise:

spacer rings 40 (see FIGS. 5 and 6) carried by the envelopes

32

transverse plates 42 (see FIGS. 1, 3 and 4) nested in orifices

44 formed in the end of the envelopes 32,

spacer grids 46 (see FIG. 7) traversed by a portion of the envelopes 32, positioning the envelopes 32 between them transversely.

The spacer rings 40 are tubular elements placed on the envelopes 32. The thickness of these rings 40 keeps the envelopes 32 away from each other.

The transverse plates 42 are plates housed at the ends of bundles 38 of envelopes 32. These plates 42 are provided with locating pins 48 which are fitted into the orifices 44 formed at the ends of the envelopes 32 of phase-change material 34 The positioning pegs 48 position the envelopes 32 axially and transversely between them.

Figures 7 to 9 show a heat exchanger according to a second embodiment. In this embodiment, elements similar to the first embodiment are designated by identical references.

In this embodiment, the heat exchanger is an air cooler of supercharge 50. The first heat transfer fluid 16 passing through this cooler is a pressurized gas from a turbocharger and intended to supply a heat engine. It can be seen in FIG. 8 that the shape of the envelopes 32 of phase change materials 34 can be adapted to the use that is made of them. In particular, in this embodiment, the envelopes 32 have a greater diameter than in the first embodiment. In this way each envelope 32 contains a larger amount of phase change material 34.

The invention is not limited to the embodiments presented and other embodiments will become clear to those skilled in the art. It is possible in particular that the second heat transfer fluid 18 is a liquid.

Referring now to Figures 10 to 13. The manifold 1 comprises a housing 11 (see Figure 12). The housing is made of plastic or metal and has an outer surface 120. The housing typically has a longitudinal axis A and a cross section relative to the longitudinal axis A in a U-shape, that is to say with an opening on a face. In Figures 12 and 13, the open face is opposite to the visible face. This opening allows the connection to the exchange beam of the heat exchanger. The interior volume of the U is intended to receive a coolant during operation of the heat exchanger and possibly other components such as a phase change material. Thus, the housing 11 has a neck shape whose ends are closed. Furthermore, as can be seen in FIGS. 12 and 13, the "bottom" of the neck, ie the curved part of the U, does not have a homogeneous shape along the longitudinal axis A of the casing 11. The casing 11 is preferably in plastic (for example based on PA polyamide loaded with fiberglass), or aluminum.

The manifold 1 also includes heat exchange projections 130, 140 on the outer surface 120 of the housing 11. The projections 130, 140 provide the manifold box 1 additional heat exchange surfaces to cool the housing 11 during operation of the heat exchanger, the housing 11 in turn for cooling the heat transfer fluid. The projections 130, 140 are preferably integral with the housing, and can be made of plastic or metal (preferably aluminum).

Advantageously, the casing 11 without the projections is circumscribed in a parallelepiped of smaller volume P, the projections 130, 140 are contained in the parallelepiped of smaller volume P. The parallelepiped of smaller volume P is the smallest parallelepiped in volume which can contain the housing 11 of the manifold without taking into account the projections, the possible ports for connection of pipe is also not taken into account. Thus, the size of the manifold 1 and ultimately the heat exchanger is not increased.

In a first embodiment, the projections are fins 130 (see FIG.

12). The fins 130 as heat exchange projections also make it possible to mechanically reinforce the manifold 1, in particular in the face of cyclic pressure constraints. The fins 130 may extend transversely to the longitudinal axis A of the housing 11, preferably at 90 ° relative thereto. The fins 130 are advantageously parallel to each other allowing the disposition of a large number of fins on the outer surface 120 of the casing 11.

In another embodiment, the projections may be studs 140 (see FIG.

13). The use of pads 140 with respect to the fins 130 has the advantage of increasing turbulence in the air around the manifold 1 during operation thereof, which therefore increases the heat transfer between the manifold 1 and the surrounding air. These pads 140 may be straight cylinders, preferably circular 140a or rectangular base 140b (including square). The pads 140 may still be cones 140c, possibly truncated. A combination of two or more types of pads 140 may be used according to the needs of the manifold 1. Preferably, the studs 140 are distributed homogeneously on the outer surface 120 of the casing 11. For example, the pads 140 are distributed on the outer surface 120 of the housing 11 in a square mesh, preferably so that one side of the square mesh is parallel to the longitudinal axis A of the housing 11.

The distance d between two projections 130, 140 (see Figure 14) is preferably between 1 mm and 3 mm to limit the pressure drop of the air. The distance d is understood as the distance measured perpendicularly, possibly perpendicularly to the tangent, to the faces of the projections 130, 140 at the point in question.

When the distance d is constant along the casing 11, it is called p step. This pitch p is preferably between 1 mm and 3 mm. At identical pitch p, there is the same increase in heat transfer for the fins 130 and the studs 140 distributed in square mesh.

The thickness e of the projections 130, 140 is preferably constant and between 0.07 mm and 1 mm, preferably between 0.5 mm and 1 mm, more preferably between 0.7 mm and 1 mm. The last two intervals make it possible in particular to prevent the projections 130, 140 from bending at the slightest touch. The thickness e is understood as the smallest dimension of the projection 130, 140. For example, for a fin 130, the thickness e is the distance between the two faces opposite of the fin 130; for a right circular cylindrical stud 140a, the thickness e is the diameter of the circular base; for a rectangular cylindrical stud with a rectangular base 140b, respectively square, the thickness e is the width of the rectangular base, respectively the side of the square base. For the purposes of definition of the present invention, for a conical lug 140c or frustoconical (truncated cone), the thickness e is the diameter of the circular base of the cone.

The height h of the projections is preferably less than 10 mm. The height h is understood as the distance measured at a point of the base of the projection 130, 140 perpendicular to the outer surface 120 of the housing 11 and the peak of the projection. Preferably, the height h in each of the points of the projections 130, 140 is chosen so that the projections 130, 140 occupy the remaining height between the outer surface 120 of the casing 11 and the parallelepiped of smaller volume P.

As illustrated in FIG. 11, the collector box 1 may advantageously also comprise a phase-change material 2 disposed in the space inside the casing 11, that is to say in the volume of the U. The Phase change material 2 is typically provided in a sheath to contain it in the header box 1.

The manifold box 1 may also include a heat transfer fluid inlet port 15, an outlet port 160 for heat transfer fluid and / or a degassing / expansion port 17 for the heat transfer fluid for the connection of the manifold to a pipe respectively. delivery of heat transfer fluid, to a coolant discharge pipe, to a coolant / gas coolant expansion pipe. The input port 15 is generally provided at one end of the housing 11 while the output port 160 may be provided at any point between the two ends of the housing 11. When the degassing / expansion port 17 is provided, the latter is preferably disposed at the end of the housing 11 opposite that at which the input port 15 is located.

This manifold 1 can be used in a heat exchanger 10 and can be either a water box or an air box. Such a heat exchanger 10 typically comprises an exchange beam 3 provided with a superposition of plates or tubes and generally having a parallelepipedal shape, a beam casing 4 generally closed on four sides and open on two opposite faces, the box the collector 1 being disposed against one of the open sides so that a heat transfer fluid can pass from the exchange beam 3 to the manifold 1 and / or the manifold 1 to the exchange bundle 3.

Such a heat exchanger 10 may be a high or low temperature cooling radiator, a cabin heater, a condenser, an air / air or air / water charge air cooler. Reference is now made to the embodiments of FIGS. 15 to 21. The collector box 1 here comprises a housing 11 having a longitudinal axis A, a bottom 21 and two lateral flanks 220, 230 extending from the bottom 21 of the same side thereof to give a U-shaped cross section. The space between the two sides 220, 230 and the bottom 21 forms a housing space to receive in particular the coolant during operation of the heat exchanger. The bottom 21 and the two lateral flanks 220, 230 extending in the direction of the longitudinal axis A of the casing 11. The casing 11 also typically comprises two end flanks extending one of the lateral flanks 220, 230 towards the other 230, 220 so as to close the casing 11 at its ends. The opposite side to the bottom 21 has an opening which is in particular to be coupled to a heat exchange casing.

The manifold box 1 also comprises phase change material 300 in the housing housing space 11. This phase change material 300 is encapsulated in tubes 310, 320. Typically each of these tubes 310, 320 has a circular cross section, the outside diameter is preferably between 1 and 8 mm. They are sealed at their two ends 311, 321, for example by the same material in which they are made, by rivets 312 or by crimping (as explained below). The extension of the tubes 310, 320 may be rectilinear (FIGS. 15 to 18) or corrugated (FIGS. 19 to 21). By corrugated, it is understood in the context of this presentation any rounded shape ranging from zigzag to slot, for example sinusoidal or having rectilinear sections 323 interconnected by toric sections 324, preferably drawing a half arcuate circle; it is this latter form which is shown in Figures 19 to 21. The smallest distance separating the walls of two tubes 310, 320 is preferably between 0.5 and 2 mm.

In general, the phase change material 300 may comprise paraffin and / or vegetable oils.

The tubes 310, 320 may be made of polymer, for example polycarbonate, polyester or polyamide; especially when their extension is rectilinear, possibly loaded. In this case, the tubes 310, 320 have a wall with a thickness of between 0.05 and 0.4 mm. The tubes 310, 320 may also be made of metal, preferably aluminum, to have tubes of less thickness than plastic tubes because aluminum is more thermally conductive and stronger than plastic. In this case, the tubes 310, 320 have a wall thickness between 0.05 and 0.5 mm, preferably below 0.2 mm. The advantage of the metal is that it allows a greater heat transfer between the coolant and the phase change material 300 than a polymer. Moreover, the mechanical strength of the metal is greater than that of the polymers, making it possible to provide tubes 310, 320 having a wall of smaller thickness, typically between ... and ... mm. Therefore, for the same external volume of tube, a greater amount of phase change material 300 can be placed in each tube 310, 320. Furthermore, the metal is particularly suitable for corrugated tubes 320 because it provides a better mechanical strength preventing the deformation of the corrugated tubes by the pressure exerted by the coolant, the weight of the tubes 320, or because of the high temperatures that can prevail in the manifold 1.

The accommodation space can be divided into two portions 240, 250 in a plane substantially parallel to the mean plane of the bottom 21 of the housing 11: a first portion 240 closer to the bottom 21 and a second portion 250 further from the bottom 21 of the housing ; the phase change material 300 being present only in the first portion 240. The first portion 240 preferably represents a larger volume of the housing space than the second portion 250, in particular between 55 and 75% of the volume of the space housing, preferably between 60 and 70% of the volume of the housing space, preferably 2/3, the second portion 250 occupying the rest of the volume of the housing space.

In order to maintain the tubes 310, 320 in the manifold box and in particular in the first portion 240 of the housing space, the manifold 1 may further comprise a tube support 400 having a base 410 and two spacers 420 remote the one of the other, the two uprights 420 having orifices 421, each orifices 421 supporting one end 311, 321 of a tube 310, 320, in particular by one of the rivets 312, 322 serving to plug the tube, or by crimping of each end 311, 321 of the tube 310, 320 on the surface surrounding an orifice 421 of the upright 420. The uprights 420 allow the centering of the tubes 310, 320 in the manifold 1. The tube support 400 is preferably made of polymer, always preferably polyamide, more preferably polyamide 6.6. The base 410 and the two uprights 420 may have come from molding.

The base 410 is advantageously perforated, for example having the form of a grid with orifices 411 preferably oblong always extending preferentially in the same direction as the longitudinal axis A of the housing. This grid makes it possible to retain the tubes 310, 320 if ever one of them is detached from the orifices 421 of the uprights 420.

Furthermore, the casing 11 may comprise means for fixing or retaining 280 of the tube support 400, in particular by coupling to the base 410. In one embodiment, the attachment or retaining means 280 are clipping means of FIG. the base 410 of the tube support 400 to the housing 11. For example, each of the clipping means is a shim whose section is a right-angled triangle whose one side other than the hypotenuse is fixed against an inner wall of the housing, the wall being able to be that of a transverse sealed plate (described in FIG. further), the other side other than the hypotenuse is turned towards the bottom so that the hypotenuse is turned towards the opening of the housing. The other side other than the hypotenuse acts as a stop retaining the support, and in particular by contact with the base, in the first portion of the housing space. In one embodiment, two clipping means 280 are used to fix or retain a tube support 400, for example on two of its opposite sides, in particular the two opposite sides along an axis parallel to the extension of the support. The clipping means 280 are preferably integrally formed with the casing 11, in particular with the end flanks of the casing and / or with the transverse plate 200.

The tube support 400 may extend in the direction of the longitudinal axis A of the casing 11 and the tubes 310, 320 are arranged in a general direction parallel to the longitudinal axis A of the casing 11. In this case, each of the uprights 420 may be a perforated plate whose normal to the plate is collinear with the longitudinal axis of the housing, the two uprights 420 being located at the ends of the support 400, and the tubes 310 are preferably straight tubes extending between the two uprights 420, preferably in a direction parallel to the longitudinal axis A of the housing 1 1. In this variant, the orifices 421 present on the perforated plate are preferably distributed in a square, triangular or hexagonal mesh. In another variant, each of the uprights 420 may be a perforated plate whose normal to the plate is perpendicular to the longitudinal axis A of the housing 1 1 and does not intersect the bottom 21 of the housing 11, the two uprights 420 being located at the ends of the support 400, and the tubes 320 are preferably corrugated tubes extending between the two uprights 420. In this variant, each corrugated tube 320 preferably waves between two parallel virtual lines 51, 52 extending in the same direction the longitudinal axis A of the casing 11 and separated by a distance close to that separating the two lateral flanks 220, 230 of the casing 11, for example between 80 and 99% of that distance. Still in this variant, the corrugated tubes 320 are arranged in layers with a single tube 320 per layer and each of the openwork uprights 420 has a row of orifices 421 superimposed on each other in a direction substantially perpendicular to the longitudinal axis A of the casing 11 and not intersecting any lateral flanks 220, 230 of the casing 11.

The accommodation space can be divided into two compartments 260, 270, in particular a heat transfer fluid inlet compartment 260 and an outlet compartment 270. of heat transfer fluid. For this, the housing 11 may comprise a transverse plate 200 substantially sealed in the middle of its longitudinal extension. The transverse plate 200 can be integral with the casing 11 including the two lateral flanks 220, 230 thereof. The collector box 1 can then comprise two tube supports 400:

one disposed in the inlet compartment 260 and the tubes 310, 320 of which are filled with a first phase-change material; and

the other in the outlet compartment 270 and the tubes 310, 320 of which are filled with a second phase-change material.

The first and second phase change materials may be the same. However, it is sometimes more advantageous for them to be different, especially so that the second phase-change material has a phase transition temperature of between 0.5 and 0.7 times that of the first phase-change material. . For example, the first phase change material has a phase transition temperature of between 90 ° C and 110 ° C, and the second phase change material has a phase transition temperature of between 70 ° C and 90 °. vs. This variant is particularly advantageous when the header is intended for a heat exchanger of a radiator with high temperature cooling. As another example, the first phase change material has a phase transition temperature of between 60 ° C and 70 ° C, and the second phase change material has a phase transition temperature of between 40 ° C and 50 ° C. vs. This variant is particularly advantageous when the header is intended for a heat exchanger of a radiator with low temperature cooling.

The manifold 1 may also include a heat transfer fluid inlet port 291, especially if the manifold 1 is an inlet manifold, or an outlet port 292 of heat transfer fluid, especially if the water can 1 is a box outlet collector (circulation of heat transfer fluid in I). In the case where the manifold 1 is an inlet and outlet manifold (circulation of the heat transfer fluid U), it may include an inlet port 291 opening into the inlet compartment 260, and a port 292, 292 has an opening opening preferentially both in the first portion 240 and both in the second portion 250 of the space of housing. Preferably, the entire area of the opening opens into the first portion 240. The input port 291 is preferably integral with the housing, including one of the side flanks 220, 230 thereof. Likewise, the output port 292 is preferably integral with the housing, in particular one of the lateral flanks 220, 230 thereof. When both types of port are provided, they are preferably placed on the same side of the housing 11.

In general, the casing 11 having an inlet port 291 and the arrangement of the phase-change material are made in such a way that, in operation, the heat-transfer fluid first comes into contact with the encapsulating tubes. the heat-change material through the input port 291 before exiting the open housing side to the exchange beam to which the manifold 1 is coupled.

Such a manifold 1 can be used in a heat exchanger, for example a high temperature radiator or a low temperature radiator, especially such mechanical or brazed radiators. Such a heat exchanger further comprises an exchange beam comprising a stack of tubes and a beam housing housing the exchange beam. The beam housing being attached to the manifold 1. Phase change material may also be provided in the tubes of the exchange bundle, especially for mechanical radiators.

Claims

1. A collector box (1) for a heat exchanger (10) comprising:

a housing (11) having an outer surface (120);

a phase change material (2) inside the housing (11).

A header (1) according to claim 1, including heat exchange projections (130, 140) on the outer surface (120) of the housing (11).

3. collector box (1) according to claim 1 or claim 2, wherein the housing (11) is plastic.

4. collector box (1) according to claim 1 or claim 2, wherein the housing (11) is aluminum.

5. collector box (1) according to one of the preceding claims, wherein the projections (130, 140) are fins (130).

6. collector box (1) according to claim 5, wherein the housing (11) having a longitudinal axis (A), the fins (00) extend transversely to the longitudinal axis (A) of the housing (11), preferably at 90 ° with respect thereto.

7. collector box (1) according to one of claims 1 to 4, wherein the projections (130, 140) are pads (140).

8. collector box (1) according to claim 5, wherein the studs (140) are straight cylinders, preferably circular base (140a) or rectangular (140b), or cones (140c), optionally truncated.

9. collector box (1) according to one of the preceding claims, wherein the distance (d) between two projections (130, 140) is between 1 and 3 mm.

10. collector box (1) according to one of the preceding claims, wherein the thickness (e) of the projections (130, 140) is between 0.07 mm and 1 mm.

11. collector box (1) according to one of the preceding claims, wherein the housing (11) without the projections being circumscribed in a parallelepiped of weaker volume (P), the projections (130, 140) are contained in the parallelepiped of smaller volume (P).

12. collector box (1) according to one of the preceding claims, wherein the height (h) of the projections (130, 140) is less than 10 mm.

The header (1) according to claim 1, wherein:

- the housing (11) has a longitudinal axis (A) and has a bottom (21), two side flanks (220, 230) extending from the bottom (21) of the same side thereof to give a U-shaped cross-section, and a housing space between the two lateral flanks (220, 230) and the bottom (21);

- Phase change material (300) in the housing housing space (11), the phase change material (300) being encapsulated in tubes (310, 320).

14. collector box (1) according to the preceding claim, wherein the housing space is divided into two portions (240, 250) in a plane substantially parallel to the mean plane of the bottom (21): a first portion (240) plus near the bottom (21) representing 55 to 75%, preferably 2/3, the volume of the housing space and a second portion (250) further from the bottom representing the rest of the volume of the housing space; the phase change material being present only in the first portion.

A header (1) according to claim 13 or claim 14, further comprising a tube holder (400) having a base (410) and two posts (420) spaced apart from one another, the two posts (420) having orifices (421), each port (421) supporting one end (311, 321) of a tube (310, 320).

16. collector box (1) according to the preceding claim, wherein the base (410) is perforated.

17. A water box (1) according to claim 15 or claim 16, wherein the housing (11) comprises means for fixing or retaining (280) of the tube support (400).

18. collector box (1) according to the preceding claim, wherein the fastening means or retaining means (280) are means for clipping the base (410) of the support of tubes (400) to the housing (11).

Picking box (1) according to one of claims 15 to 18, in which the tube support (400) extends in the direction of the longitudinal axis (A) of the housing (11) and the tubes ( 310, 320) are arranged in a general direction parallel to the longitudinal axis (A) of the housing.

20. Collector box (1) according to the preceding claim, wherein each of the uprights (420) is a perforated plate whose normal to the plate is collinear with the longitudinal axis (A) of the housing (11), the two uprights ( 420) being located at the ends of the support (400), and the tubes (310) are straight tubes extending between the two uprights (420).

21. A header (1) according to claim 19, wherein each of the uprights (420) is a perforated plate whose normal to the plate is perpendicular to the longitudinal axis (A) of the housing (11) and does not intersect the bottom (21) of the housing (11), the two uprights (420) being located at the ends of the support (400), and the tubes (320) are corrugated tubes extending between the two uprights (420).

22. collector box (1) according to one of claims 15 to 21, wherein the housing (11) comprises a transverse plate (200) substantially sealed in the middle of its longitudinal extension separating the housing space into two compartments (260 , 270): an input compartment (260) and an output compartment (270);

the collector box (1) comprising two tube supports (400):

one disposed in the inlet compartment (260) and the tubes (310, 320) of which are filled with a first phase change material; and

the other in the outlet compartment (270) and the tubes (310, 320) of which are filled with a second phase-change material;

the second phase change material has a phase transition temperature of between 0.5 and 0.7 times that of the first phase change material.

A header box (1) according to claim 22 for a heat exchanger of a high temperature cooling radiator, wherein the first phase change material has a phase transition temperature of between 90 ° C and 100 ° C. 1 10 ° C, and the second phase change material has a phase transition temperature of between 70 ° C and 90 ° C.

A header (1) according to claim 22 for a heat exchanger of a low temperature cooling radiator, wherein the first phase change material has a phase transition temperature of between 60 ° C and 60 ° C. 70 ° C, and the second phase change material has a phase transition temperature of between 40 ° C and 50 ° C.

25. collector box (1) according to one of claims 13 to 24, wherein the tubes (310, 320) are made of polymer, preferably polycarbonate.

26. collector box (1) according to one of claims 13 to 24, wherein the tubes (310, 320) are metal, preferably aluminum.

27. Heat exchanger (10, 50) comprising heat exchange channels (12) connecting an inlet manifold (22) and an outlet manifold (24), said manifolds (12) and manifolds (22, 24) being arranged to form a circuit in which an internal heat transfer fluid (16) circulates from an inlet (26) of the inlet manifold (22) to an outlet port (28) of the box outlet manifold (28) passing through the different heat exchange channels (12), characterized in that at least one of the inlet and outlet manifolds is a manifold according to any one of the preceding claims .

28. Heat exchanger (10, 50) according to the preceding claim, wherein the phase change material (34) has a latent heat of fusion greater than 280 kJ / m3.

The heat exchanger (10, 50) according to any one of claims 27 and 28, wherein the phase change material (34) passes from the solid phase to the liquid phase at a temperature within a range of and 110 ° C.

30. Heat exchanger according to the preceding claim, wherein, for the cooling of a vehicle gearbox, the temperature range at which the phase change material (34) passes from the solid phase to the liquid phase is chosen. between 50 and 100 ° C.

31. Heat exchanger according to Claim 29, in which, for the cooling of a box of the charge air of an engine, the range of The temperature at which the phase change material (34) passes from the solid phase to the liquid phase is selected from 45 to 55 ° C.

32. Heat exchanger according to claim 29, wherein, for the cooling of a vehicle engine, the temperature range at which the phase change material (34) passes from the solid phase to the liquid phase is selected from 80 and 110 ° C.

33. Heat exchanger (10, 50) according to any one of claims 27 to

32, wherein the phase change material (34) is selected from a fatty acid, a fatty alcohol, a paraffin and a hydrated salt.

34. Heat exchanger (10, 50) according to any one of claims 27 to

33, wherein the envelopes (32) have a circular section whose outer diameter is between 1 and 8 mm.

35. Heat exchanger (10, 50) according to any one of claims 27 to

34, wherein the internal heat transfer fluid (16) is in gaseous form.

36. Heat exchanger (10, 50) according to any one of claims 27 to 34, wherein the internal heat transfer fluid (16) is in liquid form.

37. Heat exchanger (10, 50) according to any one of the preceding claims, comprising envelopes (32) positioned transversely relative to one another by means of at least one spacer ring (40) carried by an envelope (32).

38. A heat exchanger (10, 50) according to any one of claims 27 to 37, comprising envelopes (32) positioned transversely relative to one another by means of a transverse plate (42) provided with pins ( 48) nested in end ports (44) of envelopes (32).

39. Heat exchanger (10, 50) according to any one of claims 27 to 37, comprising envelopes (32) positioned transversely relative to each other using a spacer grid (46) traversed by envelopes (32), transversely positioning the envelopes (32) traversed between them.

40. A heat exchanger (10, 50) according to any one of claims 27 to

39, wherein the heat exchange channels (12) are substantially circular or oblong section tubes.

41. Heat exchanger (10, 50) according to one of Claims 27 to

40, in which an external heat transfer fluid (18), liquid or gaseous, circulates outside the heat exchange channels (12), so as to exchange heat with the heat exchange channels (12) essentially by convection.

42. Heat exchanger (10, 50) according to any one of claims 27 to

41, wherein fins are formed on an outer surface of the at least one of the manifolds housing the envelopes (32).

43. Heat exchanger (10, 50) according to the preceding claim, wherein the fins are formed on at least one outer surface portion located in correspondence of the envelopes (32) in said at least one manifold.

44. Heat exchanger according to any one of claims 27 to 43, wherein the latter is a high temperature radiator or a low temperature radiator.