EP3548828B1 - Device for distributing a refrigerant inside tubes of a heat exchanger constituting a refrigerant circuit - Google Patents

Description

The field of the present invention is that of heat exchangers constituting a refrigerant fluid circuit equipping a motor vehicle. The subject of the invention is a device for homogenizing the distribution of a refrigerant fluid inside the tubes of such a heat exchanger. A device according to the preamble of claim 1 is known from JP H4 371798 .

A motor vehicle is commonly equipped with a ventilation, heating and/or air conditioning installation for thermally treating the air present or sent inside a passenger compartment of the motor vehicle. To do this, such an installation is associated with a closed circuit inside which a refrigerant fluid circulates. The refrigerant circuit successively comprises a compressor, a condenser or gas cooler, an expansion device and a heat exchanger. The heat exchanger is housed inside the ventilation, heating and/or air conditioning installation to allow heat exchange between the refrigerant fluid and a flow of air circulating inside said installation, previously to delivery of the air flow inside the passenger compartment.

According to one mode of operation of the refrigerant circuit, the heat exchanger is used as an evaporator to cool the air flow. In this case, the refrigerant fluid is compressed inside the compressor, then the refrigerant fluid is cooled inside the condenser or gas cooler, then the refrigerant fluid undergoes expansion inside the expansion device and finally the refrigerant captures calories from the air flow inside the heat exchanger. The refrigerant, at the outlet of the expansion device and at the inlet of the heat exchanger, is in the two-phase state and is present in a liquid phase and a gaseous phase.

The heat exchanger comprises a collector box and a return box between which a bundle of tubes is interposed. During operation of the coolant circuit, the coolant is admitted inside the heat exchanger through an inlet that includes the header box. Then, the coolant flows between the collector box and the return box by borrowing the tubes of the bundle.

A general problem posed resides in a difficulty in supplying the tubes of the bundle in a homogeneous manner with regard to the different phases, liquid and gaseous, of the refrigerant fluid.

Indeed, a heterogeneity in the supply of coolant fluid to the tubes of the bundle generates a heterogeneity in the temperature of the air flow which passes through the heat exchanger. This heterogeneity is likely to induce untimely and undesired temperature differences between areas of the passenger compartment, which is detrimental.

The document US2015/0121950 proposes to house, inside the collector box, a device for homogenizing the distribution of the coolant inside the tubes of the bundle. This device comprises a duct which comprises a first end part in relation to a first inlet mouth for the refrigerant fluid inside the heat exchanger. The duct is arranged in a cylindrical tube comprising a peripheral wall provided with orifices. The holes are identical to each other. The refrigerant fluid is projected through the orifices made through the duct to circulate inside the tubes of the heat exchanger.

Such an organization is not optimal from the point of view of the homogenization of the distribution of refrigerant fluid inside the heat exchanger. More particularly, the tubes of the bundle furthest from the first end part are frequently undersupplied with refrigerant fluid.

This results in heterogeneity in the temperature of the air flow leaving the heat exchanger, which is unsatisfactory.

An object of the invention is to perfect the homogeneity of the distribution of refrigerant fluid inside the heat exchanger, in order finally to improve its efficiency and its output, with a view to delivering inside the passenger compartment air flow at the desired temperature.

Another object of the invention is to improve the distribution of refrigerant fluid inside the heat exchanger, including when the latter is present inside of the heat exchanger in two distinct phases, liquid and gas, in variable respective proportions.

Another object is to propose a device for distributing a coolant fluid inside the collector box, and inside the tubes of the bundle, which ensures an equivalent supply of coolant fluid to the tubes of the bundle, including those which are furthest from a coolant inlet window inside the duct, and for example from the first end part of the duct when the latter is provided with the window.

A device of the present invention is a device for homogenizing a distribution of the refrigerant fluid inside the tubes of a heat exchanger having the characteristics of claim 1.

• les orifices de premier type du premier groupe s'étendent sur deux tiers de la longueur du conduit et les orifices de deuxième type du deuxième groupe s'étendent sur un tiers de la longueur du conduit, à 5% près.
• les orifices sont répartis au moins en un premier groupe d'orifices de premier type présentant la première section de passage, en un deuxième groupe d'orifices de deuxième type présentant la deuxième section de passage, et en un troisième groupe d'orifices de troisième type présentant une troisième section de passage.
• la section de passage des orifices est une fonction croissante d'une distance prise entre la fenêtre et les orifices.
• la fonction est une fonction en escalier.
• le conduit comprend une première partie terminale pourvue de la fenêtre et une deuxième partie terminale qui est obturée.
• le conduit est cylindrique.

The homogenization device advantageously comprises any one at least of the following characteristics, taken alone or in combination:

• the orifices of the first type of the first group extend over two thirds of the length of the duct and the orifices of the second type of the second group extend over a third of the length of the duct, to within 5%.
• the orifices are divided at least into a first group of orifices of the first type having the first passage section, into a second group of orifices of the second type having the second passage section, and into a third group of orifices of third type having a third passage section.
• the passage section of the orifices is an increasing function of a distance taken between the window and the orifices.
• the function is a step function.
• the duct comprises a first end part provided with the window and a second end part which is closed.
• the duct is cylindrical.

The invention also relates to a heat exchanger comprising a header box housing at least one such homogenization device.

The invention also relates to a refrigerant circuit comprising at least one such heat exchanger.

The invention also relates to the use of such a heat exchanger as an evaporator housed inside a casing of a ventilation, heating and/or air conditioning installation fitted to a motor vehicle.

• la figure 1 est une illustration schématique d'un circuit de fluide réfrigérant comprenant un échangeur de chaleur de la présente invention,
• la figure 2 est une illustration schématique d'une première variante de réalisation de l'échangeur de chaleur illustré sur la figure 1,
• la figure 3 est une illustration schématique d'une deuxième variante de réalisation de l'échangeur de chaleur illustré sur la figure 1,
• la figure 4 est une vue schématique en perspective d'une première variante de réalisation d'un dispositif de distribution de fluide réfrigérant équipant l'échangeur de chaleur illustré sur les figures 2 ou 3,
• la figure 5 est une illustration du diamètre des orifices équipant le dispositif de distribution illustré sur la figure 4 en fonction d'une distance respective des orifices par rapport à une fenêtre équipant ledit dispositif,
• la figure 6 est une vue schématique en perspective d'une variante de réalisation ne faisant pas partie de la présente invention d'un dispositif de distribution de fluide réfrigérant équipant l'échangeur de chaleur illustré sur les figures 2 ou 3,
• la figure 7 est une illustration du diamètre des orifices équipant le dispositif de distribution illustré sur la figure 6 en fonction d'une distance respective des orifices par rapport à une fenêtre équipant ledit dispositif,
• la figure 8 est une vue schématique en perspective d'une variante de réalisation ne faisant pas partie de la présente invention d'un dispositif de distribution de fluide réfrigérant équipant l'échangeur de chaleur illustré sur les figures 2 ou 3,
• la figure 9 est une illustration du diamètre des orifices équipant le dispositif illustré sur la figure 8 en fonction d'une distance respective des orifices par rapport à une première partie terminale dudit dispositif.

Other characteristics, details and advantages of the invention will become apparent on reading the detailed description given below by way of indication in relation to the drawings of the appended plates, in which:

• the figure 1 is a schematic illustration of a refrigerant circuit comprising a heat exchanger of the present invention,
• the picture 2 is a schematic illustration of a first alternative embodiment of the heat exchanger illustrated in the figure 1 ,
• the picture 3 is a schematic illustration of a second alternative embodiment of the heat exchanger illustrated in the figure 1 ,
• the figure 4 is a schematic perspective view of a first variant embodiment of a refrigerant fluid distribution device fitted to the heat exchanger illustrated in the figure 2 Where 3 ,
• the figure 5 is an illustration of the diameter of the orifices fitted to the dispensing device illustrated in the figure 4 as a function of a respective distance of the orifices with respect to a window fitted to said device,
• the figure 6 is a schematic perspective view of an alternative embodiment not forming part of the present invention of a refrigerant fluid distribution device equipping the heat exchanger illustrated in the figure 2 Where 3 ,
• the figure 7 is an illustration of the diameter of the orifices fitted to the dispensing device illustrated in the figure 6 as a function of a respective distance of the orifices with respect to a window fitted to said device,
• the figure 8 is a schematic perspective view of an alternative embodiment not forming part of the present invention of a refrigerant fluid distribution device equipping the heat exchanger illustrated in the figure 2 Where 3 ,
• the figure 9 is an illustration of the diameter of the orifices fitted to the device illustrated in the figure 8 as a function of a respective distance of the orifices with respect to a first end part of said device.

The figures and their description expose the invention in detail and according to particular methods of its implementation. They can be used to better define the invention, if necessary.

On the figure 1 , there is shown a closed circuit 1 inside which a refrigerant fluid FR circulates. In the illustrated embodiment, the refrigerant circuit 1 successively comprises, in a direction SI of circulation of the refrigerant FR inside the refrigerant circuit 1, a compressor 2 for compressing the fluid FR refrigerant, a condenser or a gas cooler 3 for cooling the FR refrigerant fluid, an expansion member 4 inside which the FR refrigerant fluid undergoes expansion and a heat exchanger 5. The heat exchanger 5 is housed inside a box 6 of an installation 7 for ventilation, heating and/or air conditioning inside which a flow of air circulates. The heat exchanger 5 allows heat transfer between the refrigerant FR and the air flow FA coming into contact with it and/or passing through it, as illustrated in the figure 2 and 3 . According to the mode of operation of the refrigerant circuit 1 described above, the heat exchanger 5 is used as an evaporator to cool the air flow FA, during the passage of the air flow FA in contact and / or right through the heat exchanger 5.

On the figure 2 and 3 , the heat exchanger 5 comprises a header box 8 and a return box 9 between which a bundle of tubes 10, 10a, 10b is interposed. In its generality, the heat exchanger 5 extends parallel to a first plane P1 containing the header box 8, the bundle of tubes 10, 10a, 10b and the return box 9. The header box 8 overhangs the bundle of tubes 10, 10a, 10b, which are themselves located above the transmission box 9, in particular in the position of use of the heat exchanger 5 mounted inside the housing 6. In other words, according to this position of use, the collector box 8 is an upper box of the heat exchanger 5 while the return box 9 is a lower box of the heat exchanger 5. The air flow FA flows through the heat exchanger 5 in a direction preferably orthogonal to the foreground P1.

The tubes 10, 10a, 10b are for example straight and extend along a first general extension axis A1 between the header box 8 and the return box 9. The header box 8 extends along a second extension axis general A2 and the transmission box 9 extends along a third axis of general extension A3. Preferably, the second general extension axis A2 and the third general extension axis A3 are mutually parallel, being orthogonal to the first general extension axis A1.

The bundle of tubes 10, 10a, 10b is provided with fins 15 which are interposed between two successive tubes 10, 10a, 10b, to promote heat exchange between the air flow FA and the tubes 10, 10a, 10b, when a passage of the air flow FA through the heat exchanger heat 5.

The heat exchanger 5 comprises a first mouth 16 through which the refrigerant fluid FR enters the interior of the heat exchanger 5. The first mouth 16 constitutes an inlet mouth for the refrigerant fluid FR in a first chamber 13 , which is delimited inside the collector box 8. The heat exchanger 5 comprises a second mouth 17 through which the refrigerant FR is evacuated from the heat exchanger 5.

On the picture 2 , the heat exchanger 5 is a heat exchanger inside which the refrigerant fluid FR flows along a path arranged in an “I”. The tubes 10 are arranged parallel to each other and each extend in a third plane P3 which is perpendicular to the first plane P1 and which is parallel to the first axis of general extension A1. The tubes 10 are moreover aligned forming a row which extends along a direction perpendicular to the third plane P3. The tubes 10 extend between a first end 101 which is in fluid communication with the return box 9 and a second end 102 which is in fluid communication with the header box 8. In other words, the return box 9 forms the base of the "I" while the manifold 8 forms the top of the "I". According to this first variant, the second mouth 17 equips the return box 9.

During an implementation of the refrigerant circuit 1, the refrigerant fluid FR enters the interior of the heat exchanger 5 through the first mouth 16 that includes the collector box 8. Then, the refrigerant fluid FR is distributed along the collector box 8 along the second axis of extension A2 by a device 18 for homogenizing the distribution of refrigerant fluid. Next, the refrigerant fluid FR flows between the header box 8 and the return box 9 via the tubes 10. Finally, the refrigerant fluid FR is evacuated from the heat exchanger 5 through the second mouth 17 of the diverter box 9.

On the picture 3 , the heat exchanger is a heat exchanger inside which the refrigerant fluid FR flows along a path arranged in a “U”. The tubes 10a, 10b are arranged parallel to each other, being distributed according to two layers 11, 12, of which a first layer 11 of first tubes 10a and a second layer 12 of second tubes 10b. The first ply 11 and the second ply 12 are arranged inside respective planes which are parallel to each other and parallel to the first plane P1.

The first tubes 10a of the first layer 11 extend between a first end 101 which is in fluid communication with the return box 9 and a second end 102 which is in fluid communication with the first chamber 13. The second tubes 10b of the second ply 12 extend between a third end 103 which is in fluid communication with the return box 9 and a fourth end 104 which is in fluid communication with a second chamber 14, also delimited inside the header box 8. The first chamber 13 and the second chamber 14 are contiguous and sealed with each other. The first chamber 13 extends along a fourth axis of general extension A4 and the second chamber 14 extends along a fifth axis of general extension A5. Preferably, the fourth axis of general extension A4 and the fifth axis of general extension A5 are parallel to each other and parallel to the second axis of general extension A2. The fourth axis of general extension A4 and the fifth axis of general extension A5 together define a second plane P2, which is preferably orthogonal to the first plane P1. In other words, the return box 9 forms the base of the "U" while the first layer 11 and the second layer 12 of tubes 10a, 10b form the branches of the "U", the first chamber 13 and the second chamber 14 forming the ends of the "U". According to this second variant, the second mouth 17 equips the second chamber 14 of the header box 8.

During an implementation of the refrigerant circuit 1, the refrigerant fluid FR penetrates inside the heat exchanger 5 through the first mouth 16 of the first chamber 13, being distributed along the box manifold 8 along the second axis of general extension A2 by the device 18 for homogenizing the distribution of coolant. Then, the refrigerant fluid FR flows between the first chamber 13 of the collector box 8 and the return box 9 by borrowing the first tubes 10a of the first layer 11. Then, the refrigerant fluid FR flows between the box of reference 9 and the second chamber 14 by borrowing the second tubes 10b of the second layer 12. Finally, the refrigerant FR is evacuated from the heat exchanger 5 through the second mouth 17, after having circulated through the second chamber 14.

Preferably, a first tube 10a of the first layer 11 is aligned with a second tube 10b of the second layer 12 inside the third plane P3 which is perpendicular to the first plane P1 and which is parallel to the first axis of general extension A1.

Whatever the alternative embodiment of the heat exchanger 5 presented above, the collector box 8 houses the device 18 for homogenizing the distribution of the refrigerant fluid FR inside the tubes 10, 10a, 10b. Such a device 18 for homogenizing the distribution of refrigerant fluid aims to evenly distribute the refrigerant fluid FR, in the two-phase liquid-gas state, along the manifold 8 and ultimately inside the set of tubes 10, 10a, 10b. Such a device 18 for homogenizing the distribution aims more particularly to distribute the refrigerant fluid FR homogeneously inside the heat exchanger 5, including when the refrigerant fluid FR is present inside the heat exchanger. heat exchanger 5 in two distinct phases, liquid and gas, in variable respective proportions.

On the figure 4 , 6 and 8 , the device 18 for homogenizing the distribution comprises for example a duct 19 extending along a sixth axis of general extension A6, parallel, or even coincident, with the second axis of general extension A2 and/or the fourth axis of general extension A4, between a first terminal part 20 and a second terminal part 21 of the conduit 19. The conduit 19 has a length L taken between the first terminal part 20 and the second terminal part 21, parallel to the sixth general extension axis A6. Preferably the length L of the conduit 19 is equivalent to a length of the header box 8 taken along the second axis of general extension A2 and/or to a length of the return box 9 taken along the third axis of general extension A3 .

It will be noted that any element which extends along the sixth axis of general extension A6 which is defined by the largest dimension of the conduit 19 is qualified as longitudinal. 'a transverse plane Pt which is orthogonal to the general extension axis A6.

The first end part 20 is formed from one end of the duct 19, while the second end part 21 is formed from the other end of the duct 19, longitudinally opposite the first end part 20.

According to a variant embodiment, the first terminal part 20 is intended to be placed in fluid communication with the first mouth 16 of the heat exchanger 5. According to another variant embodiment, the first mouth 16 houses the duct 19 whose first end part 20 is placed in fluid communication with a pipe of the refrigerant circuit 1. According to these two variants, the second end part 21 is blind and forms a cul-de-sac with regard to the circulation of the refrigerant fluid FR at the inside of duct 19.

According to the invention, the conduit 19 is equipped with at least one window 29 through which the refrigerant fluid FR is able to be admitted inside the conduit 19. Preferably again, the window 29 equips the first terminal part 20 According to another alternative embodiment, the window 29 equips any zone of the duct 19 taken between the first end part 20 and the second end part 21.

The duct 19 is for example shaped like a cylinder, or even like a parallelepiped or even like any other shape having an axis of symmetry A7, which is preferably parallel, or even coincident, with the sixth axis of general extension A6. The duct 19 comprises a peripheral wall 23 which is of cylindrical cross-section when the duct 19 is shaped like a cylinder, of parallelepiped cross-section when the duct 19 is a parallelepiped. The peripheral wall 23 is the one which gives the overall shape of the conduit 19.

The duct 19 constitutes an envelope which delimits an internal space 24 around which the duct 19 is formed. In other words, the conduit 19 borders the internal space 24 that the conduit 19 surrounds. Depending on the shape of the duct 19, the internal space 24 is for example cylindrical or else parallelepipedic, or else of any other shape provided around the axis of symmetry A7.

The peripheral wall 23 comprises orifices 22 which are made through the peripheral wall 23 of conduit 19. The orifices 22 are preferably aligned along an alignment axis A8 which is parallel to the sixth axis of general extension A6 and/or to the axis of symmetry A7.

According to a variant, the orifices 22 are equidistant from each other. According to another variant, the orifices 22 are separated from each other by a variable distance. The orifices 22 are, for example, orifices of circular section, but may be of any conformation, rectangular, elliptical, oblong in particular.

Each orifice 22 offers the refrigerant fluid FR a passage section D through which the refrigerant fluid FR flows to circulate from the internal volume 24 of the conduit 19 out of the latter, that is to say towards the volume delimited by the collector box 8. In other words, each orifice 22 has a passage section D which is the surface that the refrigerant fluid FR is able to cross during its evacuation from the conduit 19. The passage section D is defined as a surface of the orifice 22 taken along an orifice plane P4 which contains the orifice 22 and which is parallel to the sixth axis of general extension A6. When the duct 19 is cylindrical, the orifice plane P4 is a plane tangential to the duct 19 which comprises at least one orifice 22. By way of example, when the orifice 22 is of circular section, the passage section D is formed into a circle.

In general, conduit 19 is provided with N orifices 22, with N≥2. In other words, conduit 19 is equipped with at least two orifices 22. Preferably, the number N of orifices 22 is of the order of a number of tubes 10, or a number of first tubes 10a, or a number of second tubes 10b of the heat exchanger 5. Preferably, the number N of the orifices 22 is equal to the number of tubes 10, or a number of first tubes 10a, or a number of second tubes 10b of the heat exchanger 5.

According to the present invention, at least two of the N orifices 22 are of a respective passage section D which are distinct from each other. In other words, among the N orifices 22 that the duct 19 comprises, at least two of them have a passage section D for the coolant which is distinct from one another.

According to a first embodiment illustrated in the figure 4 , the orifices 22 are divided into first type orifices 22a having a first passage section D1 and second type orifices 22b having a second passage section D2, separate from the first passage section D1. Thus, among the N orifices, at least two orifices of the first type 22a have a first passage section D1 and at least two orifices of the second type 22b have a second passage section D2, which is greater than the first passage section D1. By way of example, the second passage section D2 is between 1.5 times the first passage section D1 and twice the second passage section D1.

According to a variant, among the N orifices, X first type orifices 22a have a first passage section D1 and Y second type orifices 22b have a second passage section D2, with N=X+Y. In other words, the orifices 22 are divided into a first group G1 of first type orifices 22a, preferably adjacent to each other, and a second group G2 of second type orifices 22b, preferably adjacent to each other. In other words again, the first group G1 has a number of X orifices of the first type 22a and the second group G2 has a number of Y orifices of the second type 22b, with N=X+Y.

For example, X represents two thirds of the number N of orifices 22 and Y represents one third of the number N of orifices 22. Thus, on the figure 4 , the conduit 19 comprises nine orifices 22, including six orifices of the first type 22a offering the refrigerant FR a first passage section D1 and three orifices of the second type 22b offering the refrigerant fluid FR a second passage section D2, which is greater than the first passage section D1. In other words, the first group G1 of orifices 22 has six orifices of the first type 22a and the second group G2 of orifices 22 has three orifices of the second type 22b.

According to an embodiment not forming part of the invention, illustrated in the figure 6 , the orifices 22 are divided into orifices of the first type 22a having a first passage section D1, in second type orifices 22b having a second passage section D2 and third type orifices 22c having a third passage section D3. Thus, among the N orifices, at least one first type orifice 22a has a first passage section D1, at least one second type orifice 22b has a second passage section D2 which is different from the first passage section D1 and at least one least one third type orifice 22c has a third passage section D3 which is different from the first passage section D1 and from the second passage section D2.

Preferably, the second passage section D2 is strictly greater than the first passage section D1 and the third passage section D3 is strictly greater than the second passage section D2. By way of example, the second passage section D2 is between 1.5 times the first passage section D1 and twice the first passage section D1, and the third passage section D3 is between 1.5 times the second passage section D2 and twice the second passage section D2.

According to a variant, among the N orifices, X orifices of the first type 22a have a first passage section D1, Y orifices of the second type 22b have a second passage section D2, Z orifices of the third type 22c have a third passage section D3 , with N=X+Y+Z. In other words, the orifices 22 are divided into a first group G1 of orifices of the first type 22a, adjacent to each other, into a second group G2 of orifices of the second type 22b, adjacent to each other, and in a third group G3 of third type orifices 22c preferentially adjacent to each other. In other words again, the first group G1 has a number of X orifices of the first type 22a, the second group G2 has a number of Y orifices of the second type 22b, and the third group G3 has a number of Z orifices of the second type 22c with N=X+Y+Z.

In a configuration not forming part of the invention, X represents a third of the number N of orifices 22, Y also represents a third of the number N of orifices 22 and Z also represents a third of the number N of orifices 22. Thus, on the figure 6 , the conduit 19 comprises nine orifices 22, including three orifices of the first type 22a providing the refrigerant FR with a first passage section D1, three orifices of the second type 22b providing the refrigerant fluid FR with a second passage section D2, which is strictly greater in the first section of passage D1 and three third-type orifices 22c providing the refrigerant FR with a third passage section D3, which is strictly greater than the second passage section D2. In other words, each of the groups G1, G2, G3 of orifices 22 has three orifices 22.

According to an embodiment not forming part of the invention, illustrated in the figure 8 , the orifices 22 have passage sections D1, D2, D3, ..... D9 all distinct from each other.

Preferably, the passage section Di, with i ∈ (1, ..., N ), of an orifice 22 is greater than the passage section Di-1 of the orifice 22 which adjoins it and which is closer of the window 29 and the passage section Di is lower than the passage section Di+1 of the orifice 22 which adjoins it and which is further from the window 29, the orifices 22 being listed from the window 29 towards the second part terminal 21.

et $$\exists i\in \left(1,\dots \mathrm{.},N-1\right)\mathit{tel}\mathit{que}\mathit{Di}<\mathit{Di}+1$$

According to another approach of the present invention, the orifices 22 cumulatively satisfy the following relations [1] and [2]: $$\mathrm{<figure-callout\; id="1"\; label="D"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">D</figure-callout>}1\le \mathrm{<figure-callout\; id="2"\; label="D"\; filenames="imgf0001.png"\; state="\{\{state\}\}">D</figure-callout>}2\le \mathrm{<figure-callout\; id="3"\; label="D"\; filenames="imgf0001.png"\; state="\{\{state\}\}">D</figure-callout>}3\dots \dots \dots \dots \le \mathrm{DN}$$

and $$\exists I\in \left(1,\dots \mathrm{.},\mathrm{NOT}-1\right)\mathit{Phone}\mathit{that}\mathit{Sun}<\mathit{Sun}+1$$

In other words, there is at least one ith orifice 22 whose passage section Di is strictly less than the passage section Di+1 of the i+1th orifice 22, adjacent to the ith orifice 22 and further away than the ith orifice 22 of the window 29.

In other words again, by traversing the orifices one by one from the window 29 to the first end part 20 or towards the second end part 21, the passage section of the orifices 22 is at least constant until one meets at least one orifice 22 whose passage section D exceeds the passage section D of the previous orifice 22.

• la première partie terminale 20,
• le premier orifice 22 de section de passage D1,
• le deuxième orifice 22 de section de passage D2,
• le troisième orifice 22 de section de passage D3,
• le ième orifice 22 de section de passage Di
• le (i+1)ième orifice 22 de section de passage Di+1
• le Nième orifice 22 de section de passage DN,
• la deuxième partie terminale 21,

les sections de passage susvisées vérifiant : $$\mathrm{<figure-callout\; id="1"\; label="D"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">D</figure-callout>}1\le \mathrm{<figure-callout\; id="2"\; label="D"\; filenames="imgf0001.png"\; state="\{\{state\}\}">D</figure-callout>}2\le \mathrm{<figure-callout\; id="3"\; label="D"\; filenames="imgf0001.png"\; state="\{\{state\}\}">D</figure-callout>}3\dots \dots \mathrm{Di}<\mathrm{Di}+1\dots \dots .\le \mathrm{DN}$$

Avec i ∈ (1, ... . , N - 1)Successively and linearly step by step, the duct 19 includes for example:

• the first terminal part 20,
• the first orifice 22 of passage section D1,
• the second orifice 22 of passage section D2,
• the third orifice 22 of passage section D3,
• the ith orifice 22 of passage section Di
• the (i+1)th orifice 22 of passage section Di+1
• the Nth orifice 22 of passage section DN,
• the second terminal part 21,

the passage sections referred to above verifying: $$\mathrm{<figure-callout\; id="1"\; label="D"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">D</figure-callout>}1\le \mathrm{<figure-callout\; id="2"\; label="D"\; filenames="imgf0001.png"\; state="\{\{state\}\}">D</figure-callout>}2\le \mathrm{<figure-callout\; id="3"\; label="D"\; filenames="imgf0001.png"\; state="\{\{state\}\}">D</figure-callout>}3\dots \dots \mathrm{Sun}<\mathrm{Sun}+1\dots \dots .\le \mathrm{DN}$$

With i ∈ (1, ... . , N - 1)

More particularly, the passage section Di of the orifices 22 follows a function F, which is an increasing function of a distance Wi taken between the window 29 and a center C of each orifice 22. The window 29 preferentially equipping the first end part 20 of the duct 19, the distance Wi of the orifices 22 is preferably measured between the window 29 and the center of the orifice 22. It follows from these provisions that, by considering two successive orifices 22, the orifice 22 furthest from the window 29, that is to say located at a second distance W2 from the window 29, has a passage surface D which is greater than or equal to the passage surface D of another orifice 22 closest to the window 29 , that is to say located at a first distance W1 from the window 29.

According to a first embodiment, the function giving the passage surface D of the orifices 22 as a function of the distance W between the window 29 and the orifices 22 is a staircase function, as illustrated in the figure 5 and 7 .

The linear function of the distance W, as shown in the figure 9 does not form part of the invention.

In general, the conduit 19 is capable of being provided with orifices 22 divided into a plurality of successive groups G of orifices, the orifices 22 of the same group being of the same passage surface D (at manufacturing tolerance close), the diameter of the orifices 22 of the successive groups being increasing from one group to another.

These arrangements are such that the refrigerant fluid FR penetrating inside said device is distributed homogeneously to all of the tubes 10, 10a, 10b, including those supplied by the orifices 22 furthest from the window 29, and/or the first part 20 provided with the window 29, due to the increase in the diameter of these orifices 22.

In other words, the small size of the orifices 22 arranged near the window 29, or of the first end part 20 equipped with the window 29 prevents the refrigerant fluid FR from preferentially borrowing the tubes 10, 10a, 10b supplied by the orifices 22 closest to window 29, so that a sufficient quantity of refrigerant fluid FR continues its path inside said homogenization device 18 to supply all of the tubes 10, 10a, 10b in a homogeneous manner, and especially those located furthest from window 29.

Claims (7)

1. Distribution homogenizing device (18) for homogenizing the distribution of the refrigerant (FR) inside tubes (10, 10a, 10b) of a heat exchanger (5), the homogenizing device (18) comprising at least one pipe (19) provided with N orifices (22, 22a, 22b, 22c) of respective bore section (D1, D2, D3, ..., DN) for the passage of the refrigerant (FR), where N ≥ 2, these including at least one orifice of a first type (22a) having a first bore section (D1) and at least one orifice of a second type (22a) having a second bore section (D2), such that the first bore section (D1) is smaller than the second bore section (D2), and that the orifices (22, 22a, 22b, 22c) are distributed in groups (G1, G2, G3), a group (G1, G2, G3) of orifices (22, 22a, 22b, 22c) being formed by at least two orifices (22, 22a, 22b, 22c) adjacent to one another and having identical bore sections (D1, D2, D3, ..., DN) to one another, in which, with the pipe (19) comprising at least one window (29) for admitting the refrigerant (FR), for any orifice of the first type (22a) being positioned at a first distance (W1) from the window (29), any orifice of the second type (22b) being positioned at a second distance (W2) away from the window (29), the first distance (W1) is smaller than a second distance (W2), in which the orifices (22, 22a, 22b, 22c) are distributed in at least one first group (G1) of orifices of the first type (22a), having the first bore section (D1), and a second group (G2) of orifices of the second type (22b) having the second bore section (D2), characterized in that the orifices of the first type (22a) of the first group (G1) extend over at least half the length (L) of the pipe (19) considered between a first end part (20) and a second end part (21) of the pipe (19).
2. Homogenizing device (18) according to Claim 1, in which the orifices of the first type (22a) of the first group (G1) extend over two thirds of the length (L) of the pipe (19) and the orifices of the second type (22b) of the second group (G2) extend over one third of the length (L) of the pipe (19), give or take 5%.
3. Homogenizing device (18) according to Claim 1, in which the orifices (22, 22a, 22b, 22c) are distributed in at least one first group (G1) of orifices of the first type (22a), having the first bore section (D1), a second group (G2) of orifices of the second type (22b) having the second bore section (D2), and a third group (G3) of orifices of a third type (22c) having a third bore section (D3) .
4. Homogenizing device (18) according to any one of the preceding claims, in which the bore section (D) of the orifices (22, 22a, 22b, 22c) is an increasing function of the distance (W) considered between the window (29) and the orifices (22, 22a, 22b, 22c).
5. Homogenizing device (18) according to any one of the preceding claims considered in combination with Claim 2, in which the pipe (19) comprises a first end part (20) provided with the window (29) and a second end part (21) which is closed off.
6. Homogenizing device (18) according to any one of the preceding claims, in which the pipe (19) is cylindrical.
7. Heat exchanger (5) comprising a header tank (8) housing at least one homogenizing device (18) according to any one of the preceding claims.

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