Patent Application
20180120033
The present invention concerns a stacked-plate heat exchanger, in particular a condenser allowing heat to be exchanged between a refrigerant and a coolant in the liquid phase.
In this field, heat exchangers comprising a heat exchange bundle comprising a series of plates stacked parallel to each other are known. The stack of plates forms heat exchange surfaces, between which a refrigerant and a coolant flow, in alternate layers, through fluid passage circuits. The stack of plates is therefore configured in such a way as to define two different circuits: the refrigerant circuit and the coolant circuit.
Known exchangers of this kind include exchangers further provided with a bottle for the refrigerant and a subcooling portion, located downstream from the bottle.
In this case, the stacked plates are separated into two portions, a cooling portion and a subcooling portion, and are provided with at least two refrigerant flow ports in communication with the bottle. Arranging these ports in a direction parallel to a longitudinal extension direction of said stacked plates is known.
However, positioning the flow ports in this way has the drawback of creating, on the surface of said plates, areas in which the flow of refrigerant, and therefore the exchange of heat between the refrigerant and the coolant, is low or indeed non-existent.
One of the aims of the invention is to solve the problem explained above by proposing a heat exchanger comprising a plurality of stacked plates intended to allow an exchange of heat between a first fluid and a second fluid flowing in contact with said plates, said exchanger comprising a bottle for the first fluid, said plates being provided with intermediate ports allowing the first fluid to flow between said plates and said bottle, said intermediate ports being arranged in a direction substantially transverse to a longitudinal main extension direction of the plates.
Thus, the direction of flow of said refrigerant being transverse to the direction in which the intermediate ports are aligned, the areas of low heat exchange are limited.
According to different embodiments, which can be taken together or separately:
The invention will be more clearly understood, and other aims, details, features and advantages of same will become clearer on reading the detailed explanatory description that follows, of at least one embodiment of the invention provided as a purely illustrative and non-limiting example, with reference to the appended schematic drawings:
The invention concerns a heat exchanger for exchanging heat between a first and a second fluid, in particular a condenser of an air conditioning circuit, more particularly in a motor vehicle.
Said first fluid is, for example, a refrigerant, such as the fluid known by the name R134a or that known by the name R1234yf. The heat exchanger is configured in such a way that said first fluid enters it in the gas phase and exits in the liquid phase. The second fluid is, for example, a coolant that can be water mixed with an antifreeze product such as glycol. In other words, the coolant can be a mixture of water and glycol.
As shown in
In other words, said stacked plates 3 are designed in such a way as to together define a first circuit for the flow of the first fluid and a second circuit for the flow of the second fluid, said circuits being designed to allow the first fluid to flow, avoiding the second circuit, and the second fluid to flow, avoiding the first circuit. Said first and second circuits respectively comprise the first fluid passages 7 and the second fluid passages 9.
As shown in
Said plates 3 each comprise two portions 130 and 150, a first portion 130 designed to allow an exchange of heat between the first fluid and the second fluid before the first fluid passes into the bottle 11, and a second portion 150 designed to allow an exchange of heat between the first fluid and the second fluid after the first fluid has passed into the bottle 11.
Said first 130 and second 150 portions of the plates 3 define, in the bundle, a first area 13 and a second area 15, respectively. In the case of a condenser, said first area 13 is a condensation area and said first area 15 is a subcooling area. It is noted that the bundle 1 is configured such that the first fluid cannot flow directly between the first fluid passages 7 of the first area 13 and those of the second area 15.
As shown in
Said plates 3 are, for example, obtained by chasing, punching and/or molding a rolled metal sheet, for example aluminum and/or an aluminum alloy.
Concerning said first fluid, said bottle 11 is connected upstream with said first area 13 of the bundle 1 and downstream with said second area 15 of the bundle 1. In other words, said heat exchanger is configured in such a way that said first fluid flows successively through said first area 13 of the bundle 1, said bottle 11 and said second area 15 of the bundle 1.
Said heat exchanger comprises an inlet manifold for the first fluid 19i, an outlet manifold for the first fluid 19o, an inlet manifold 18i for the second fluid and an outlet manifold 18o for the second fluid.
As shown in
Advantageously, the heat exchanger is configured such that said first fluid enters the bundle 1 through said first fluid inlet manifold 19i. Said first fluid next flows through the first area 13, then flows through the bottle 11 and returns to the bundle 1 where it flows through the second area 15. Said first fluid finally exits said bundle 1 through the first fluid outlet manifold 19o.
Advantageously, unlike for the first fluid, said bundle 1 is configured such that said second fluid flows through the bundle 1 directly from one of said first 130 and second 150 areas to the other, without passing through the bottle 11. In this case, the direction of flow of the second fluid is substantially the same in the whole bundle 1.
The bottle 11 extends advantageously parallel to said upper side 17 of the bundle 1. Said bottle 11 is located in this case between said manifolds 19i, 19o. Therefore, depending on the length available for the bottle 11, the cross section of the bottle 11 is adapted to obtain the desired volume. This possibility of varying the volume of the bottle 11 by varying its cross section means the manifolds 19i, 19o are more easily accessible. This configuration allows a high level of integration and the use of a bottle 11 that is easy to manufacture.
Said heat exchanger can also, for example, comprise a reinforcement plate 49 on said upper side 17.
As shown in
Advantageously, the number of said passes 25a, 25b, 25c, is odd so as to optimize the relative location of the bottle 11 and the first fluid inlet 19i.
Said heat exchanger comprises, in this case, collectors for the first fluid configured to allow said first fluid to flow from one of said first fluid passages 7 to the next first fluid passage 7, while avoiding the second fluid circuit. Similarly, said heat exchanger 1 is provided with collectors for the second fluid configured to allow said second fluid to flow from one of said second fluid passages 9 to the next second fluid passage 9, while avoiding the first fluid circuit.
Said collectors are defined by ports with which said plates 3 are provided. Each collector is arranged through the plates 3. In particular, each collector advantageously has a longitudinal main extension direction parallel to the stacking direction 5 of the plates 3. In other words, said collectors are arranged parallel to the stacking direction 5 of the plates 3. More specifically, said bundle 1 comprises an inlet collector for the first fluid to enter the first area 13, referred to as the main inlet collector 51a, said main inlet collector 51a being connected to the first fluid inlet manifold 19i. Said bundle 1 also comprises an outlet collector for the first fluid to exit the first area 13, referred to as the first intermediate collector 55, connected to the bottle 11. Said bundle 1 also comprises an inlet collector for the second fluid to enter the first area 13, connected to the second fluid inlet manifold 18i.
Said bundle 1 further comprises an inlet collector for the first fluid to enter the second area 15 from the bottle 11, referred to as the second intermediate collector 51b, connected to the bottle 11. Said bundle 1 also comprises an outlet collector 51c for the first fluid to exit the second area 15, referred to as the main outlet collector 51c, connected to the first fluid outlet manifold 19o. Said bundle 1 also comprises an outlet collector for the second fluid connected to the second fluid outlet manifold 18o.
The first 55 and second 51b intermediate collectors are arranged in the bundle 1 between the first 13 and second 15 areas.
The main inlet collector 51a, the main outlet collector 51c, the inlet collector for the second fluid to enter the first area and the outlet collector for the first fluid to exit the second area are all arranged along side edges 18 of the bundle 1, parallel to the stacking direction 5 of the plates 3.
It is noted that the main inlet collector 51a is connected both to the first fluid inlet manifold 19i and to each of the first fluid passages 7 inside the first area 13 of the bundle 1. The main outlet collector 51c is connected both to the first fluid outlet manifold 19o and to each of the first fluid passages 7 inside the second area 15.
It is also noted that the first intermediate collector 55 allows the first fluid to flow from the first area 13 of the bundle 1 to the bottle 11. The second intermediate collector 51b allows the first fluid to flow from the bottle 11 to each of the first fluid passages 7 in the second area 15 of the bundle 1.
As shown in
The first, second and third intermediate collectors 55, 51b, 53 are thus arranged in the bundle 1 between the first area 13 and the second area 15, parallel to each other.
Advantageously, in order to allow the first fluid to flow through several passes in the first area 13, in this case, more specifically, through three passes, the main inlet collector 51a and the intermediate collector 53 each comprise a separation partition 57. Said separation partitions 57 are, for example, flat walls arranged in said collectors in an orientation transverse to the longitudinal main extension direction of said collector. Said separation partitions 57 are arranged so as to separate an internal space of said collector into longitudinal portions opposite each other in the longitudinal main extension direction of said collector. Said separation partitions 57 are configured to limit or indeed prevent the flow of the first fluid between said two portions of a collector, said portions being separated from each other by said separation partition 57.
Said separation partitions 57 are arranged in each collector 51a, 53 to generate said flow through several passes 25a, 25b, 25c, as a result of an offset, in the stacking direction, between the location of one of the separation partitions 57 in said main inlet collector 51a and the location of another of the separation partitions 57 in the third intermediate collector 53. Each separation partition 57 is configured to modify the direction of flow of said first fluid in the first area 13 of the bundle 1.
As shown in
In particular, said plates 3 comprise a first intermediate port 75 and a second intermediate port 69b that both allow the first fluid to flow between said plates 3 and said bottle 11. Said first intermediate port 75 corresponds to the collector 55 while said second intermediate port 69b corresponds to the collector 51b.
According to the invention, said first and second intermediate ports 69b and 75 are aligned in a direction substantially transverse and/or orthogonal to the longitudinal main extension direction of the plates 3. In other words, said first and second ports 69b and 75 are centered on a straight line substantially transverse and/or orthogonal to the general and/or average direction of flow of the first fluid.
In the case of a heat exchanger with several passes, the plates 3 further comprise an additional port 73 referred to as the third intermediate port 73, said third intermediate port 73 allowing a flow through the passes and being aligned with said first 75 and second 69b intermediate ports. Said third intermediate port 73 corresponds in this case to the third intermediate collector 53.
The alignment of said intermediate ports 69b, 75, 73 along a straight line substantially transverse or orthogonal to a general direction of flow of the first fluid helps avoid the creation of one or indeed several areas at which the flow, and therefore the exchange of heat, is low or indeed non-existent. This arrangement of said intermediate ports 69b, 75, 73 allows a better use of space by maximizing the heat exchange areas.
Said intermediate ports 69b, 73, 75 are advantageously oblong and elongate in shape in a longitudinal extension direction of the plate 3. Each of said intermediate ports 69b, 73, 75 advantageously extends between two longitudinal ends of said port opposite each other in said longitudinal main extension direction of the plate. Said intermediate ports 69b, 73, 75 have a width, measured in a direction transverse to said longitudinal main extension direction, that reduces over virtually the whole length of the port between the two longitudinal ends. The part of the port having the greatest width is located upstream from the part of the port having the smallest width, in the direction of flow of the second fluid.
In other words, said intermediate ports 69b, 75, 73 are bulb-shaped, the widest part being located upstream from the narrowest part in the direction of flow of said second fluid.
This shape of said intermediate ports 69b, 75, 73 helps reduce head losses generated by the flow of the second fluid over the plates 3 at said intermediate ports 69b, 75, 73.
Said plates 3 comprise several types of plates 3, including primary plates 3a, shown in
Said plates 3 are used in pairs, each pair of plates 3 comprising one of the primary plates 3a and one of the secondary plates 3b.
In particular, concerning the first fluid circuit, each first fluid passage 7 is defined by a flow space between the front face of one of the primary plates 3a and the back face of one of the secondary plates 3b, said two primary 3a and secondary 3b plates being adjacent to each other. Concerning the second fluid, each second fluid passage 9 is defined by a flow space between the front face of one of the secondary plates 3b and the back face of one of the primary plates 3a, said two primary 3a and secondary 3b plates being adjacent to each other.
In the case of a secondary plate 3b, each of the first 73, second 69b and third 75 intermediate ports is located respectively in a pressed area forming a domed region 73′, 69b′ and 75′, each of said domed regions 73′, 69b′ and 75′ being arranged inside a flat region 67 forming a bottom of the plate. It is moreover noted that each secondary plate 3b is designed such that said second fluid can flow, on the front face of said plate, at the flat region 67 between said domed regions 73′, 69b′ and 75′ surrounding each port 73, 69b, 65 and directly from the first portion 130 to the second portion 150 of said secondary plate 3b. In other words, said secondary plate 3b is designed such that said second fluid can flow, on its front face, from the first portion 130 to the second portion 150 of said plate, bypassing each of the ports 73, 69b, 75 and therefore without flowing into the collectors 51b, 55 and 53.
Said three domed regions 69b′, 75′ and 73′ of the secondary plate are intended to correspond respectively with flat regions 69b″, 75″ and 73″ of an adjacent primary plate 3a. In other words, said domed regions 69b′, 75′ and 73′ and said flat regions 69b″, 75″ and 73″ are intended, once the plates 3 are stacked on each other, to be in contact.
In each of the primary plates 3a, said intermediate ports 69b, 75 and 73 are each arranged respectively inside said flat regions 69b″, 75″ and 73″. Advantageously, said flat regions 69b″, 75″ and 73″ each have a shape substantially identical to and dimensions slightly larger than each intermediate port. In other words, on the primary plates 3a, each of said flat regions 69b″, 75″ and 73″ surrounds the corresponding intermediate port 69b, 75 and 73.
Said flat regions 69b″, 75″ and 73″ of the primary plates 3a are substantially identical in shape and dimensions to the domed regions 69b′, 75′ and 73′ of the secondary plates 3b, so as to facilitate the joining together of the flat regions 69b″, 75″ and 73″ and domed regions 69b′, 75′ and 73′.
In particular, the front face of said domed regions 69b′, 75′ and 73′ of each secondary plate 3b is configured to be in contact with the back face of the region of the flat regions 69b″, 75″ and 73″ of an adjacent primary plate 3a.
The primary plates 3a can be further distinguished as primary plates of a first type 3a′ shown in
The pairs of plates of the first type are configured to allow the first fluid to flow through the passes 25a and 25b, and indeed 25c. The pairs of plates of the second type are configured to allow the first fluid to flow between the first and third intermediate collectors 53, 55, at the pass 25c. In other words, the passes 25a and 25b comprise pairs of plates 3 of the first type whereas the pass 25c comprises at least one pair of plates 3 of the second type and, optionally, pairs of plates of the first type.
It is noted that the secondary plates 3b are advantageously identical in all the passes and therefore the type of pairs of plates 3 is unimportant, unless provided with a partition 57, as discussed in greater detail below.
In both types of pairs, the primary plate 3a is provided on its front face with a pressed area formed from a domed region 65 intended to be in contact with the back face of a secondary plate 3b, at said flat region 67 of the latter. It is noted that said domed region 65 of the primary plate 3a is arranged between the first 130 and second 150 portion of said plate 3a, at the intermediate ports 69b, 75, 73. Similarly, the flat region 67 of the secondary plates 3b is arranged between the portion 130 and the portion 150.
In particular, said domed region 65 extends in a substantially transverse direction from one of the side edges 34 to the other of the side edges 34 of the primary plate 3a, such that said first fluid is prevented from passing directly from the first area 13 to the second area 15.
In pairs of the first type, said domed region 65 of the primary plate of the first type 3a′ and said flat region 67 of the secondary plate are designed such that, when joined together, they prevent the first fluid from flowing between both the first portion 13 and the second intermediate port 69b and the first intermediate port 75, while allowing the first fluid to flow between the first area 13 and the port 73 and between the second intermediate port 69b and the second area 13.
In other words, said domed region 65 of the primary plate of the first type 3a′ and said flat region 67 of the secondary plate 3b are designed such that, when joined together, they prevent the first fluid from flowing between the first area 13 of the bundle 1 and the first and second intermediate collectors 55, 51b.
More specifically, in the plates 3 of the pairs of the first type, said domed region 65 first bypasses the flat region 69b″ and said second intermediate port 69b in such a way as to isolate said second intermediate port 69b from the first portion 13. The port 75 and the flat region 75″ are then completely surrounded by the domed region 65 such that said port 75 is designed to be isolated from both the first portion 13 and the second portion 15. Finally, the domed region 65 bypasses the flat region 73″ and the third intermediate port 73 in such a way as to separate said third intermediate port 73 from the second portion 15 of the primary plate of the first type 3a′.
The pairs of the second type, i.e. those arranged in the final pass 25c, differ from the pairs of the first type in that, in this case, said domed region 65 of the primary plate of the second type 3a″ is this time designed such that, in joining together with the flat region 67 of the secondary plate 3b, it allows the first fluid to flow directly between the first area 13 and the first intermediate collector 55. In other words, the primary plates of the second type 3a″ are designed so as to provide a passage between the first area 13 and the bottle 11.
More specifically, in the plates of the pairs of the second type, said domed region 65 of the primary plate of the second type 3a″ first bypasses the flat region 69b″ and said second intermediate port 69b in such a way as to isolate said second intermediate port 69b from the first portion 13. The flat region 75″ and the first intermediate port 75 are then separated from the second portion 15 of the primary plate of the second type 3a″ by the domed region 65. Finally, the flat region 73″ and the third intermediate port 73 are also separated from the second portion 15 of the primary plate of the second type 3a″ by said domed region 65.
In
The flow of the second fluid is not affected by the type of pair of plates 3. A same type of passage is defined guiding the second fluid from the second fluid inlet collector to the second fluid outlet collector.
Generally, it is observed that the flow of each fluid within a pair of plates is constrained by the joint between the front face of a domed region of one of the plates 3 and the back face of a flat region of an adjacent plate 3, said fluid being forced to bypass said joint. In other words, the contact area between one of the domed regions and the flat surface is inaccessible to said first and second fluids.
It is also noted that said domed region 65 is designed to prevent the first fluid from flowing directly from one collector to another. In other words, said domed area 65 is further designed in such a way as to prevent the first fluid from flowing, between two plates 3 of a given pair, from one intermediate port to another intermediate port, except at pairs of the second type.
Said plates 3 can moreover be provided with corrugations 77 on the bottom of the plate arranged so as to create disturbances in the fluids and/or contacts points between the plates 3. Said corrugations thus help improve the exchange of heat between the first fluid and the second fluid.
Alternatively, as shown in
As a variant, as shown in
Advantageously, the other features of the single-pass heat exchanger are similar to those of the three-pass heat exchanger.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1553779 | Apr 2015 | FR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2016/058974 | 4/22/2016 | WO | 00 |
