JP2020529572A - Heat exchanger with multi-channel dispersion element - Google Patents

Abstract

The present invention is a heat exchanger comprising a dispersion element (22) configured to be disposed within at least one dispersion region (20) of the plate-fin heat exchanger (1), wherein the dispersion element ( 22) was arranged such that when the dispersion elements were arranged within the dispersion region (20), the dispersion region (20) was divided into a plurality of channels (26) for the flow of the fluid (F1). It relates to a heat exchanger including a plurality of dividing walls (25). According to the present invention, the channel (26) defines flow paths of different lengths and has a fluid passage cross section that varies along the flow path. [Selection diagram] FIG. 5B

Description

The present invention relates to a dispersion element configured to be located within the dispersion area of a plate and fin type heat exchanger, and such a dispersion element and fluid to have a heat exchange relationship with at least one other fluid. With respect to a heat exchanger containing at least one set of passages for. The elements according to the invention allow for a more uniform dispersion of the fluid over the width of the passage.

The present invention has been found to be particularly useful in the field of deep cold separation of gases, specifically deep cold separation of air, in what is known as an ASU (Air Separation Unit) used to generate pressurized gaseous oxygen. Is done. In particular, the present invention can be applied to heat exchangers that vaporize the flow of liquid by exchanging heat with gases such as oxygen, nitrogen and / or argon.

The present invention vaporizes at least one flow of a liquid-gas mixture, such as a mixture of hydrocarbons, specifically a multi-component mixture, through heat exchange with at least one other fluid, such as natural gas. It can also be applied to heat exchangers.

Commonly used techniques for heat exchangers are those of aluminum brazed plates and fin heat exchangers, which are extremely compact and allow the acquisition of devices that provide a large heat exchange surface area.

These heat exchangers include a plate, in which a heat exchange wave formed by a series of fins or corrugated legs is inserted between the plates, thereby forming a stack of various fluid passages in a heat exchange relationship. To do.

These passages include areas called dispersion areas, which are located in the entire direction of fluid flow in the passages of interest upstream and downstream of the actual heat exchange area. The dispersion area is fluid-connected to a semi-tubular header configured to selectively disperse the various fluids into the various passages and to remove the fluid from the passages.

In a known method, these dispersers usually include a distributed wave type that is arranged in the form of a corrugated sheet between two continuous plates. The distributed wave type is usually a perforated straight wave type cut into a triangular or trapezoidal shape. The dispersed wave type diverts the fluid coming from the inlet header of the heat exchanger to spread over the width of the heat exchange area and recovers the fluid coming from the heat exchange area. The dispersed wave type also serves as a spacer to ensure mechanical integrity during brazing and operation of the distributed area of the passage. Such dispersed wave types are known from US Pat. No. B-6,044,902 and European Patent Application Publication No. A-0507649. Also known from European Patent Application Publication No. A-3150952 is a plate heat exchanger in which the dispersion elements are formed by actual plates (these are pressed).

One of the problems that arises with the current distribution zone configuration is poor dispersion of fluid towards the heat exchange zone. Specifically, the dispersed area is occupied by at least two corrugated pads to optimize cutting debris from the shaping process, thus increasing the risk of clearance between these pads. Assembling the corrugated pad can also cause accidents along the fluid flow path, which contributes to increased pressure drop in the dispersion area. Due to these imperfections within the distributed area, flow rate fluctuations with an amplitude of about 10% can occur, which is detrimental to the correct operation of the heat exchanger.

Similarly, dispersion defects are found in the dispersion area used to recover the fluid coming from the heat exchange area.

Another issue concerns the mechanical integrity of distributed areas. Specifically, these areas have a lower density than that of the heat exchange areas, typically a wavy shape with 6-10 legs per inch. Currently, the dispersion area of the passage is typically about 200-600 mm long (measured in the vertical direction corresponding to the direction of fluid flow within the heat exchange area of the same passage) and about 500-1500 mm. Extends over a width (measured perpendicular to the longitudinal direction). Since the dispersion area constitutes a portion with lower mechanical integrity than the heat exchange area, its longitudinal direction is to ensure better resistance of the heat exchanger during the circulation of fluid at high pressure in the passage. It is desirable to limit the spread as much as possible.

An object of the present invention is to provide a heat exchanger in which the dispersion of the fluid in the heat exchange zone is as uniform as possible, and the heat exchanger also has a dispersion zone that occupies a space smaller than that of the prior art. It is to solve the above-mentioned problems completely or partially.

Therefore, the solution according to the invention is a brazed plate and fin type heat exchanger.
-Defines at least one set of fluid passages intended to exchange heat with at least one other fluid flowing through, extending in the longitudinal direction and in the lateral direction perpendicular to the longitudinal direction. With multiple plates arranged in a manner parallel to each other,
-Each passage divided into at least one dispersion area and one heat exchange area in the vertical direction,
-At least one dispersion area of the passage containing the dispersion element, wherein the dispersion element includes a plurality of dividing walls arranged so as to divide the dispersion area into a plurality of channels through which a fluid flows, and the channel is a channel. A heat exchanger that includes at least one dispersion area that defines channels of different lengths and has variable passages for fluid along the channels.

In some cases, the elements of the invention may include one or more of the following technical features:
− The dividing walls of the dispersion elements are fixed together via a support and
-The support is brazed to the adjacent plate.
-The split wall projects from the support into the passage.
-The support includes a flat bottom and the dividing wall projects perpendicular to the bottom.
-The element includes a first end forming an inlet or outlet for the fluid and a second end fluidly connected to the heat exchange area when the dispersion element is placed within the dispersion area, each split. The wall is made of a single component and extends continuously from the first end to the second end.
-Each channel has a first opening and a second opening located at the first and second ends, respectively.
-At least one first opening has a different fluid passage than the fluid passage of another first opening, and / or at least one second opening is of another second opening. It has a fluid passage that is different from the fluid passage.
-The first and / or second opening of the same channel has a fluid passage that becomes larger as the flow path defined by the channel becomes longer.
-One or more channels include means for correcting the linear flow resistance of said channel.
-The means include the shape of the internal profile of the channel.
-The means include a bulkhead disposed within the channel.
-The means include a porous structure disposed within the channel, such as a metal foam.
-The split wall has a linear profile in vertical section.
-The dividing wall has a predetermined curved profile in vertical section.
-The predetermined curve profile includes at least one inflection point.
-Dispersive elements extend along the longitudinal length and across the lateral width, with a ratio between length to width of less than 20%, preferably 5-10%.
-The dispersion element extends along a length of less than 500 mm, preferably 50-200 mm.
-The dispersion element has a height of at least 2 mm, preferably at least 5 mm, preferably 2 to 15 mm, measured perpendicular to the plate.
-The dispersion element is preferably a monolithic element produced by an additive manufacturing method or casting.

The present invention is better understood herein by the following description given here as a non-limiting example and with reference to the accompanying drawings.

It is a three-dimensional schematic diagram of a plate and fin type heat exchanger. It is a partial schematic view of the vertical cross section of the dispersion area by one Embodiment of this invention. It is a partial schematic view of the vertical cross section of the dispersion area by another embodiment of this invention. It is a partial schematic view of the vertical cross section of the dispersion area by another embodiment of this invention. It is the schematic and the three-dimensional schematic of the vertical cross section of the dispersion area by another embodiment of this invention. The results of a simulation performed using the dispersion elements schematically depicted in FIG. 5B are presented. The results of a simulation performed using the dispersion elements schematically depicted in FIG. 5B are presented.

As can be seen from FIG. 1, the plate and fin type heat exchanger 1 includes a stack of plates 2 extending in two dimensions, length and width in the longitudinal direction z and the lateral direction y, respectively. The plates 2 are spaced apart from each other and stacked in parallel with each other, and thus some of the passages 3, 4, 5 of the fluids F1, F2, F3 are in an indirect heat exchange relationship through the plate 2. Form a pair. The horizontal direction y is perpendicular to the vertical direction z and is parallel to the plate 2. Preferably, the vertical axis is vertical when the heat exchanger 1 is in operation.

Preferably, each passage has a flat and parallel hexahedral shape. The passage extends in the longitudinal direction z with respect to length and in the lateral direction y with respect to width. The distance between the two continuous plates is small compared to the length and width of each continuous plate.

Each passage 3, 4, 5 is divided into at least one dispersion zone 20 and one heat exchange zone 21 in the longitudinal direction z. The flow of fluid in the dispersed area as a whole occurs parallel to the longitudinal direction z. The dispersion area 20 and the heat exchange area 21 are preferably juxtaposed along the vertical axis z.

According to the description of FIG. 1, two dispersion zones 20 are arranged on both sides of the heat exchange zone 21, one of which is the fluid F1 in the heat exchange zone 21, with particular consideration given to the passage 3 whose interior is visible. It serves to carry in the direction and the other serves to drain the fluid F1 from the area. A conventional dispersed wave type made in the form of a wave product is shown in the dispersed area 20.

In a method well known per se, the heat exchanger 1 includes semi-tubular headers 7 and 9 with openings 10 for introducing the fluid into the heat exchanger 1 and discharging the fluid from the heat exchanger 1. These headers have openings that are not wider than the aisles. The dispersion zone 20 serves to disperse the fluid introduced through the opening into the header over the width of the passage.

According to the present invention, the dispersion element including the plurality of division walls 25 arranged so as to divide the dispersion area 20 into the plurality of channels 26 through which the fluid F1 flows is the at least one dispersion area of the passage 3 of the heat exchanger. It is arranged within 20. The channel 26 defines a flow path having different lengths and has a variable passage portion of fluid along the flow path. By subdividing the dispersion zone into multiple separate channels with variable length and cross section, it is possible to divert the fluid while finely controlling the flow conditions of the fluid within each channel. In particular, with a fluid velocity that is more or less identical at the outlet of each channel, and thus a uniform or quasi-uniform distribution of the fluid over the width of the passage at the outlet of the dispersion zone, while minimizing the pressure drop in the dispersion zone. It is possible to balance the velocities of fluids flowing through different channels so as to obtain.

In addition, the dispersion element provides structural rigidity over the dispersion area of the heat exchanger, as spacer function can be guaranteed by the split walls.

It should be noted that within the scope of the present invention, the heat exchanger is a brazed plate and fin type. Here, brazed plates and fin types mean that the separate elements that make up the heat exchanger are fixed directly or indirectly by brazing. The dispersion element according to the present invention is separated from the plate 2.

"Brazed support" is understood to mean that this support is connected or secured by brazing to the adjacent plate of the heat exchanger via at least a portion of its respective surface.

It should be noted that the expression "fluid passage" means the region through which the fluid flows through the channel. This is measured in a plane that is perpendicular to the direction of movement of the fluid F1 in the channel, i.e., perpendicular to the streamline of the moving fluid F1.

The length of the flow path is understood to be the distance covered by the fluid F1 between the inlet and outlet of the channel of interest.

According to the present invention, the dispersion element also includes a support 27 configured to maintain a wall 25 fixed together. An example of such an element is presented in FIG. 5B.

Therefore, it is understood that the dispersion element is not a corrugated product, as opposed to the dispersed wave, which is customarily placed within the dispersion area of the brazed plates and fin heat exchangers. The walls 25 are fixed together via the same support 27, thereby providing greater rigidity on the dispersion elements. This also makes it possible to simplify the brazing process. Moreover, such a configuration provides greater design freedom of the distributed elements and geometric freedom of their channels.

Therefore, it is possible to place a wall 25 in the aisle having a relatively large height, typically at least 2 mm, preferably at least 5 mm, more preferably at least 15 mm or more. This is not the case for heat exchangers where the walls result from the pressurization of the split plate.

Preferably, the support includes a bottom 27 on which the split wall 25 is to be erected, preferably a flat bottom that can be formed from a flat plate. The wall 25 is preferably erected in the vertical direction x. The wall 25 can typically have a height h of 2 to 15 mm. Preferably, the height is chosen so that the wall 25 extends vertically x over almost all, if not all, of the height of the passage.

The configuration of the dispersion element 22 which is a separate part from the plate according to the present invention also makes it possible to design different dispersion profiles on both sides of the same plate.

Preferably, the dispersion elements according to the invention are housed within some, if not all, of the dispersion areas of one or more sets of passages in the heat exchanger. The element extends over almost all, if not all, of the height of the passage (measured in the vertical x) such that the structure favorably contacts each plate 2 forming the passage 20.

The channels are preferably fluidly insulated from each other. Therefore, the flow parameters of each channel are controlled independently of those of the adjacent channels, which allows for precise adjustment of fluid distribution over the width of the passage at the exit of the dispersion area. Advantageously, the split wall 25 is erected perpendicular to the plate 2.

Preferably, the number of channels 26 is at least 6, more preferably 5-50. Specifically, the number of channels 26 needs to be large enough on the one hand to give the element 22 its mechanical stiffness, but on the other hand it has enough free volume to allow fluid to flow and limit the pressure drop. Don't be too much to leave.

Advantageously, the dispersion element 22 includes a first end 23 forming an inlet or outlet for the fluid F1 and a second end 24 fluidly connected to the heat exchange zone 21.

More specifically, as can be seen in FIG. 1, passages 3-5 are bounded by a block bar 6 that does not completely block the passage but leaves free openings 23, 24 at the inlet or outlet of the corresponding fluid. ..

FIG. 2 schematically partially depicts the "inlet" portion of the passage 3 of the heat exchanger according to one embodiment of the present invention. The fluid header 7 is located in the left hand corner of the heat exchanger, the first end 23 is fluidly connected to the header 7 to form the inlet of the fluid F1, and the fluid flow is outlined by the dashed arrows. Shown.

The first and second ends 23, 24 preferably extend in a plane parallel to the lateral direction y and perpendicular to the longitudinal direction z. The dividing wall 25 extends between the first end 23 and the second end 24. The split wall 25 forms a channel 26 that goes out at the second end 24. The split wall 25 provides uniform or semi-uniform dispersion in or from the full width direction of the heat exchange zone 21 when the fluid F1 is supplied to the other of the first end 23 and the second end 24. The fluid F1 is configured to be uniformly dispersed in the lateral direction y.

Advantageously, each channel comprises a first opening 26a and a second opening 26b. Advantageously, as outlined in FIG. 2, the first and second openings 26a, 26b are located at the first and second ends 23, 24, respectively, and the split wall 25 is the first. Continuously extends from the end 23 of the to the second end 24. The flow path of the fluid F1 corresponds to the path following the opening 26a and the opening 26b. Therefore, each of the ends 23, 24 can be divided into a series of openings 26a and a series of openings 26b, respectively.

The openings 26a, 26b of the channel 26 may have fluid passages that are the same or variable depending on the channel 26 of interest. The fluid passages of the openings 26a, 26b correspond to the internal region of the channel 26 measured at the first and second ends 23, 24 in the plane parallel to the lateral direction y.

Preferably, at least one first opening 26a has a fluid passage different from that of another first opening 26a, and / or at least one second opening 26b is another. It has a fluid passage that is different from the fluid passage of the second opening 26b.

Advantageously, the first opening 26a and / or the second opening 26b of the same channel 26 has a longer flow path defined by the channel 26, that is, the first opening 26a and the second opening 26b. It has a fluid passage that increases as the distance covered by the fluid F1 increases.

Therefore, in the example of FIGS. 3A, 3B or 5B in which the first end 23 is located at the polar edge of the element 22 along the direction y, the first end 23 is a fluid passage that increases laterally y. It is subdivided into the first opening 26a of the first series having. This facilitates the provision of a channel configured to disperse the fluid F1 from the header 7 towards a portion of the second end 23 that is diagonally opposite to the pole edge.

According to another example (FIG. 5A) in which the element 22 has a central surface M and the first end 23 is eccentric with respect to the surface M, the first is preferably arranged symmetrically on both sides of the surface M. The opening 26a has a fluid passage that increases with increasing distance from the central surface M.

This compensates for the original tendency of the fluid to enter the region of the dispersion zone located next to the header rather than through the zone further away from the header, thus homogenizing the dispersion of the fluid over the width of the heat exchanger passage 3. To do.

Advantageously, when the dispersion element 22 is placed within the dispersion area 20 of the heat exchanger, the first end 23 is positioned by the inlet header 7 of the heat exchanger to form the inlet of the fluid F1. The first opening 26a within the first end 23 has a fluid passage that is variable depending on their position along the lateral direction y.

By using openings 26a with different passages, it is particularly possible to oversupply into the dispersion zone 20 from a channel that is less favorable for the fluid passage, specifically the inlet of the fluid F1, which is more It causes less pressure drop and thus leads to a more efficient fluid dispersion system.

According to an advantageous embodiment of the present invention, all or some of the channels 26 include means 28 for correcting the linear flow resistance of the channel 26. Therefore, the linear flow resistance of each channel can be adjusted depending on the desired flow characteristics of each channel 26, particularly fluid flow rate and fluid flow rate. Therefore, the linear flow resistance of the channels can be adjusted so that each channel 26 has a similar overall flow resistance. Therefore, the properties of the fluid at the outlet of the channel 26 are homogenized in the lateral direction y, which allows uniform dispersion in or from the heat exchange zone 21.

The expression "flow resistance" is understood to mean the ability of the channel to divert the flow (pressing force perpendicular to the wall) as well as to generate viscous friction. This resistance is expressed in the form of the reaction force of the solid structure against the flow (unit Newton), resulting in a pressure drop in the fluid (unit Pascal). This force depends firstly on the kinetic energy of the fluid (rho × u ² ) and secondly on the Reynolds number (rho × u × D / μ). The linear flow resistance corresponds to the flow resistance of the channel expressed per unit length.

Advantageously, the channel 26 includes a correction means 28 configured such that the closer the opening 26a of the channel is to the other opening 26b, the greater the increase in linear flow resistance with respect to the distance covered by the fluid F1. .. For example, in the configuration shown in FIG. 3B, channel 26 includes modifying means 28 configured to generate a smaller increase in linear flow resistance in the lateral direction y. Specifically, this makes it possible to compensate for the inherently preferred passage of fluid along the axis rather than along the sides of the heat exchanger, and thus to obtain good dispersion of the fluid. When the header 7 is eccentric with respect to the central surface M of the heat exchanger, the fluid resistance of the channel becomes even greater closer to the central surface M, as shown in FIG. 5A.

Channel 26 may have an internal profile that is shaped to generate different variations in flow resistance.

Obstacles 28 that produce different flow resistances may be placed within one or more channels 26. Insertion of a porous structure 28, such as a metal foam, into a channel makes it possible to increase its flow resistance. Therefore, the linear flow resistance of the channel 26 may be adjusted by changing the volume, density and other characteristics of the inserted structure 28 according to the channel. In the example shown in FIG. 3B, the volume occupied by the porous structure 28 decreases laterally y to produce smaller linear flow resistance variations along the transverse y.

According to the generally illustrated example of FIG. 4, the partition wall 28 may be arranged within one or more channels 26 to create additional steps for dividing the dispersion area 22. This allows for varying linear flow resistance and finer control over the flow parameters of the fluid dispersed or recovered in the direction of the heat exchange zone 21. The use of the additional bulkhead 28 is particularly advantageous when the first end 23 of the dispersion element has a width that is too small to be split into a sufficient number of channels 26.

Optionally, the split wall 25 and / or partition wall 28 may have a linear profile as shown in FIGS. 2 and 4 or a curved profile as shown in FIGS. 3A, 3B and 5A, 5B in vertical cross section.

According to a particularly advantageous embodiment, the split wall 25 has a predetermined curve profile that includes at least one inflection point P.

Such geometry allows the fluid to divert more rapidly, i.e. over short distances L1, specifically over the large width of the heat exchanger passages. Therefore, increasing the compactness of what is known as the "weak" area of the heat exchanger reduces the longitudinal spread of the dispersion area 20 and thus increases the mechanical integrity of the heat exchanger. Is possible.

This also provides the possibility of reducing the width of the first end 23 of the dispersion element 22, and thus the width of the header 7, which is a relatively expensive component. Preferably, the first end 23 forming the inlet or outlet of the dispersion element 22 has a width L3 of 50 to 1000 mm, more preferably 100 to 500 mm in the lateral direction y.

Such a profile also makes it possible to reduce the pressure drop in the channel 26. Sudden changes in channel profile are known to result in fluid recirculation that causes pressure drops.

Preferably, the dispersion element 22 has a length L1 of less than 500 mm, preferably 50-200 mm, more preferably 80-100 mm parallel to the longitudinal direction z. Preferably, the length L1 of the dispersion element 22 represents less than 20% of the length of the heat exchange zone 21. Parallel to the lateral direction y, the dispersion element 22 has a width L2 and the ratio between the length L1 and the width L2 is less than 20%, preferably 5-10%. The width L2 is preferably 500 to 1500 mm.

The dispersion element 22 is advantageously formed from a metallic material, preferably aluminum or an aluminum alloy. The element can be formed, especially from a porous material, preferably by closed pores, such as a metal foam.

Preferably, the dispersion element 22 is monolithic, which makes it possible to minimize accidents along the flow path of the fluid.

The element 22 can be manufactured, preferably by thermal spraying, using an additional manufacturing method, allowing the integral production of parts with complex geometries. In particular, cold spray methods may be used.

It should be noted that the additive manufacturing method is sometimes referred to as "3D printing". Additive manufacturing makes it possible to manufacture real objects using specific printers that deposit and / or solidify material layer by layer to obtain final parts. The lamination of these layers makes it possible to generate a solid.

Element 22 can also be manufactured using the following additive manufacturing methods:
− Molten deposition modeling (FDM) methods, including modeling by deposition of molten material,
-Stereolithography (SLA): A method in which ultraviolet light solidifies a layer of liquid plastic, or-selective laser sintering in which a laser is used to coagulate a layer of powder.

Alternatively, the dispersion element 22 can be manufactured by casting. This manufacturing method makes it possible to produce parts with complex geometries at a relatively low cost compared to additive manufacturing. Preferably, the element 22 is formed from an aluminum alloy by casting, i.e., an alloy whose main constituent is aluminum, and has a lower density than that intended to be converted by the casting technique.

With respect to the heat exchange area 21 of the heat exchanger, they advantageously include a heat exchange structure 8 arranged between the plates 2 as shown in FIG. These structures have the function of increasing the heat exchange area of the heat exchanger and between the plates 2 during the assembly of the exchanger, especially by brazing, to avoid any deformation of the plate during use of the pressurized fluid. Serves as a spacer for.

Preferably, these structures preferably include a heat exchange wave type 8 that extends across the width and length of the heat exchanger passage and is parallel to the plate 2. These corrugated forms 8 can be formed in the form of corrugated sheets. In this case, the corrugated leg connecting the continuous top and the continuous bottom of the corrugation is called a "fin". The heat exchange structure 8 may also cover other specific shapes defined depending on the desired fluid flow characteristics. More generally, the term "fin" covers the main heat exchange surface, i.e. a blade or other secondary heat exchange surface that extends from the heat exchanger plate into the heat exchanger passage.

In the passage, the dispersion element 22 and the heat exchange structure 8 according to the present invention are preferably juxtaposed along the vertical axis z, that is, placed end to end. Note that there may be a small clearance between these elements as it does not block the channels of the heat exchange zone 21 facing the wall 25 of the channels of the dispersion zone 22. Preferably, the first end 23 of the element 22 is arranged end-to-end with at least a portion of the header 7, while the second end 24 is arranged end-to-end with at least a portion of the structure 8. Preferably, the structure 8, header 7 and / or element 22 are connected to the plate 2 by brazing and are indirectly connected to the plate 2 together via their respective connections. Advantageously, the element 22 is assembled onto the plate 2 by brazing the support 27 to the plate 2, and the support or bottom 27 comprises at least one surface coated with a brazing agent. This surface is located next to the plate 2 so that the plate 2 forms a connecting surface. Alternatively or additionally, the plate 2 has at least one surface completely or partially covered with a brazing agent layer.

To demonstrate the effectiveness of the dispersion element 22 according to the invention for uniformly dispersing the fluid, a fluid flow simulation was performed using the dispersion element according to FIG. 5B.

The dimensional characteristics of the dispersion element 22 were as follows:
-Element 22 length L1: 85 mm,
-Half width of element 22 L2 / 2: 485 mm,
-Width of the first end 23 forming the inlet L3: 370 mm,
-Mechanical clearance between dispersion element 22 and heat exchange structure 8: 2 mm,
-Height of element 22: 9.5 mm (wall 25 with a vertical x height of 7.5 mm and bottom 27 with a thickness of 2 mm),
-Wall 25 thickness: 2.3 mm.

For fluids, the simulation parameters were:
-Fluid properties: nitrogen,
-Fluid pressure at the outlet of dispersion element 22: 1.2 bar,
-Fluid temperature at the inlet of header 7: -80 ° C,
-Fluid temperature at the outlet of header 9: 1 ° C,
-Mass flow rate of fluid flowing through the heat exchanger passage: 100 kg / h.

The results of these simulations are presented in FIGS. 6A, 6B, 6C and 7. 6A, 6B and 6C show plots of velocity, pressure and temperature of fluid flowing through channel 26 of dispersion element 22. A semi-uniform dispersion of fluid is seen at the outlet of channel 26. FIG. 7 shows a change in the value of the axial flow velocity obtained at the exit of element 22, that is, what is known as the velocity in the longitudinal direction z, depending on the position in the lateral direction y. Therefore, this change begins at the center of the dispersion element 22 (position at 0 mm) and continues to the edge of the second end 23 (position at 485 mm). The variance of the velocity values along the lateral y is characterized by a standard deviation of 0.9% and a maximum deviation of 2.8% with respect to the mean velocity within the heat exchange area, which has a standard deviation of about 3 Much less than the variation found by the traditional variance factor of%. According to the present invention, the velocity variation is thus reduced laterally at the outlet of the dispersion zone, allowing the fluid to be dispersed as uniformly as possible over the width of the heat exchange zone.

Of course, the invention is not limited to the particular examples described and illustrated in this application. Other modifications or embodiments within the capabilities of those skilled in the art can also be considered without departing from the scope of the invention. For example, other directions and sensing of fluid flow in the heat exchanger are, of course, conceivable without departing from the scope of the invention. Therefore, the dispersion element according to the present invention is a heat exchanger in one or more series of passages 3, 4, 5 of one or more series of heat exchangers upstream and / or downstream of one or more headers of the heat exchanger. Can be placed within any distributed area of. For example, FIG. 5B shows the case where the heat exchanger passages include two dispersion elements according to the invention located on either side of the heat exchange zone 21 (scheduled by an intentionally shortened length). It should also be noted that the heat exchanger passages 3, 4 and 5 can be similarly well formed between the two continuous plates 2 and between the heat exchanger blockage bar 6 and the directly adjacent plates 2. Is.

Claims (17)

-A passage (3) of a fluid (F1) intended to exchange heat with at least one other fluid (F2) flowing through, with respect to the longitudinal direction (z) and said longitudinal direction (z). A plurality of plates (2) arranged in a manner parallel to each other so as to define at least one set of passages (3) extending in the vertical lateral direction (x).
-Each passage (3) divided into at least one dispersion area (20) and one heat exchange area (21) in the longitudinal direction (z).
-At least one dispersion area (20) of the passage (3) containing the dispersion element (22), the dispersion element (22) being dispersed in a plurality of channels (26) through which the fluid (F1) flows. Including a plurality of dividing walls (25) arranged to divide the area (20), the channel (26) defines channels of different lengths and a variable passage of fluid along the channels. In a brazed plate and fin type heat exchanger (1), including at least one dispersion area (20) having a portion.
The heat exchanger (1), characterized in that the dividing wall (25) of the dispersion element (22) is fixed together via a support (27) brazed to an adjacent plate (2). The heat exchanger according to claim 1, wherein the dividing wall (25) projects from the support (27) into the passage (3). The heat exchange according to claim 2, wherein the support (27) includes a flat bottom portion (27), and the dividing wall (25) projects perpendicularly to the bottom portion (27). vessel. When the first end (23) forming the inlet or outlet of the fluid (F1) and the dispersion element are placed in the dispersion area (20), they are fluidly connected to the heat exchange area (21). Each dividing wall (25) is formed from a single component and extends continuously from the first end (23) to the second end (24), including a second end (24). The heat exchanger according to any one of claims 1 to 3, wherein the heat exchanger is characterized in that. Each channel (26) comprises a first opening (26a) and a second opening (26b) located at the first and second ends (23, 24), respectively, and at least one first opening (26b). 26a) has a different fluid passage than the fluid passage of another first opening (26a), and / or at least one second opening (26b) is another second opening (26b). 26b) The heat exchanger according to claim 4, wherein the heat exchanger has a fluid passage portion different from that of the fluid passage portion of 26b). The first opening (26a) and / or the second opening (26b) of the same channel (26) is a fluid passage portion that becomes larger as the flow path defined by the channel (26) becomes longer. The heat exchanger according to claim 5, wherein the heat exchanger has. The invention according to any one of claims 1 to 6, wherein the one or more channels (26) include means (28) for correcting the linear flow resistance of the channel (26). Heat exchanger. The heat exchanger according to claim 7, wherein the means (28) includes the shape of an internal profile of the channel (26). The heat exchanger according to claim 7 or 8, wherein the means (28) includes a partition wall (28) arranged in the channel (26). The heat exchanger according to any one of claims 7 to 9, wherein the means (28) includes a porous structure arranged in the channel (26), for example, a metal foam. The heat exchanger according to any one of claims 1 to 10, wherein the dividing wall (25) has a linear profile in a vertical cross section. The heat exchanger according to any one of claims 1 to 10, wherein the dividing wall (25) has a predetermined curved profile in a vertical cross section. The heat exchanger of claim 12, wherein the predetermined curve profile comprises at least one inflection point (P). The dispersion element (22) extends along the length (L1) in the longitudinal direction (z) and over the width (L2) in the lateral direction (y), and is between the length (L1) and the width (L2). The heat exchanger according to any one of claims 1 to 13, wherein the ratio of the heat exchanger is less than 20%, preferably 5 to 10%. The heat exchanger according to any one of claims 1 to 14, wherein the dispersion element (22) extends along a length (L1) of less than 500 mm, preferably 50 to 200 mm. The dispersion element (22) has a height of at least 2 mm, preferably at least 5 mm, preferably 2 to 15 mm, measured in the vertical direction (x) perpendicular to the plate (2). The heat exchanger according to any one of claims 1 to 15, characterized in that. The heat exchanger according to any one of claims 1 to 16, wherein the dispersion element (22) is preferably a monolithic element manufactured by an additional manufacturing method or casting.

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