JP2013542394A - Perforated fins for heat exchangers - Google Patents

Abstract

The plate fin heat exchanger comprises a folded fin plate comprising fins, the fin plate comprising a plurality of perforations, the plurality of perforations being on the fin plate when the fin plate is in the deployed state. Positioned in parallel rows, such parallel perforation rows on the fin plate have a first spacing (S1) between the parallel perforation rows, a second between successive perforations in each of the parallel perforation rows. A spacing (S2), a third spacing (i.e. offset) between perforations in each adjacent parallel perforation row (S3), and a perforation diameter (D); The ratio of one interval (S1 / D) is in the range of 0.75 to 2.0, and the angle between the fins and the parallel perforation row is 5 degrees or less (≦ 5 °).
[Selection] Figure 1

Description

  Plate fin heat exchangers are generally used to exchange heat between process streams for the purpose of heating, cooling, boiling, evaporating or condensing the process stream. Process conditions for these heat exchangers include single-phase or two-phase flow and heat transfer. Some plate fin exchangers include only two flows, while other exchangers include multiple flows in multiple groups of plate fin passages. Individual streams can be fed into and extracted from the heat exchanger, respectively, using nozzles and headers. Each flow flows into a specific plate fin passage assigned in the bank of adjacent plate fin passages. The individual plate fin passages are contained between a pair of partition plates separated by fins, and each plate fin passage is surrounded by side bars and end bars at the outer periphery so that they are isolated from each other And can contain the fluid of interest. When different temperature flows enter the plate fin passages adjacent to each other, they are the partition plates called primary heat transfer surfaces, as well as the fin legs separating them, the secondary Heat is exchanged through fin legs, referred to as static heat transfer surfaces.

  Plate fin exchangers can be formed by using many different types of fins, such as flat, perforated, serrated, and corrugated. One embodiment of the present invention deals with perforated fins that are employed in the industry, but in an inefficient manner. Although plate fin heat exchangers with perforated fins according to the present invention have particular application in low temperature processes such as air separation, these plate fin heat exchangers can also be used in other heat transfer processes.

  When a flow or fluid enters the channel of the plate fin heat exchanger, it exhibits a large heat transfer rate due to the known inlet effect. After the inlet effect, the flow or fluid immediately reaches a steady state due to the very small heat transfer coefficient. In particular, if the flow is characterized as being in a turbulent state or in a transition state between a laminar and turbulent state, all surfaces where fluid flows along the surface Adjacent to the laminar and viscous boundary layers are known to form. The overall effect is to reduce the average heat transfer coefficient in such exchangers. The low heat transfer rate condition can be at least partially nullified by periodically interrupting this boundary layer, for example, by various means such as introducing perforations or saw teeth in each fin. The introduction of perforations or serrations in each fin increases the heat transfer performance, but such introduction also increases the pressure loss, so to achieve superior performance, the perforations or serrations in each fin Geometric shape and configuration are important. That is particularly important in the case of perforated fins, because they interrupt the flow and lead to an increase in the local heat transfer coefficient in the vicinity of the perforations, but the introduction of perforations in each fin is also Because it also results in a loss of surface area from the original material that would otherwise have been useful for overall heat transfer from the heat exchanger. Similarly, removing metal in the form of perforations, for example, can significantly reduce the strength of the remaining material. Therefore, the problem of improving the performance of plate fin heat exchangers by using perforated fins is complex and excellent performance is achieved by systematizing the geometry and arrangement for using such perforations. It is important to achieve.

  Historically, publications on plate fin heat exchangers have provided a general description of the overall geometry and basic methods for the manufacture of plate fin exchangers. These publications discuss many components of plate fin heat exchangers, their relationship to one another, and the manner in which they are assembled and brazed together, There is a short description of perforated fins that can be utilized in such plate fin heat exchangers. Even if some nominal details are disclosed, each publication does not discuss any suitable geometries and patterns for use.

  For example, Shozo Hotta of Sumitomo Precision Industries, Ltd. (SPP) was held at the Cliff Lodge Conference Hall in Snowville, Utah, June 22-27, 1997, and edited by R.K. “Aluminum Brazed Plate Fin Heat Exchangers for Process Industries”, a chapter on compact heat exchangers for the process industry, “Aluminum Brazed Plate Fin Heat Exchangers for Process Industries” , "a chapter of Compact Heat Exchangers for the Process Industries, edited by RK Shah, proceedings of the International Conference for the Process Industries, held at Cliff Lodge and Conference Center, Snowbird, Utah, June 22-27, 1997, by Shozo Hotta from Sumitomo Precision Products (SPP)), an overview of plate fin heat exchangers by Sumitomo Precision Industries (SPP), a leading supplier of plate fin heat exchangers. Description is disclosed. In particular, FIG. 4 on page 181 of such document provides photographic evidence of a general fin type including perforated fins. As described and taught therein, a perforated fin is a regular plate with a small round hole or perforation that is constant with respect to the long axis of each perforation on the flat plate. It is formed by bending at a large angle. However, no further details are presented.

  This manufacturing method is very common in the industry to minimize overall costs. A few types of standard perforated plate materials can be used to make a wide range of finished fins with various dimensions. However, this type of manufacturing method for perforated fins leads to irregular placement of perforations on the fins, resulting in poor performance of the perforated fins.

  US Pat. No. 6,834,515 B2, to Thunder et al., Referred to as “plate fin heat exchanger with textured surface,” also discloses various perforated fins. The Thunder patent teaches the use of surface textures to enhance the performance of other perforated fins. FIG. 2B of the Thunder patent illustrates exemplary fins with rows of perforations along the top and sides of the fins, where each perforation is aligned laterally. Embodiment 1 of the Thunder patent states that the perforated fin has about 10% open area. However, no other details are provided regarding the perforations.

  U.S. Pat. No. 5,603,376 to Hendricks, referred to as “Heat Exchanger for Electronic Cabinets”, describes heat for passive heat exchange between a weatherproof sealed electronic cabinet and the external environment. Describes an exchange. FIG. 2 of the Hendricks patent shows a heat generating side fin 21 with perforations 25 contained therein. The Hendricks patent teaches that each fin 21 is formed by forming or folding a perforated plate material in a bowl shape. Each perforation is said to be orthogonal to the direction of the fold. FIG. 2 of the Hendricks patent shows that each perforation is a single row of perforations along the sides of the fins 21, but in the lower side where the corrugated troughs or crests are formed, the perforations are Nothing is shown. Furthermore, the Hendricks patent does not provide any teaching regarding the location of each perforation.

  Y. Zhu and Y. Magazine "Heat Transfer" by Lee, November 2008, Vol. 130, 111801-1-8, Y. Zhu and Y. “Three-dimensional numerical simulation on the laminar flow and heat transfer in four basic fins of plate-fin heat exchangers”, by Y. Zhu and Y. Li, Journal of Heat Transfer, November 2008, vol. 130, 111801-1 to 8, four samples (flat, perforated, strip offset (other terms for sawtooth) ), And calculations based on computational fluid dynamics (CFD) performed on the performance of each fin that is wavy) The document of Du and Lee describes the first appearance of a compact heat exchanger. Following the enumeration of many major publications revealed from “To the best of the author's knowledge, there is insufficient attention received in the literature for complete three-dimensional flow and heat transfer in perforated fins.” It has said.

  Such a description is important and supports and results in Applicants' conclusion, i.e., less than optimally known in the field of perforated fins.

  As part of the comparison of the four fins above, the authors of Ju and Lee performed a CFD calculation on the geometry of one particular exemplary perforated fin. In order to reasonably maintain the size and time of the operation, the author included only the minimal repeating structure shown in FIGS. 2a and 2b on page 2 of the document. The cross-section modeled for the perforated fin represents half the wavelength of one fin, which includes each half of the top and bottom fin lengths and one complete fin height. . On the other hand, these include a series of half perforations at the top and bottom and a series of complete perforations at the fin height, all along the flow length. Similarly, the complete structure shown in FIG. 1D is exactly one row of perforations along the top, bottom and sides of each fin channel along the flow length, all of which are aligned laterally. It corresponds to the drilling of. The diameter of each perforation is 0.8 mm as shown in Table 1, and the spacing of each perforation along the fins appears to be about 1.4 mm between the centers, as can be estimated from FIGS. 6C and 7C. This frequency of drilling presents approximately 16% open area only on the sides of the plate fin passage (i.e., the magazines of Ju and Lee count or count the drill holes at the top or bottom of the fin to determine the open area. This is not considered because fin perforations at the top and bottom of the fin are covered by a divider plate). The method for determining this open area is shown in Table 1 below the specification column. Such a pattern achieves approximately 20% open area in a flat perforated plate prior to being formed into fins. This geometry is likely to represent the general case chosen by the author to model what he considers suitable with respect to drilling patterns and geometry without any indication or teaching. It is.

  Thus, one particular exemplary perforated fin geometry described above is simply the above to compare against the above four fins (flat, perforated, strip offset, and wavy forms). It is just a typical perforated fin used by the author. The patterns and geometric shapes modeled by the author are different from those taught based on this application.

  In summary, the prior art description of perforated fins is short in details regarding the geometry of the perforated fins used in plate fin exchangers. Also, even if a geometric aspect such as an open area is cited, each perforation is positioned so that the overall capital and operating costs of the plate fin heat exchanger can be minimized or There is no teaching on how to select the optimal geometry for each perforation to achieve optimal performance.

  It is desirable to increase the efficiency and performance of plate fin heat exchangers.

  Furthermore, in order to improve the heat transfer efficiency, it is desirable to improve the turbulent flow characteristics of the single phase flow in the plate fin passage of the plate fin exchanger.

  In addition, it is desirable to provide a plate fin exchanger that exhibits high performance characteristics for low temperature applications such as those used in air separation and for other heat transfer applications.

  In addition, it is desirable to achieve a more efficient air separation process that utilizes a plate fin exchanger that is more compact and / or more efficient than previously disclosed.

  Furthermore, a plate fin exchanger design that minimizes at least one of the size, weight and cost of the heat exchanger, which is more efficient and / or the unit of product produced It would be desirable to realize a design aspect that results in an air separation process that has a lower cost per volume.

  Furthermore, a plate fin heat exchanger that uses fins with perforation patterns and geometries that give better performance than previously disclosed fins, and that overcomes the disadvantages of the fins disclosed so far. It would also be desirable to implement a method for assembling a plate fin heat exchanger that would overcome and provide better and more useful results.

  The disclosed embodiments provide a new pattern of fin perforations and new geometries used in plate fin heat exchangers to achieve overall heat transfer performance within the allowed pressure drop constraints. Satisfying the demands of the industry by maximizing. Compared to the fin patterns and geometries disclosed so far, the advantages of such new patterns and geometries of fin drilling include the overall capital and operating costs of the heat exchanger system. (1) a substantial decrease in volume; (2) a substantial increase in heat transfer efficiency; so that the capital and operating costs of processes utilizing such heat exchanger systems are also reduced. 3) a considerable reduction in pressure drop loss; or (4) a certain sensible combination of factors (1) to (3).

  Although the disclosed embodiments included herein primarily contemplate easyway fins in which the flow is substantially parallel to the fin flow channel, the teachings provide a constant heat transfer. It may also be applicable to distribution fins that perform functions simultaneously, where the flow is predominantly parallel to the fin flow channel, rather than exclusively. Embodiments disclosed herein may include, for example, flow length within a plate fin passage of a plate fin exchanger that includes a fin channel with the perforation patterns and geometries disclosed herein. Especially suitable for applications where the fluid flow encounters heat transfer over at least 80%, more preferably over at least 90% of the flow length, most preferably over 100% of the flow length, without any phase change ing.

In the first embodiment, a folded fin plate including fins having a predetermined height, a predetermined width, and a predetermined length, and is positioned between the first partition plate and the second partition plate. A folded fin plate,
A first side bar and a second side bar, wherein the first side bar is between the first partition plate and the second partition plate and adjacent to the first side portion of the bent fin plate And the second side bar is positioned between the first partition plate and the second partition plate and adjacent to the second side portion of the folded fin plate, A first side bar and a second side bar that form at least part of the plate fin passage;
A plate fin heat exchanger comprising:
The fin plate includes a plurality of perforations,
The plurality of such perforations are positioned in parallel rows on the fin plate when the fin plate is in the deployed state,
Such parallel perforation rows on the fin plate are adjacent by a first spacing (S1) between the parallel perforation rows, a second spacing (S2) between sequential perforations in each of the parallel perforation rows. A third interval (ie offset) between perforations in each parallel perforation row (S3) and a perforation diameter (D);
The ratio (S1 / D) of the first spacing between the parallel perforation rows to the perforation diameter is in the range of 0.75 to 2.0; and
A plate fin heat exchanger is disclosed wherein the angle between each fin and the parallel perforation row is 5 degrees or less (≦ 5 °).

In the second embodiment, the plate fin heat exchanger according to the first embodiment is a process of exchanging heat between at least two flows,
At least one flow is subject to heat transfer without phase change over at least 80% of the length of the plate fin passage; and
A process is disclosed in which the Reynolds number of the at least one stream is in the range of 800 to 100,000, more preferably in the range of 1,000 to 10,000.

In the third embodiment, using the plate fin heat exchanger according to the first embodiment, a process of separating nitrogen, oxygen and / or argon from air by low-temperature distillation,
At least one flow over at least 80% of the length of the plate fin passage, more preferably over at least 90% of the length of the plate fin passage, most preferably over 100% of the plate fin passage. A process is disclosed that is left to heat transfer without change.

In the fourth embodiment,
A method of manufacturing a plate fin heat exchanger, comprising:
Providing at least one perforated plate, the at least one perforated plate comprising a plurality of perforations arranged in parallel rows, wherein the parallel perforated rows on the perforated plates Is a first interval (S1) between the parallel perforation rows, a second interval (S2) between sequential perforations in each of the parallel perforation rows, and a third interval between perforations in each adjacent parallel perforation row. The ratio (S1 / D) of the first spacing between the parallel drilling rows to the drilling diameter has a spacing (ie offset) (S3) and a drilling diameter (D) in the range of 0.75 to 2.0. There is a stage,
Folding the at least one perforated plate to form a bent perforated plate so that the angle between each fin and the parallel perforated row is 5 degrees or less (≦ 5 °); ,
A first side bar adjacent to the first side of the at least one folded perforated plate; a second side bar adjacent to the second side of the at least one perforated plate folded; A first distributor fin adjacent to the first end of the at least one folded perforated plate and a second distributor adjacent to the second end of the at least one perforated plate. Positioning the first end bar adjacent to the first distributor fin and the second end bar adjacent to the second distributor fin to provide a preliminary plate fin passage; Forming, and
Placing the preliminary plate fin passage of step (c) between the first and second partition plates to form a plate fin passage therebetween; and
Combining the plate fin passage of step (d) with other plate fin passages to form a plate fin heat exchanger;
Brazing the plate fin heat exchanger;
A method is disclosed.

  The foregoing general description, as well as the following detailed description of preferred embodiments, is better understood when read in conjunction with the accompanying drawings. For the purpose of illustrating the embodiments, example configurations are shown in the figures, but the invention is not limited to the specific methods and apparatus disclosed.

1 is an exploded perspective view of a basic element or subassembly of a plate fin heat exchanger with fins having perforation patterns and geometries according to one embodiment of the present invention. FIG. FIG. 6 is a schematic diagram illustrating an embodiment of a drilling pattern on a planarizing plate before being shaped into fins, in accordance with the present invention. Figure 5 is a graph showing the relative heat transfer and pressure loss performance of a perforated fin as a function of S1 / D, with a preferred range representation.

  One embodiment of the present invention relates to a plate fin exchanger comprising perforated fins in at least a portion of a plate fin passage and a method for assembling such a plate fin exchanger. The perforated fin is assembled using a flat perforated plate. The formed fin has a specific relationship with the perforation pattern on the flat plate. Some plate fin passages have each fin described above, while other plate fin passages may have different types of fins, such as flat, perforated, strip offset, and wavy forms, for example. A plate fin heat exchanger with such perforated fins has particular application to low temperature processes such as air separation, but it can also be used in other heat transfer processes.

  Referring to FIG. 1, the plate fin heat exchanger of the present invention comprises several plate fin passages, some of which are partition plates or plates 30, 40, side bars 50, 60 (not shown). At least one fin plate 10 is intermediate between the distribution fin (which is generally known in the art, but generally known in the art). Created by placing. These plate fin passages comprise a specific pattern of perforations 20 in at least some parts of such plate fin passages.

  Prior to being formed into a fin plate 10 as shown in FIG. 1, the fin plate 10 may be aluminum, copper, another alloy, or any other heat known in the art for making fins. A flat plate made of a conductive material. As shown in FIG. 2, the flat fin plate 10 includes perforations 20. The flat plate has a special perforation pattern comprising several parallel perforation rows 100, 200, 300, each parallel row 100, 200, 300 being a perforation 1A, 1B, 1C; 2A, 2B, respectively. , 2C; and 3A, 3B, 3C. In one embodiment, in each row of perforations 1A, 1B, 1C; 2A, 2B, 2C; and 3A, 3B, 3C, the flat plate is folded to form a fin plate 10 as shown in FIG. Sometimes aligned in a direction parallel to the desired direction of each fin. When each fin is employed as a weak resistance fin, the nominal flow line of the flow is parallel to the direction of each perforation, as shown in FIG.

  As shown in FIG. 2, each perforation has a diameter (D). The spacing between parallel perforation rows 100, 200, 300 is represented as S1, while the spacing between sequential perforations in the flow direction (ie perforations 2A and 2B) is represented as S2. The offset between perforations (ie, between 2A and 3A) in adjacent parallel rows 100, 200, 300 is denoted as S3.

In one embodiment, Applicants have found that plate fin heat exchangers have higher efficiency compared to conventional heat exchangers that are not designed accordingly when the following parameters are each kept within the following ranges: And the amazing results of improving performance:
(1) perforation diameter D in the range of 1 mm to 4 mm;
(2) open area in the range of 5% to 25%;
(3) a ratio S3 / S2 within the range of 0.25 to 0.75; and
(4) Ratio S1 / D within the range of 0.75 to 2.0, most preferably within the range of 0.75 to 1.0.

  In the most preferred arrangement / embodiment, the fluid flow direction is parallel to the parallel perforation rows 100, 200, 300, but in the preferred arrangement / embodiment, the fluid flow direction is parallel perforation row 100. , 200 and 300 directions, within 5 degrees (5%). This means that as each fin is formed, the fin plate 10 should be folded so that the angle between the fin fold and such parallel perforation rows 100, 200, 300 is no more than 5 °, The most preferred arrangement means that such an angle is zero degrees (0 °).

  The fin plate 10 may include perforations 20 that are circular as shown in FIGS. 1 and 2, but are not limited to those skilled in the art, and are not limited to oval shapes, rectangular shapes, parallelogram shapes, and It will be understood that non-circular perforations, such as other such shapes, may also be used.

  In yet another embodiment, the arrangement of offset perforated rows is repeated every two rows as shown in FIG. 2 (ie, row 100 is row 300, (not shown) 500, (not shown). (Offset is the same as 700). In addition, when a flat perforated plate is folded into fins in the fin forming operation to form each fin, the structure of each perforation that results on the finished fin plate 10 is how the material flows in the fin forming mold. Because of these mechanical details, it is easy to have complex relationships. In one embodiment, the flat plate is more preferably a plate in which the perforation pattern on the finished fin plate 10 is at least fifty percent (50%) of the plate fin passage of the heat exchanger that includes such perforated fins. At least once every ten (10) fin wavelengths, more preferably at least eighty percent (80%) of the fin passages, and most preferably one hundred percent (100%) of the plate fin passages, It is folded so that it is repeated at least once every five (5) fin wavelengths.

  In a further embodiment, the perforated plate, as taught by U.S. Pat. No. 5,637,097, incorporated herein by reference in its entirety, prior to the material being folded into fins, A surface texture can be applied. Alternatively, the surface texture can be created in the process of creating fins from a flat perforated plate.

The embodiments described herein are suitable for plate fin heat exchangers, where at least a portion of each fin is in the range of 0.25 inches to 1 inch (.635 centimeters to 2.54 centimeters). More preferably in the range of 0.40 inch to 0.75 inch (1.016 cm to 1.905 cm), and most preferably in the range of 0.5 inch to 0.6 inch (1.27 cm to 1.524 cm). Each embodiment is preferably applied when the fluid flow condition in such a plate fin passage is in a transition state between a laminar flow state and a turbulent flow state, or in a turbulent flow state. This can be expressed as a Reynolds number range of 800-100,000, more preferably 1,000-10,000. The Reynolds number is calculated as follows:
Re = ρVD / μ
Where
Re = Reynolds number,
ρ = fluid density,
V = fluid velocity,
μ = fluid viscosity,
D = 4A / P,
A = cross-sectional area of fluid flow, and
P = the entire circumference of the fluid flow.
For plate fin passages, it is common to calculate the fluid diameter D based on the individual plate fin passages, and the calculation of the present application is to calculate A (fluid flow cross-sectional area) and P (fluid flow cross section). Based on the use of basic sheet metal without adjusting them for the contribution of each perforation to the entire circumference).

  Embodiments of the present invention have considerable value because the plate fin heat exchanger is made more compact compared to a conventional plate fin exchanger, such as an air separation plant. This is because the sum of factory capital costs and operating costs can be saved.

Embodiment 1
In order to better understand the effect of perforations on the fin geometry, several sample problems were solved using computational fluid dynamics (CFD). In using this technique, it is common to limit the computation to a certain repetitive structure in order to limit the computational scale of the problem. However, when trying to quantify the effects of a particular perforation pattern, the overall geometry of the heat exchanger is very important even when limiting the problem to a single subchannel in the plate fin passage. It is complicated. For this reason, another form of approximation was used.

  In most plate fin exchangers, the secondary surface area tends to be a dominant percentage of the total area. As previously mentioned, this is the area represented by each fin leg that spans and separates the dividers or plates 30, 40 representing the primary surface area. To understand the effect of positioning each hole, a typical periodic region of two infinitely parallel plates is modeled so that heat transfer and pressure loss occur when air flows between them. Was quantified. A schematic configuration of each perforation on a flat plate is shown in FIG.

  Embodiment 1 relates to a weak resistance fin used for heat transfer and / or distribution, in which case the flow direction is generally relative to the fin direction as shown in FIG. Parallel.

  Using CFD, many exemplary cases were solved where the various spacings (S1, S2, S3) were changed while keeping the diameter (D) and overall open area of each perforation constant. . Specifically, the intervals S1 and S2 were changed simultaneously, while the offset S3 was set equal to 1/2 of the interval S2. In these exemplary cases, there is only one independent parameter and the results are listed in Table 1 and shown in FIG.

  The exemplary calculations above show the relative values of pressure loss and heat transfer rate obtained by simply changing the perforation pattern. The exemplary data was plotted after scaling for each value that occurred when the ratio of spacing to perforation size was about 3. As this ratio is reduced to about 2, there is a considerable improvement in heat transfer. As recognized in Table 1, the heat transfer increase is greater than the corresponding increase in pressure loss. Thus, a heat exchanger designed with a ratio of 2 can be shortened by a factor of about 1.2 compared to a heat exchanger designed with a ratio of 3, while the overall pressure loss is even lower. This is a considerable decrease in length and hence in volume. If the ratio is reduced to less than 2, the improvement continues and a particularly good value is realized for ratio values between 0.75 and 1. In this ratio range, there is an improvement of about 1.25 in terms of heat transfer. The required length or volume is the reciprocal of this ratio, ie 0.80 or 80 percent (80%). This represents a substantial size reduction of only 20 percent (20%), while the pressure drop is also reduced by a ratio of 1.18 / 1.25, which is equal to 0.94 or 94 percent (94%) . Thus, there can be a 20 percent (20%) reduction in length or volume, while there is also a 6 percent (6%) reduction in pressure drop.

  These are significant improvements that can be realized by arranging the drilling locations as disclosed herein and have not been known or disclosed before. Indeed, some explicit disclosure, either explicitly described, implied or illustrated, teaches that such an arrangement is contrary to such an arrangement. As shown in FIG. 3, a ratio range of 0.75 to 2.0 is preferred, and a range of 0.75 to 1.0 is particularly preferred.

Embodiment 2
Embodiment 2 illustrates an exemplary improvement realized using the teachings contained herein. As previously mentioned, the conventional teaching regarding perforated fins in plate fin heat exchangers did not discuss suitable geometries or perforation patterns as outlined herein. However, CFD literature by Non-Patent Document 2 such as Ju cited above considered the effect of specific perforated fins compared to other forms of fins such as flat, serrated and wavy fins. . This example was created by applying the drilling pattern used in the CFD literature by Ju et al. In the same manner as described in Embodiment 1.

  The parameters of the drilling pattern on the flat plate before being folded into fins are as follows: drilling diameter (D) = 0.8 mm; open area = 20%; S1 = 1.81 mm; S2 = 1.39 mm And S3 = 0. The calculated relative performance for heat exchangers utilizing such prior art fins is shown in Table 2.

  As shown in Table 2, the relative heat transfer coefficient and the relative pressure gradient of the preferred embodiment disclosed herein is 26% greater than the heat exchanger of the above CFD literature, so both heat exchangers A heat exchanger constructed according to the teachings of the preferred embodiment disclosed herein as having an equal or matching heat transfer duty and pressure drop is a heat exchanger constructed according to the teachings of the CFD literature. A smaller relative length (shorter by 21%) and a smaller relative volume (smaller by 21%) can be achieved compared to. This is a considerable advantage for utilizing fins made in accordance with the teachings of the preferred embodiments disclosed herein as compared to the teachings of the CFD literature described above.

  While aspects of the present invention have been described with reference to preferred embodiments in the various figures, other similar embodiments can be used to accomplish the same functions as the present invention without departing from the invention? Or it should be understood that modifications and additions may be made to the described embodiments. For example, the following aspects should also be understood as part of the present disclosure:

Aspect 1.
A folded fin plate having fins having a predetermined height, a predetermined width, and a predetermined length, the bent fin plate being positioned between the first partition plate and the second partition plate; ,
A first side bar and a second side bar, wherein the first side bar is between the first partition plate and the second partition plate and adjacent to the first side portion of the bent fin plate And the second side bar is positioned between the first partition plate and the second partition plate and adjacent to the second side portion of the folded fin plate, A first side bar and a second side bar that form at least part of the plate fin passage;
A plate fin heat exchanger comprising:
The fin plate includes a plurality of perforations,
The plurality of such perforations are positioned in parallel rows on the fin plate when the fin plate is in the deployed state,
Such parallel perforation rows on the fin plate are adjacent by a first spacing (S1) between the parallel perforation rows, a second spacing (S2) between sequential perforations in each of the parallel perforation rows. A third interval (ie offset) between perforations in each parallel perforation row (S3) and a perforation diameter (D);
The ratio (S1 / D) of the first spacing between the parallel perforation rows to the perforation diameter is in the range of 0.75 to 2.0; and
The angle between each fin and the parallel perforation row is 5 degrees or less (≦ 5 °),
Plate fin heat exchanger.

Aspect 2.
The plate fin heat exchanger according to aspect 1, wherein the angle between each fin and the parallel perforated row is zero degrees (0 °).

Aspect 3.
A plate fin heat exchanger according to aspect 1 or aspect 2, wherein the ratio (S1 / D) of the first spacing between the parallel perforation rows to the perforation diameter is in the range of 0.75 to 1.0.

Aspect 4.
The ratio of the third interval (ie, offset) (S3) between perforations in each adjacent parallel perforation row to the second interval (S2) between sequential perforations in each of the parallel perforation rows is 0.25. The plate fin heat exchanger according to any one of aspects 1 to 3, wherein the plate fin heat exchanger is within a range of ˜0.75.

Aspect 5.
The plate fin heat exchanger according to any one of aspects 1 to 4, wherein 5% to 25% of the area of the bent fin plate is occupied by each perforation in the expanded state.

Aspect 6.
The plate fin heat exchanger according to any one of aspects 1 to 5, wherein the perforation diameter (D) is in the range of 1 mm to 4 mm.

Aspect 7.
The plate fin heat exchanger according to any one of aspects 1 to 6, wherein the perforations are circular.

Aspect 8.
The plate fin heat exchanger according to any one of aspects 1 to 6, wherein the perforations have an elliptical shape, a rectangular shape, or a parallelogram shape.

Aspect 9.
A plate fin according to any one of aspects 1 to 8, wherein the adjacent parallel perforation rows are offset in an interleaved fashion such that the position of the parallel perforation rows is repeated in a row of perforations. Heat exchanger.

Aspect 10.
The adjacent parallel row of perforations is at least 50% of the plate fin passage of the heat exchanger including the perforated fin, more preferably at least 80% of the plate fin passage, most preferably 100% of the plate fin passage. , Offset so that the position of the parallel perforation row on each fin of the folded fin plate is repeated at least once every 10 fin wavelengths, more preferably at least once every 5 fin wavelengths. A plate fin heat exchanger according to any one of aspects 1 to 8, wherein

Aspect 11.
The plate fin heat exchanger according to any one of aspects 1 to 10, wherein the bent fin plate has a surface texture.

Aspect 12.
Any of aspects 1 to 11, wherein the fin height is in the range of 0.25 inch to 1 inch, more preferably in the range of 0.4 inch to 0.75 inch, and most preferably in the range of 0.5 inch to 0.6 inch. A plate fin heat exchanger according to one embodiment.

Aspect 13.
The plate fin heat exchanger according to any one of aspects 1 to 12, wherein the bent fin plate is a heat transfer fin or a distribution fin having low resistance.

Aspect 14.
The plate fin passage is adapted to receive a fluid flow; and
From aspect 1, wherein the fluid flow is subject to heat transfer for at least 80% of the length of the plate fin passage, more preferably for at least 90%, and most preferably for 100% without phase change. The plate fin heat exchanger according to any one of aspects 13.

Aspect 15.
A process for exchanging heat between at least two streams in a plate fin heat exchanger configured according to any one of aspects 1 to 13, comprising:
At least one flow is subject to heat transfer without phase change over at least 80% of the length of the plate fin passage; and
A process wherein the Reynolds number of the at least one stream is in the range of 800 to 100,000, more preferably in the range of 1,000 to 10,000.

Aspect 16.
A process for separating nitrogen, oxygen and / or argon from air by low temperature distillation using the plate fin heat exchanger according to any one of aspects 1 to 13, comprising:
At least one flow over at least 80% of the length of the plate fin passage, more preferably over at least 90% of the length of the plate fin passage, most preferably over 100% of the plate fin passage. A process that is left to heat transfer without change.

Aspect 17.
A method of manufacturing a plate fin heat exchanger, comprising:
(A) deploying at least one perforated plate, wherein the at least one perforated plate comprises a plurality of perforations arranged in parallel rows, such parallel on the perforated plate; A perforated row includes a first interval (S1) between the parallel perforated rows, a second interval (S2) between sequential perforations in each of the parallel perforated rows, and a distance between perforations in each adjacent parallel perforated row. And a ratio (S1 / D) of the first spacing between the parallel drilling rows to the drilling diameter is 0.75 to 2.0. A stage that is within range,
(B) Folding the at least one perforated plate to form a bent perforated plate so that the angle between each fin and the parallel perforated row is 5 degrees or less (≦ 5 °) And the stage of
(C) a first side bar adjacent to the first side of the at least one folded perforated plate and a second side adjacent to the second side of the at least one folded perforated plate; A side bar is adjacent to the first end of the at least one folded perforated plate and a first distributor fin is adjacent to the second end of the at least one folded perforated plate. Preliminary plates with a second distributor fin positioned adjacent to the first distributor fin, a first end bar, and a second end bar adjacent to the second distributor fin Forming a fin passage;
(D) placing the preliminary plate fin passage of step (c) between the first partition plate and the second partition plate to form a plate fin passage therebetween;
(E) combining the plate fin passage of step (d) with other plate fin passages to form a plate fin heat exchanger;
(F) brazing the plate fin heat exchanger;
Method.

Aspect 18.
The plate fin heat exchanger according to aspect 17, further comprising applying a surface texture to the at least one perforated plate prior to folding the at least one perforated plate in the step (b). How to manufacture.

  Therefore, the claimed invention should not be limited to any single embodiment or aspect, but rather the scope and scope should be construed according to the claims that follow.

Claims (18)

A folded fin plate having fins having a predetermined height, a predetermined width, and a predetermined length, the bent fin plate being positioned between the first partition plate and the second partition plate; ,
A first side bar and a second side bar, wherein the first side bar is between the first partition plate and the second partition plate and adjacent to the first side portion of the bent fin plate The second side bar is positioned between the first partition plate and the second partition plate and adjacent to the second side portion of the folded fin plate, thereby providing plate fins. A first side bar and a second side bar that form at least a portion of the passage;
A plate fin heat exchanger comprising:
The fin plate comprises a plurality of perforations;
The plurality of perforations are positioned in parallel rows on the fin plate when the fin plate is in an unfolded state,
Such parallel perforation rows on the fin plate are adjacent by a first spacing (S1) between the parallel perforation rows, a second spacing (S2) between sequential perforations in each of the parallel perforation rows. A third interval (ie offset) between perforations in each parallel perforation row (S3) and a perforation diameter (D);
The ratio of the first spacing between the parallel drilling rows to the drilling diameter (S1 / D) is in the range of 0.75 to 2.0;
The angle between each fin and the parallel perforation row is 5 degrees or less (≦ 5 °),
Plate fin heat exchanger.   The plate fin heat exchanger of claim 1, wherein an angle between each fin and the parallel row of perforations is zero degrees (0 °).   2. The plate fin heat exchanger according to claim 1, wherein the ratio (S1 / D) of the first spacing between the parallel drilling rows to the drilling diameter is in the range of 0.75 to 1.0.   The ratio of the third interval (ie, offset) (S3) between perforations in each adjacent parallel perforation row to the second interval (S2) between sequential perforations in each of the parallel perforation rows is 0.25. The plate fin heat exchanger of claim 1, which is in a range of ˜0.75.   The plate fin heat exchanger of claim 1, wherein 5% to 25% of the area of the bent fin plate is occupied by each perforation in the deployed state.   The plate fin heat exchanger according to claim 1, wherein the perforation diameter (D) is in the range of 1 mm to 4 mm.   The plate fin heat exchanger of claim 1, wherein the perforations are circular.   The plate fin heat exchanger according to claim 1, wherein the perforations have an elliptical shape, a rectangular shape, or a parallelogram shape.   The plate fin heat exchanger of claim 1, wherein the adjacent parallel perforation rows are offset in an interleaved manner such that the position of the parallel perforation rows is repeated in a row of perforations.   The adjacent parallel perforation rows are at least 50% of the plate fin passage of the heat exchanger including the perforated fin, more preferably at least 80% of the plate fin passage, most preferably 100% of the plate fin passage. Offset such that the position of the parallel perforation rows on each fin of the folded fin plate is repeated at least once every 10 fin wavelengths, more preferably at least once every 5 fin wavelengths. The plate fin heat exchanger according to claim 1.   The plate fin heat exchanger of claim 1, wherein the folded fin plate has a surface texture.   The fin height is in the range of 0.635 cm to 2.54 cm (0.25 inch to 1 inch), more preferably in the range of 1.016 cm to 1.905 cm (0.4 inch to 0.75 inch), most preferably 1.27 cm to 1.524. The plate fin heat exchanger of claim 1, wherein the plate fin heat exchanger is within a range of cm (0.5 inch to 0.6 inch).   The plate fin heat exchanger according to claim 1, wherein the bent fin plate is a heat transfer fin or a distribution fin having low resistance. The plate fin passage is adapted to receive a fluid flow;
2. The fluid flow is subject to heat transfer over a length of at least 80%, more preferably at least 90%, and most preferably 100% of the length of the plate fin passage, without phase change. Plate fin heat exchanger. A process for exchanging heat between at least two streams in a plate fin heat exchanger configured according to claim 1 comprising:
At least one flow is left to heat transfer without phase change over at least 80% of the length of the plate fin passage;
A process wherein the Reynolds number of the at least one stream is in the range of 800 to 100,000, more preferably in the range of 1,000 to 10,000. A process for separating at least one of nitrogen, oxygen and argon from air by low temperature distillation using the plate fin heat exchanger according to claim 1,
At least one flow over at least 80% of the length of the plate fin passage, more preferably over at least 90% of the length of the plate fin passage, most preferably over 100% of the plate fin passage. A process that is left to heat transfer without change. A method of manufacturing a plate fin heat exchanger, comprising:
(A) deploying at least one perforated plate, wherein the at least one perforated plate comprises a plurality of perforations arranged in parallel rows, such parallel on the perforated plate; A perforated row includes a first interval (S1) between the parallel perforated rows, a second interval (S2) between sequential perforations in each of the parallel perforated rows, and a distance between perforations in each adjacent parallel perforated row. And a ratio (S1 / D) of the first spacing between the parallel drilling rows to the drilling diameter is between 0.75 and 2.0. A stage that is within range,
(B) Folding the at least one perforated plate to form a bent perforated plate so that the angle between each fin and the parallel perforated row is 5 degrees or less (≦ 5 °) And the stage of
(C) a first side bar adjacent to the first side of the at least one folded perforated plate and a second side adjacent to the second side of the at least one perforated plate; A side bar is adjacent to the first end of the at least one folded perforated plate and a first distributor fin is adjacent to the second end of the at least one folded perforated plate. Preliminary plates with a second distributor fin, a first end bar adjacent to the first distributor fin, and a second end bar positioned adjacent to the second distributor fin Forming a fin passage;
(D) placing the preliminary plate fin passage of step (c) between a first partition plate and a second partition plate to form a plate fin passage therebetween;
(E) combining the plate fin passage of step (d) with other plate fin passages to form a plate fin heat exchanger;
(F) brazing the plate fin heat exchanger;
Method.   18. The plate fin heat exchange of claim 17, further comprising applying a surface texture to the at least one perforated plate prior to folding the at least one perforated plate in the step (b). A method of manufacturing a vessel.

Images