TWI463104B - Heat exchanger perforated fins - Google Patents

Description

Heat exchanger through hole fin

The present invention is directed to a plate fin heat exchanger comprising finned fins.

Plate fin heat exchangers are generally used for the purpose of exchanging heat between program streams for heating, cooling, boiling, vaporizing or coagulating such process streams. Processing conditions in these heat exchangers may involve single or two phase flow and heat transfer. Although some plate fin exchangers contain only two streams, other groups of plate fin channels contain multiple streams. Individual streams can be fed and withdrawn from the heat exchanger using nozzles and heads. Each stream inflow is distributed among designated plate fin channels in adjacent plate fin channel groups. The individual finned passages are mounted between a pair of dividing sheets, the fins are separated by the fins and the finned passages are surrounded by side bars and end bars On the outer surface, the finned channels can be isolated from each other and can be filled with fluid of interest. When the streams flow in mutually adjacent plate fin passages at different temperatures, the streams exchange heat through a separator called a primary heat transfer surface and a fin leg that separates the separators. These fin feet are referred to as auxiliary heat transfer surfaces.

Plate fin exchangers can be formed by using many different types of fins such as flat, perforated, serrated, and wavy. One embodiment of the present invention addresses perforated fins that are already in use in the industry, but are used in an inefficient manner. According to the present invention, plate fin heat exchangers having perforated fins have particular applications in cryogenic processes such as air separation, but these plate fin heat exchangers can also be used in other heat transfer procedures.

The plate fin heat exchanger passage exhibits a high heat transfer coefficient due to the well-known inlet effect when the stream or fluid enters the plate fin heat exchanger passage. After the post-inlet effect, the stream or fluid will quickly reach a steady state condition with a much lower heat transfer coefficient. Particularly when the flow is characterized by disturbance dynamics or a transitional state between laminar flow and disturbance dynamics, it is known that the laminar flow and the viscous boundary layer will be formed adjacent to all surfaces through which the fluid flows. The overall effect is to reduce the average heat transfer coefficient in this exchanger. The lower heat transfer coefficient condition can be at least partially reversed by a variety of means such as, for example, the introduction of perforations or serrations in the fins to periodically disturb the boundary layer. The introduction of perforations or zigzag protrusions in the fins will improve the heat transfer performance, but this introduction also increases the pressure loss and, therefore, the geometry and arrangement of the perforations or zigzag protrusions in the fins is very good for achieving improved performance. important. It is particularly important in the case of perforated fins, because when it disturbs the flow and causes a local heat transfer coefficient at the proximal end of the perforations, the introduction of perforations in the fins also causes loss of surface area of the original material, otherwise it will It is beneficial to the overall heat transfer of the heat exchanger. In addition, for example, removing the metal by perforation greatly reduces the strength of the remaining material. Therefore, the problem of improving the performance of the plate fin heat exchanger by using perforated fins is complicated and it is particularly important to arrange the geometry and arrangement of such perforations to achieve improved performance.

Historically, publications on plate fin heat exchangers provide a general description of the overall geometry and basic methods for the manufacture of plate fin heat exchangers. Although these publications discuss many of the constituent parts of a plate fin heat exchanger, their relationship to each other, and how they are assembled and brazed together, these publications have a brief reference to the perforated fins that can be applied to such plate fin heat exchangers. description. Even in cases where some symbolic details were revealed, the publications did not discuss the use of any preferred geometry and patterns.

For example, in the chapter "Aluminum Brazed Plate Fin Heat Exchangers for Process Industries," Compact Heat Exchangers for the Process Industries, edited by RK Shah, agenda of the International Conference for the Process Industries, June 22-27, 1997 Day, held at the Cliff Lodge and Conference Center in Tobacco Island, Utah, published by Shozo Hotta of Sumitomo Precision Products (SPP), a plate fin heat exchanger manufactured by SPP, a major supplier of such heat exchangers The general description of this is revealed. In particular, Figure 4 on page 181 of this reference provides a photo demonstration of a common fin type including perforated fins. As described and taught therein, the perforated fin systems are formed by folding a small circular opening with regular penetration or a perforated plate that is somewhat larger than the major axis of the perforation on the flat sheet. However, no further details were presented.

This manufacturing method is very common in the industry to minimize overall cost. Some standard perforated sheets can be used to make a wide range of finished fins with varying sizes. However, this type of perforated fin manufacturing method results in irregular placement of the perforations on the fins, resulting in insufficient performance of the perforated fins.

U.S. Patent No. 6,834,515 B2, entitled "Plate Fin Exchangers with Textured Surfaces," granted to Sunder et al., also discloses a variety of different perforated fins. The Sunder patent teaches the application of surface textures to enhance the performance of other perforated fins. Figure 2B of the Sunder patent illustrates an exemplary fin with a row of perforations along the top and sides of the fins, wherein the perforations are aligned from the sides. Example 1 of the Sunder patent describes that the perforated fins have an open area of about 10%. However, no other details are provided regarding such perforations.

U.S. Patent No. 5,603,376, entitled "Heat Exchanger for Electronics Cabinet," awarded to Hendrix, describes a heat exchanger for passive heat exchange between a sealed electronic device housing for weathering and the environment. Figure 2 of the Hendrix patent shows a heat generating side fin 21 containing a wearer 25 therein. The Hendrix patent teaches forming fins 21 by folding or folding a perforated sheet. The perforations are said to be perpendicular to the direction of the creases. Figure 2 of the Hendrix patent illustrates that the perforations are a single row of perforations along the sides of the fins 21, but no perforations are shown on the bottom side of the valleys or peaks that may form waves. Moreover, the Hendrix patent does not provide guidance on such perforated sites.

In "Three-dimensional numerical simulation on the laminar flow and heat transfer in four basic fins of plate-fin heat exchangers", edited by Y. Zhu and Y. Li, Journal of Heat Transfer, November 2008, Vol. 130, On pages 111801-1 through 8, there is a computational fluid dynamics (CFD) that reveals the performance of four specimens (flat, perforated, stripe offset (another serrated) and wave fins). Basic operations. The Zhu and Li papers list a number of important publications based on compression heat exchangers, which appear because they were first introduced and stated, "As far as the author is aware, the literature does not pay much attention to such perforations. Complete three-dimensional flow and heat transfer in the fins."

Such statements are obvious and seem to support and lead to the applicant's conclusions, in other words those known in the process for perforating fins are only sub-optimal.

Regarding the comparison of the four types of fins, the authors of the Zhu and Li papers perform CFD operations by specifying the exemplary perforated fin geometry. In order to keep the calculation size and time reasonable, the author only takes into account the minimum repeating structure illustrated in Figures 2a and 2b on page 2 of the paper. An exemplary cross-sectional view of the perforated fin represents half the wavelength of the fin, including half of each of the top and bottom fin lengths and a full fin height. These are then a series of semi-perforations on the top and bottom along the flow length and a series of full perforations at the height of the fin. The full structure, also illustrated in Figure 1D, corresponds to a row of perforations at the top, bottom and sides of each fin channel along the flow length, all aligned sideways. The diameters of the perforations are exemplified as 0.8 mm in Table 1 and the perforation spacing along the fins can be inferred from Figures 6C and 7C to appear approximately 1.4 mm from the center to the center. The frequency of this perforation indicates that there is only about 16% of the open area on the finned channels (i.e., the Zhu and Li papers do not calculate or take into account the perforations at the top or bottom of the fins in order to determine the open area. The top and bottom of the fins are covered by the dividers). The results of this opening measurement are exemplified in Table 1 under the specification column. Such a pattern can calculate approximately 20% of the open area on the flat perforated sheet prior to forming the flat perforated sheet. This geometry appears to represent a typical case where the author chooses to display without pointing out or teaching what they think may be better in terms of perforation patterns and geometric shapes.

Thus, the one of the specified exemplary perforated fin geometries described above is only representative perforated fins that the authors use to compare with the four types of fins (flat, perforated, stripe offset, and wave type). The styles and geometric shapes exhibited by the author are not the same as those taught by the present invention.

In summary, the previous description of perforated fins is an overview of the details of the perforated fin geometry used in the plate fin exchanger. Moreover, even if enumerating aspects of the geometry, such as the open area, there is no teaching of how to configure the perforations or how to best select the geometry that is best suited for the perforations for optimum performance in order to enable the fin heat exchangers. Total investment and operating costs are kept to a minimum.

We want to improve the efficiency of the plate fin heat exchanger and improve its performance.

In addition, in order to improve the heat transfer efficiency, we intend to improve the disturbance characteristics of the single-phase flow in the plate fin passage of the plate fin exchanger.

In addition, we have a plate fin exchanger that exhibits high performance characteristics for low temperature applications, such as users in air separation, and for other heat transfer applications.

Yet another desire is to have a more efficient air separation procedure that utilizes a plate fin exchanger that is denser and/or more efficient than previously disclosed.

In addition, we intend to have a plate fin exchanger design that minimizes the size, weight and/or cost of such heat exchangers, which will result in more efficient and/or less expensive products per unit volume. Air separation program.

In addition, what we would like to have is a method of assembling a plate fin heat exchanger that uses a fin with a perforated pattern and a geometry that provides better performance than the previously disclosed fins, and that overcomes the disadvantages of the previously disclosed fins. To provide better and more favorable results.

The disclosed embodiments meet the needs of this art by providing novel styles and novel geometries for fin perforations in plate fin heat exchangers to maximize overall heat transfer performance within a range of allowable pressure drops. The novel styles and novel geometries of this fin perforation outweigh the benefits of previously disclosed fin patterns and geometries including: (1) significant reduction in volume; (2) significant increase in heat transfer efficiency; (3) significant reduction in pressure drop losses Or (4) some sensible combinations of factors (1) through (3) such that the overall investment and operating costs of the heat exchanger system are reduced, thereby also reducing the capital and operating costs of the process utilizing the heat exchanger system.

Although the specific embodiments included herein are directed primarily to easyway fins in which most of the flow is parallel to the fin flow path, these teachings are also applicable to dispensing fins that simultaneously perform some heat transfer functions and flow therein. Main, but not complete, parallel to the fin flow path. The specific embodiments disclosed herein are particularly applicable to plate fins in which the fluid flow undergoes heat transfer without the finned exchanger (for example, a fin passage having a perforated pattern and geometry as disclosed herein). The application of phase change occurs in at least 80% of the flow length within the channel, more preferably in at least 90% of the flow length, and preferably in the 100% region of the flow length.

In a first embodiment, a plate fin heat exchanger is disclosed, comprising a folded fin, the folded fin comprising a fin having a height, a width and a length, the folded fin being configured in the first Between the separator and the second separator; and a first side rod and a second side rod, wherein the first side rod is disposed between the first partition sheet and the second partition sheet and adjacent to the folded fin a first side of the sheet, and wherein the second side rod is disposed between the first separator sheet and the second separator sheet and adjacent to the second side of the folded fin, thereby forming at least a portion of the plate fin passage; The fins comprise a plurality of perforations. When the fins are in a developed shape, the plurality of perforations are arranged in a plurality of parallel rows on the fins. The parallel rows of perforations on the fins are interposed between the parallel rows of perforations. a first spacing (S1), a second spacing (S2) between successive perforations in the parallel row of perforations, and a third spacing (or offset) between the perforations in adjacent parallel rows of perforations ( S3) and a perforation diameter (D), wherein the first between the parallel rows of perforations The ratio (S1 / D) of the bore diameter away from the tie lines between the angle range of 0.75 to 2.0, and wherein these parallel fins with such row of perforations is less than or equal to 5 degrees (= 5 °).

In a second embodiment, a method of exchanging heat between at least two streams in a plate fin heat exchanger according to the first embodiment is disclosed, wherein at least one stream is heat transferred without being in the board A phase change occurs in at least 80% of the length of the fin channel, and the Reynolds Number of the at least one stream is in the range of 800 to 100,000 and more preferably in the range of 1,000 to 10,000.

In a third embodiment, a method of separating nitrogen, oxygen and/or argon from air by cryogenic distillation is disclosed, which utilizes a plate fin heat exchanger according to the first embodiment, wherein at least one stream is subjected to heat Passing not in at least 80% of the length of the finned channels, more preferably in at least 90% of the length of the finned passages, and optimally in the length of the finned passages Phase changes occur in the 100% area.

In a fourth embodiment, a method of manufacturing a plate fin heat exchanger is disclosed, comprising the steps of: providing at least one perforated sheet, the at least one perforated sheet comprising a plurality of perforations arranged in a plurality of parallel rows, wherein the perforations are The parallel rows of perforations on the sheet comprise a first spacing (S1) between the parallel rows of perforations, a second spacing (S2) between successive perforations in the parallel rows of perforations, between adjacent parallel rows a third spacing (or offset) between the perforations in the perforations (S3) and a perforation diameter (D), wherein the ratio of the first spacing between the parallel rows of perforations to the perforation diameter (S1/D) Is in the range of 0.75 to 2.0; the at least one perforated sheet is folded into fins to form a folded perforated sheet such that the angle between the fins and the parallel rows of perforations is less than or equal to 5 degrees (= 5°); Positioning the first side bar adjacent to the first side of the at least one folded perforated sheet, the second side rod adjacent the second side of the at least one folded perforated sheet, the first dispensing fin being adjacent to the first end of the at least one folded perforated sheet a second distribution fin adjacent to the second end of the at least one folded perforated sheet, One end rod is adjacent to the first distribution fin, and the second end rod is adjacent to the second distribution fin to form a preliminary plate fin passage; and the preparatory plate fin passage of step (c) is placed on the first separation piece and the second separation The sheet fin passage is formed between the sheets; the plate fin passage of the step (d) is combined with the other fin fin passage to form the fin heat exchanger; and the plate fin heat exchanger is brazed.

One embodiment of the present invention is directed to a plate fin exchanger that includes perforated fins in at least a portion of the plate fin passages, and an assembly method for such plate fin exchangers. The perforated fins are assembled using flat perforated sheets. The fins formed have a special relationship to the perforation pattern on the flat sheet. While some finned channels have the aforementioned fins, other finned channels may have different types of fins, including flat, perforated, stripe offset, and wavy, for example. Plate fin heat exchangers containing such perforated fins have particular utility in cryogenic procedures such as air separation, but they can also be used in other heat transfer procedures.

Referring to Figure 1, the plate fin heat exchanger of the present invention comprises a plurality of plate fin passages, some of which are arranged by placing at least one fin 10 on the divider or plate 30, 40, side bars 50, 60, distribution Fins (not shown but generally known in the art) and end bars (not shown but generally known in the art) are made. These finned channels include special style perforations 20 in at least a portion of the finned channels.

Prior to being formed into fins 10 of FIG. 1, the fins 10 are flat sheets of metal such as aluminum, copper, another alloy, or any other thermally conductive material known in the art for making fins. The flat fins 10, as exemplified in FIG. 2, include the perforations 20. The flat sheet has a special perforation pattern comprising a plurality of parallel rows of perforations 100, 200, 300, and each parallel row 100, 200, 300 comprises perforations 1A, 1B, 1C; 2A, 2B, 2C; and 3A, 3B, 3C. In a specific embodiment, when the flat sheet is folded to form the fin 10 as described in FIG. 1, the perforated rows 1A, 1B, 1C; 2A, 2B, 2C; and 3A, 3B, 3C will be aligned with The fins are oriented in a direction parallel to the expected direction. When the fins are in the form of a simple fin, the flow reference line will be parallel to the perforation direction illustrated in Figure 2.

The perforations as illustrated in Figure 2 have a diameter (D). The spacing between the parallel rows of perforations 100, 200, 300 is designated S1, and the spacing between successive perforations in the direction of flow of the stream (i.e., between the perforations 2A and 2B) is designated S2. The offset between adjacent parallel rows of perforations 100, 200, 300 (i.e., between 2A and 3A) is designated S3.

In one embodiment, the Applicant has found unexpected results when the following parameters are maintained within the following ranges: (1) the diameter D of the perforations is in the range of 1 mm to 4 mm; and (2) the opening area is between 5% and 25%. Range; (3) S3/S2 ratio in the range of 0.25 to 0.75; and (4) S1/D ratio in the range of 0.75 to 2.0, with an optimum range of 0.75 to 1.0, such plate fin heat exchangers and A properly designed conventional heat exchanger exhibits higher efficiency and improved performance.

In an optimal configuration/embodiment, the fluid flow direction is parallel to the parallel rows of perforations 100, 200, 300, but in a preferred configuration/embodiment the fluid flow direction is 5 degrees in the direction of the parallel rows of perforations 100, 200, 300. (5%) or less. This means that when the fins are formed, the fins 10 should be folded such that the angle between the fin folds and the parallel rows of perforations 100, 200, 300 is less than or equal to 5 degrees, and the optimum configuration is for this angle It is 0 degrees (0°).

The fins 10 can include a plurality of perforations 20, which are illustrated as circular in FIGS. 1 and 2, however, those skilled in the art will appreciate that non-circular perforations can also be used including, but not limited to, elliptical, Perforations of rectangles, parallelograms, and shapes of such shapes.

In yet another embodiment, the arrangement of the offset rows of perforations can be repeated every two rows as illustrated in Figure 2 (i.e., row 100 will be offset similar to rows 300, 500 (not shown) ), 700 (not shown), etc.). Moreover, when the flat perforated sheets are folded into fins during the finning operation, the perforated formations produced on the finished fins 10 tend to be complex due to the mechanical details of how the material flows in the finned molds. relationship. In one embodiment, the flat sheet is folded such that the perforation pattern on the finished fin 10 is at least fifty percent (50%) of the heat exchanger finned passage containing the perforated fins, more preferably At least 80% (80%) of the finned channels, and preferably at least once every 10 fin wavelengths in 100% (100%) of the finned channels and preferably Repeat at least once every 5 fin wavelengths.

In another embodiment, the surface texture can be applied to the perforated sheet before the material is folded into a fin, such as U.S. Patent No. 6,834,515 B2, entitled "Plate Fin Exchangers with Textured Surfaces," granted to Sunder et al. The teachings are hereby incorporated by reference in their entirety. The surface texture can also be established in the process of creating fins from the flat perforated sheets.

The specific embodiments described herein are applicable to plate fin heat exchangers wherein at least a portion of the fins have a height in the range of 0.25 吋 to 1 吋 (.635 cm to 2.54 cm), more preferably 0.4 吋 to The range of 0.75 吋 (1.016 cm to 1.905 cm), and optimally ranges from 0.5 吋 to 0.6 吋 (1.27 cm to 1.524 cm). Such embodiments will be advantageously employed when the fluid flow conditions in such plate fin passages are in a transitional state between laminar and disturbing dynamics or in disturbing dynamics. This can be expressed as a Reynolds number range of 800 to 100,000 and more preferably in the range of 1,000 to 10,000. The Reynolds number is calculated according to the following formula:

Re=ρVD/μ, where

among them,

Re=Reynolds number;

ρ = fluid density;

V = fluid velocity;

μ = fluid viscosity;

D=4A/P;

A = fluid flow cross-sectional area; and

P = fluid flow parameters

With regard to the plate fin passage, the hydraulic diameter D is often calculated on the basis of individual fin passages and the current calculation is based on the use of the tantalum sheet without adjusting the perforations for A (fluid flow cross-sectional area) and P (fluid flow). The contribution of the parameter).

Particular embodiments of the present invention are of great value because plate fin heat exchangers are manufactured more closely than conventional plate fin exchangers, thus saving the combined investment and operating costs of equipment, such as air separation plants.

Example 1

To better understand the effects of perforations within the fin geometry, several sample problems were solved using computational fluid dynamics (CFD). In the use of this technique, the calculation results are often limited to some repetitive configurations in order to limit the computational reality of the problem. However, when one attempts to quantify the effect of the perforation pattern, the overall geometry of the heat exchanger is very complex, even when one limits the problem to a single sub-channel within the plate fin channel. Different types of approximations are used for this reason.

In most plate fin exchangers, the secondary surface area tends to be a major part of the total area. As previously mentioned, this is the area represented by the fins of the separator sheets or sheets 30, 40 that represent the major surface area. To understand the effects of such perforation alignments, a model of a representative periodic region of two infinite parallel plates is created to quantify the heat transfer and pressure loss that occurs as air flows therethrough. The general structure of the perforations on the flat sheet is illustrated in FIG.

Embodiment 1 relates to a simple fin for heat transfer and/or distribution purposes, wherein, as previously described, the flow direction is substantially parallel to the fin direction indicated in FIG.

Many of the demonstration cases are solved using CFD, where the different spacings (S1, S2, and S3) are varied with the diameter (D) of the perforations and the overall aperture area remaining the same. Specifically, the intervals S1 and S2 are simultaneously changed, and the offset S3 is set to be equal to half of the interval S2. In these exemplary cases, there is only one independent parameter and is listed in Table 1 and illustrated in Figure 3.

The exemplary calculation results show the relative values of the pressure donation and heat transfer rate obtained only by changing the pattern of perforations. The exemplary data is traced after scaling with respect to the value produced when the ratio of the spacing to the size of the aperture is about 3. When this ratio is reduced to about 2, heat transfer is significantly improved. As mentioned in Table 1, the increase in heat transfer is higher than the increment of the corresponding pressure loss. Therefore, the heat exchanger designed at a ratio of 2 can be shortened by about 1.2 times compared with the heat exchanger designed at a ratio of 3, and the overall pressure loss is also low. This is a significant reduction in length and volume. If the ratio falls below 2, the improvement is continued and a particularly good value is obtained between the ratios between 0.75 and 1. The heat transfer is improved by about 1.25 times in this ratio range. The required length or volume is the derivative of this ratio, in other words 0.80 or 80% (80%). This means that the physical size is reduced by 20% (20%), and the pressure loss is also reduced by 1.18/1.25, which is equivalent to 0.94 or 94% (94%). Therefore, the length or volume can be reduced by 20% (20%) and the pressure loss is also reduced by 6% (6%).

These are significant improvements that can be obtained by configuring the perforation locations as disclosed herein, which are not previously known or disclosed. In fact, some of the previous disclosures do not teach such configurations by arbitrarily expressing statements, associations or illustrations. As exemplified in Fig. 3, a range of ratios from 0.75 to 2.0 is preferred, with a range of from 0.75 to 1.0 being particularly preferred.

Example 2

Example 2 illustrates an exemplary improvement obtained using the teachings contained herein. As previously mentioned, the teachings of conventional perforated fins in plate fin heat exchangers do not discuss preferred geometries or perforation patterns as outlined herein. However, the previously cited CFD paper by Zhu et al. does not investigate the effect of specifying perforated fins compared to other types of fins such as flat, serrated, and wavy fins. This embodiment was produced in the same manner as described in Example 1 by applying the perforation pattern used in the CFD paper by Zhu et al.

The parameters of the perforation pattern on the flat layers before being folded into fins are as follows: perforation diameter (D) = 0.8 mm; opening area = 20%; S1 = 1.81 mm; S2 = 1.39 mm; and S3 = 0. The relative performance of the heat exchanger calculated using these prior art fins is shown in Table 2.

As exemplified in Table 2, since the relative heat transfer coefficient and relative pressure gradient of the disclosed exemplary embodiment are 26% higher than the heat exchanger of the CFD paper, constructing according to the disclosed exemplary embodiment The heat exchanger can have a shorter relative length (short 21%) and a smaller relative volume (21% smaller) than the heat exchanger constructed according to the CFD paper. Two of the heat exchangers have equal or matched heat transfer rates and pressure drops. This is a substantial benefit of using the fins made in accordance with the teachings of the disclosed exemplary embodiments to go beyond the teachings of the CFD paper.

Although the aspects of the invention have been described in connection with the preferred embodiments of the various embodiments, it is understood that other specific embodiments may be employed or modified or supplemented. The same functions of the present invention are made without departing from the invention. For example, the following aspects should also be understood as part of this disclosure:

Aspect 1. A plate fin heat exchanger comprising: a folded fin comprising a fin having a height, a width and a length, the folded fin being disposed on the first separator and the second separator And a first side bar and a second side bar, wherein the first side bar is disposed between the first partitioning piece and the second dividing piece and adjacent to the first side of the folded fin, and Wherein the second side bar is disposed between the first partitioning piece and the second dividing piece and adjacent to the second side of the folded fin, thereby forming at least a portion of the plate fin passage; wherein the fin comprises a plurality of perforations, When the fins are in a deployed shape, the plurality of perforations are arranged in a plurality of parallel rows on the fins, and the parallel rows of perforations on the fins include a first spacing (S1) between the parallel rows of perforations, a second spacing (S2) between successive perforations in the parallel row of perforations, a third spacing (or offset) between the perforations in adjacent parallel rows of perforations (S3), and a perforation diameter (D) ) wherein the ratio of the first spacing between the parallel rows of perforations to the diameter of the perforations (S1/D) is in the range of 0.75 to 2.0, and the angle between the fins and the parallel rows of perforations is less than or equal to 5 degrees (= 5°).

Aspect 2. The finned heat exchanger of Aspect 1, wherein the angle between the fins and the parallel rows of perforations is 0 degrees (0°).

Aspect 3. The plate fin heat exchanger of Aspect 1 or Aspect 2, wherein the ratio of the first spacing between the parallel rows of perforations to the diameter of the perforations (S1/D) is between 0.75 and 1.0 The scope.

A plate fin heat exchanger according to any one of Aspect 1 to 3, wherein a third pitch (or offset) between the perforations in adjacent parallel rows of perforations (S3) The ratio of the second spacing (S2) between the continuous perforations in the parallel row of perforations is in the range of 0.25 to 0.75.

The sheet fin heat exchanger of any one of aspect 1 to 4, wherein the perforations occupy 5% to 25% of the area of the folded fins in a developed shape.

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

A plate fin heat exchanger according to any one of Aspects 1 to 6, wherein the perforations are circular.

The plate fin heat exchanger according to any one of Aspects 1 to 6, wherein the perforations are in the shape of an ellipse, a rectangle or a parallelogram.

The plate fin heat exchanger of any one of aspect 1 to 8, wherein the adjacent parallel rows of perforations are offset in a staggered manner such that the positions of the parallel rows of perforations are every other row The perforation is repeated.

A plate fin heat exchanger according to any one of the aspects 1 to 8, wherein at least 50% of the heat exchanger fin passages of the perforated fins are more preferably Of at least 80% of the finned channels, and optimally within 100% of the finned channels, the adjacent parallel rows of perforations are offset such that the fins of the folded fin are parallel The perforation position is repeated exactly at least once every 10 fin wavelengths and more preferably at least once every 5 fin wavelengths.

The sheet fin heat exchanger of any one of aspect 1 to 10, wherein the folded fin comprises a surface texture.

The plate fin heat exchanger according to any one of the aspects 1 to 11, wherein the fin height is in the range of 0.25 吋 to 1 ,, more preferably in the range of 0.4 吋 to 0.75 ,, And optimally in the range of 0.5 吋 to 0.6 。.

A plate fin heat exchanger according to any one of the aspects 1 to 12, wherein the folded fin is a simple heat transfer fin or a distribution fin.

A plate fin heat exchanger according to any one of aspects 1 to 13, wherein the finned passage is adapted to receive a fluid flow, and wherein the fluid flows in the fin passage length Heat transfer is carried out at least 80%, more preferably within at least 90%, and optimally within 100% without phase change.

Aspect 15. A method of performing heat exchange between at least two streams in a plate fin heat exchanger constructed according to any of the aspect 1 to aspect 13, wherein at least one stream Performing heat transfer at least 80% of the length of the finned passages without phase change, and wherein the Reynolds number of the at least one stream is in the range of 800 to 100,000 and more preferably in the range of 1,000 to 10,000 in.

A method of separating nitrogen, oxygen, and/or argon from air by cryogenic distillation, which utilizes the fin-fin heat exchanger of any one of Aspects 1 to 13, wherein at least one of the streams is Within at least 80% of the length of the finned passage, more preferably within at least 90% of the length of the finned passages, and preferably within 100% of the length of the finned passages without heat transfer A phase change occurs.

Aspect 17. A method of manufacturing a plate fin heat exchanger comprising the steps of:

(a) providing at least one perforated sheet, the at least one perforated sheet comprising a plurality of perforations arranged in a plurality of parallel rows, wherein the parallel rows of perforations on the perforated sheet comprise a first spacing between the parallel rows of perforations (S1 a second spacing (S2) between successive perforations in the parallel row of perforations, a third spacing (or offset) between the perforations in adjacent parallel rows of perforations (S3), and a perforation diameter (D), wherein a ratio (S1/D) of the first spacing between the parallel rows of perforations to the diameter of the perforations is in the range of 0.75 to 2.0;

(b) folding the at least one perforated sheet into fins to form a folded perforated sheet such that an angle between the fins and the parallel rows of perforations is less than or equal to 5 degrees (= 5°);

(c) placing a first side bar adjacent the first side of the at least one folded perforated sheet, the second side rod abutting the second side of the at least one folded perforated sheet, the first dispensing fin being adjacent to the at least one folded perforated sheet a first end, the second distribution fin is adjacent to the second end of the at least one folded perforated sheet, the first end rod is adjacent to the first distribution fin, and the second end rod is adjacent to the second distribution fin to form a preparatory fin passage ;

(d) placing the preparatory plate fin passage of step (c) between the first separator sheet and the second separator sheet to form a plate fin passage therebetween;

(e) combining the plate fin channel of step (d) with other plate fin channels to form the plate fin heat exchanger;

(f) Brazing the plate fin heat exchanger.

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

Therefore, the invention as claimed should not be limited to any single embodiment or form, but should be determined in the broad sense and in the scope of the appended claims.

1A. . . perforation

1B. . . perforation

1C. . . perforation

2A. . . perforation

2B. . . perforation

2C. . . perforation

3A. . . perforation

3B. . . perforation

3C. . . perforation

D. . . diameter

S1. . . Spacing between parallel rows of perforations

S2. . . Spacing between successive perforations

S3. . . Offset between adjacent parallel rows of perforations

10. . . Fin

20. . . perforation

30. . . Partition plate

40. . . Partition plate

50. . . Side bar

60. . . Side bar

100. . . Parallel perforation

200. . . Parallel perforation

300. . . Parallel perforation

The foregoing description, as well as the detailed description of the exemplary embodiments, Exemplary embodiments are shown in the drawings for purposes of illustrating specific embodiments; however, the invention is not limited to the disclosed methods and tools. In these figures:

1 is an exploded perspective view of a basic or sub-assembly of a finned plate fin heat exchanger having perforated patterns and geometries in accordance with an embodiment of the present invention;

2 is a schematic view illustrating a specific embodiment of a perforation pattern on a flat plate before a flat plate is formed into a fin according to the present invention; and

Figure 3 is a graph illustrating the relative heat transfer rate and pressure loss performance of a perforated fin as a function of S1/D and indicating a preferred range.

10. . . Fin

20. . . perforation

30. . . Partition plate

40. . . Partition plate

50. . . Side bar

60. . . Side bar

Claims (30)

A plate fin heat exchanger comprising: a folded fin comprising a fin having a height, a width and a length, the folded fin being disposed between the first separator and the second separator; a first side bar and a second side bar, wherein the first side bar is disposed between the first dividing piece and the second dividing piece and adjacent to the first side of the folded fin, and the second side thereof a side bar is disposed between the first separator and the second separator and adjacent to the second side of the folded fin, thereby forming at least a portion of the plate fin passage; wherein the fin includes a plurality of perforations, when the fin The plurality of perforations are arranged in a plurality of parallel rows on the fins, and the parallel rows of perforations on the fins comprise a first spacing (S1) between the parallel rows of perforations, between the parallels a second spacing (S2) between successive perforations in the row of perforations, a third spacing (or offset) between the perforations in adjacent perforations of perforations (S3), and a perforation diameter (D) The ratio of the first spacing between the parallel rows of perforations to the diameter of the perforations (S1/D) Range of 0.75 to 2.0, and wherein the angle between these lines and the fin parallel rows of such perforations is less than or equal to 5 degrees ( 5°). The plate fin heat exchanger of claim 1, wherein the angle between the fins and the parallel rows of perforations is 0 degrees (0°). Such as the plate fin heat exchanger of claim 1 of the patent scope, wherein the The ratio of the first spacing between the parallel rows of perforations to the diameter of the perforations (S1/D) is in the range of 0.75 to 1.0. The plate fin heat exchanger of claim 1, wherein a third spacing (or offset) between the perforations in adjacent parallel rows of perforations (S3) and a perforation between the parallel rows of perforations The ratio of the second spacing (S2) between successive perforations is in the range of 0.25 to 0.75. A plate fin heat exchanger according to claim 1, wherein the perforations occupy 5% to 25% of the expanded fin area. A plate fin heat exchanger according to claim 1, wherein the perforation diameter (D) is in the range of 1 mm to 4 mm. A plate fin heat exchanger according to claim 1, wherein the perforations are circular. A plate fin heat exchanger according to claim 1, wherein the perforations are in the shape of an ellipse, a rectangle or a parallelogram. A plate fin heat exchanger according to claim 1, wherein the adjacent parallel rows of perforations are offset in a staggered manner such that the positions of the parallel rows of perforations are repeated every other row of perforations. The plate fin heat exchanger of claim 1, wherein at least 50% of the heat exchanger fin passages of the perforated fins are offset such that the adjacent parallel rows of perforations are offset The parallel row of perforation locations on the fins of the folded fins are repeated exactly at least once every 10 fin wavelengths. The plate fin heat exchanger of claim 1, wherein at least 80% of the heat exchanger fin passages of the perforated fins are offset such that the adjacent parallel rows of perforations are offset The parallel row of perforation locations on the fins of the folded fins are repeated exactly at least once every 10 fin wavelengths. The plate fin heat exchanger of claim 1, wherein in the 100% of the heat exchanger plate fin passages of the perforated fins, the adjacent parallel row perforations are offset so that The parallel row of perforation locations on the fins of the folded fins are repeated exactly at least once every 10 fin wavelengths. The plate fin heat exchanger of claim 1, wherein at least 50% of the heat exchanger fin passages of the perforated fins are offset such that the adjacent parallel rows of perforations are offset The parallel rows of perforations on the fins of the folded fins are repeated exactly at least once every 5 fin wavelengths. The plate fin heat exchanger of claim 1, wherein at least 80% of the heat exchanger fin passages of the perforated fins are offset such that the adjacent parallel rows of perforations are offset The parallel rows of perforations on the fins of the folded fins are repeated exactly at least once every 5 fin wavelengths. The plate fin heat exchanger of claim 1, wherein in the 100% of the heat exchanger plate fin passages of the perforated fins, the adjacent parallel row perforations are offset so that The parallel row of perforation locations on the fins of the folded fins are repeated exactly at least once every 5 fin wavelengths. A plate fin heat exchanger according to claim 1, wherein the folded fin comprises a surface texture. A plate fin heat exchanger according to claim 1, wherein the fin height is in the range of 0.25 吋 to 1 。. The plate fin heat exchanger of claim 1, wherein the fin height is in the range of 0.4 吋 to 0.75 。. The plate fin heat exchanger of claim 1, wherein the fin height is in the range of 0.5 吋 to 0.6 。. A plate fin heat exchanger according to claim 1, wherein the folded fin is a simple heat transfer fin or a distribution fin. The plate fin heat exchanger of claim 1, wherein the finned passages are adapted to receive a fluid flow, and wherein the fluid flows through at least 80% of the length of the finned passages for heat transfer No phase change Chemical. The plate fin heat exchanger of claim 1, wherein the finned passages are adapted to receive a fluid flow, and wherein the fluid flows through at least 90% of the length of the finned passages for heat transfer No phase change will occur. The plate fin heat exchanger of claim 1, wherein the finned passages are adapted to receive a fluid flow, and wherein the fluid flows within 100% of the length of the finned passages for heat transfer without A phase change will occur. A method for performing heat exchange between at least two streams in a plate fin heat exchanger according to claim 1, wherein at least one stream is heat transferred within at least 80% of the length of the finned passages The phase change does not occur, and the Reynolds Number of the at least one stream is in the range of 800 to 100,000. The method of claim 24, wherein the Reynolds Number of the at least one stream is in the range of 1,000 to 10,000. A method for separating nitrogen, oxygen and/or argon from air by cryogenic distillation, which utilizes a plate fin heat exchanger according to claim 1, wherein at least one of the lengths of the finned passages is at least 80 Heat transfer is performed within % without phase change. The method of claim 26, wherein the at least one stream is heat transferred within at least 90% of the length of the finned channels without phase change. The method of claim 26, wherein the at least one stream is heat transferred within 100% of the length of the finned channels without phase change. A method for manufacturing a plate fin heat exchanger, comprising the steps of: (a) providing at least one perforated sheet, the at least one perforated sheet comprising a plurality of perforations arranged in a plurality of parallel rows, wherein the parallel perforations on the perforated sheet A first spacing (S1) between the parallel rows of perforations, a second spacing (S2) between successive perforations in the parallel rows of perforations, and a perforation between adjacent parallel rows of perforations a third spacing (or offset) (S3) and a perforation diameter (D), wherein the ratio of the first spacing between the parallel rows of perforations to the diameter of the perforations (S1/D) is between 0.75 and 2.0 (b) folding the at least one perforated sheet into fins to form a folded perforated sheet such that the angle between the fins and the parallel rows of perforations is less than or equal to 5 degrees ( 5°); (c) placing the first side bar adjacent to the first side of the at least one folded perforated sheet, the second side rod adjacent to the second side of the at least one folded perforated sheet, the first dispensing fin being adjacent to the at least one Folding the first end of the perforated sheet, the second distribution fin is adjacent to the second end of the at least one folded perforated sheet, the first end rod is adjacent to the first distribution fin, and the second end rod is adjacent to the second distribution fin to form a preparation a finned passage; (d) placing the preparatory fin passage of step (c) between the first separator and the second separator to form a plate fin passage therebetween; (e) combining the step (d) a finned channel and other plate fin passages to form the plate fin heat exchanger; and (f) brazing the plate fin heat exchanger. The method for manufacturing a plate fin heat exchanger according to claim 29, further comprising applying a surface texture to the at least one perforated sheet before folding the at least one perforated sheet in the step (b).