A shell-and-tube heat exchanger and control method that eliminates leakage and bypass flow

Abstract

The application relates to a shell-and-tube heat exchanger and a control method for eliminating leakage flow and bypass flow, which comprises a shell side shell, a flow separation baffle, a tube box, a tube plate, a support plate, a pull rod, a connecting pipe, a support, a baffle and a heat exchange tube, a plurality of baffle tube holes are arranged on the baffle, a multilayer baffle is arranged on the baffle, or a tube hole gap sealing ring is arranged on the baffle; a composite outer edge is arranged at the edge position of the baffle, an outer contour cage of the heat exchange tube is arranged in the shell side shell, and a gradually changing transition configuration heat exchange tube group is arranged in the tube plate area; the application has the advantages that the leakage flow of A flow path and E flow path fluids and the bypass flow of C flow path and F flow path fluids of the shell-and-tube heat exchanger are directly eliminated, the total flow of the shell side of the heat exchanger is reduced, the resistance drop of the heat exchanger is reduced, the operation energy consumption is reduced, the heat exchange tube vibration is reduced, and the heat exchange efficiency of the heat exchanger is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of heat exchanger technology, and more particularly to a shell-and-tube heat exchanger and control method for eliminating leakage and bypass flow. Background Technology

[0002] Heat exchangers, also known as heat transfer devices, are energy-saving devices that facilitate heat transfer between materials. They are widely used in various industrial and agricultural sectors and are ubiquitous in daily life, especially in the petroleum, chemical, petrochemical, metallurgical, power, light industry, and food industries, where they are an indispensable process equipment. In oil refining and chemical plants, heat exchangers account for approximately 40% of the total equipment and 30%-45% of the total investment. In recent years, with the development of energy-saving technologies, their application areas have continued to expand, and the use of heat exchangers for high-temperature and low-temperature heat recovery has brought significant economic benefits. Classified by heat transfer principle, there are direct contact heat exchangers, energy storage heat exchangers, and plate / tube heat exchangers. Plate / tube heat exchangers are the most widely used, accounting for over 99% of the total. Their principle is that a hot medium transfers heat to a cold medium through a metal or non-metal interface. These heat exchangers are commonly referred to as shell-and-tube, plate, plate-fin, or plate-shell heat exchangers. Currently, shell-and-tube heat exchangers are the most widely used type of heat exchange equipment.

[0003] Shell-and-tube heat exchangers connect heat exchange tubes to a tube sheet, which is then fixed in place by a shell. They are broadly classified into fixed tube sheet type (e.g.,...) Figure 29 ), floating head type (such as Figure 30 ), U-shaped tube type (such as Figure 31 ), double-shell heat exchangers (such as Figure 32 ), external stuffing box type (such as Figure 33 Types of shell-and-tube heat exchangers include stuffing box and sliding tube sheet types. The design and manufacture of various shell-and-tube heat exchangers are based on factors such as the type, pressure, temperature, fouling, and other conditions of the medium, the connection method between the tube sheet and the shell, the form and heat transfer conditions of the heat exchange tubes, cost, ease of maintenance and inspection, and the characteristics of various structural forms.

[0004] The shell side of a shell-and-tube heat exchanger mainly consists of components such as baffles, support plates, partitions, bypass baffles, anti-impact plates, tie rods, spacers, guide tubes, slide plates, and heat exchange tubes. Due to the different process performance and applications of various types of heat exchangers, the arrangement of these components within the shell side also varies to meet various design requirements. These components, arranged within the shell side, can be divided into two categories according to their different functions. One category consists of various baffles, such as baffles, longitudinal baffles, bypass baffles, partitions, dummy tubes, and guide tubes, installed to maximize the flow of the shell-side medium to the heat exchange tubes and improve heat exchange efficiency. The other category consists of components for the installation of the tube bundle and the protection of the heat exchange tubes, such as support plates, guide rails, and anti-impact plates.

[0005] There are gaps between the baffles and the inner wall of the shell in shell-and-tube heat exchangers, as well as between the baffle tube holes and the tubes, which can cause leakage. This is a result that cannot be avoided by existing manufacturing and assembly technologies.

[0006] Since Tinker introduced the concept of flow path, flow path analysis has been widely considered the most ideal method for analyzing problems based on the actual distribution of the fluid. Flow path analysis is based on Tinker's physical model, dividing the shell-side fluid into five streams (A, B, C, E, and F) for study. Figure 34 In the picture:

[0007] A-flow path – the leakage flow path in the radial gap between the baffle plate orifice and the outer diameter of the tube;

[0008] B-flow path – the cross-flow path (effective cross-flow path) that passes through the heat exchange tubes, which is the main fluid that undergoes heat exchange;

[0009] C-flow path – the bypass flow path between the outer periphery of the tube bundle and the inner wall of the shell;

[0010] E-flow path – the leakage flow path between the outer circle of the baffle and the inner wall of the shell;

[0011] F-flow path – the intermediate through-flow path within the partitioned area of ​​a multi-pass heat exchanger or the wide channel between U-shaped tube passes (single-pass heat exchangers do not have this flow path), is a bypass flow path.

[0012] According to the aforementioned shell-side fluid flow model, the flow rates of the five fluid streams each account for a certain proportion of the total fluid. From a heat transfer perspective, designers should maximize the flow rate of fluid stream B and suppress the flow rates of the other four fluid streams. This is because, at the same flow rate, the heat transfer of fluids A, C, E, and F is much weaker than that of fluid stream B. When the mass fraction of fluid stream B reaches 80%, the shell-side fluid is in an ideal state, but this is difficult to achieve in actual operating conditions. Palen et al. obtained the mass fraction of each fluid stream under normal conditions through experiments.

[0013] The main objective of shell-side structural design is to increase the mass fraction of fluid B and reduce the mass fraction of bypass fluids C and F and leakage fluids A and E, thereby improving shell-side heat transfer efficiency.

[0014] The existing technology controls the fluid in each flow path as follows:

[0015] Control of fluid flow in the A-channel:

[0016] The flow rate of the fluid in the A-channel flow path is related to the radial clearance between the heat exchange tubes and the baffle tube orifices. This radial clearance is related to the tube assembly process during manufacturing. During design, the clearance should be minimized while ensuring manufacturing requirements are met, in order to reduce the mass fraction of the A-channel fluid and decrease the possibility of fluid-induced tube bundle vibration. Standards including TEMA "Shell and Tube Heat Exchangers" and GB / T 151 "Heat Exchangers" have specified corresponding regulations on the diameter and permissible deviations of the baffle tube orifices to control the radial clearance between the heat exchange tubes and the baffle tube orifices.

[0017] TEMA standard gap value:

[0018] TEMA standards stipulate that all heat exchanger tubes must be high-precision, and the clearance between the baffle tube holes and the heat exchanger tubes depends only on the length and diameter of the heat exchanger tubes. TEMA RCB-4.2 specifies:

[0019] ① The maximum unsupported length of the pipe is 914.4 mm (36″) or the outer diameter of the pipe is greater than 31.8 mm (1 1 / 4″), and the baffle tube orifice value is 0.80 mm (1 / 32″) larger than the outer diameter of the pipe.

[0020] ② For unsupported tubes with a maximum length exceeding 914.4 mm (36″) and an outer diameter of 31.8 mm (1 1 / 4″) or smaller, the standard baffle orifice is 0.40 mm (1 / 64″) larger than the outer diameter of the tube.

[0021] Control of E-strand fluid:

[0022] The E-flow can be controlled by adjusting the gap between the inner diameter of the shell and the outer diameter of the baffle. However, a smaller gap is not always better. Heat transfer requires a small gap, while manufacturing or maintenance may require a larger gap. Standards such as TEMA "Shell and Tube Heat Exchangers" and GB / T 151 "Heat Exchangers" specify the outer diameter of the baffle and its permissible deviation to control the gap between the inner diameter of the shell and the outer diameter of the baffle.

[0023] Control of C-flow fluid:

[0024] The flow rate of the C-flow fluid is closely related to the pipe arrangement and the number of pipes. Fewer pipes result in a larger gap between the outer edge of the tube bundle and the inner diameter of the shell cylinder. To reduce pressure drop at the shell-side inlet and outlet, a non-pipe zone must be reserved within the shell-side pipe arrangement based on the size of the shell-side nozzles. This can increase the C-flow fluid discharge channel. Currently, the following measures are generally taken to control the C-flow fluid:

[0025] 1) Increase the number of tubes, especially in non-inlet / outlet areas. Near the edge of the baffle, tie rods, spacers, or sealing strips can be used to supplement or seal the tubes. 2) Install an external guide tube so that the heat exchange tubes can fill the entire shell-side space. This method can both increase the number of heat exchange tubes to enhance heat transfer and minimize the pressure drop at the inlet and outlet.

[0026] Control of F-flow:

[0027] For multi-pass heat exchangers and U-tube heat exchangers, according to the existing technology, the shell-side region behind the partition plate and the minimum bend radius region of the U-tube are empty. There are no heat exchange tubes in this region and it is impossible to arrange them. Therefore, the fluid flow resistance in this region is less than that in the tube-arranged region. The shell-side fluid flows through this region at a faster flow rate than in the tube-arranged region without exchanging heat with the tube-side fluid in the heat exchange tubes. It is equivalent to taking a bypass. The path of the shell-side fluid flowing through this region is the F-flow path.

[0028] F-flow only occurs in U-tube heat exchangers and multi-pass heat exchangers, and only when the partition plate groove and the baffle plate notch are perpendicular. For U-tube heat exchangers, due to the minimum bend radius limitation of the U-tube heat exchanger tubes, the leakage path for F-flow is larger than in other heat exchangers, so baffles are added to the back of the partition plate groove. U-tube heat exchangers require intermediate baffles or a 45° rotation of the innermost U-tube arrangement to reduce spacing; the positions of the baffles and baffles are specified in GB / T 151 "Heat Exchangers". Under current technology, due to the minimum bend radius limitation of the U-tubes, the central part of the heat exchanger, where there is no tube bundle, has low flow resistance, meaning more F-flow flows through; while in the tube bundle area, flow resistance is high, the fluid flow rate is low, and the heat exchange is small. While current technology uses baffles or baffles to improve this somewhat, the effect is limited.

[0029] Of the five fluid streams (A, B, C, E, and F), only stream B—the cross-flow stream passing through the heat exchange tubes—is the main fluid for heat exchange and has the best heat transfer effect. The proportion of stream B should be maximized. The remaining four streams (A, C, E, and F) have very poor heat transfer effects and their proportions should be minimized or eliminated. Stream A has a gap between the baffle tube orifice and the outer diameter of the heat exchange tube, and stream E has a gap between the baffle and the inner wall of the shell. These two streams are due to fluid leakage issues caused by existing manufacturing and assembly techniques. Additionally, stream C is the bypass stream between the outer perimeter of the tube bundle and the inner wall of the shell, and stream F is the intermediate through-flow stream within the wide channel between U-shaped tube passes due to the limitation of the minimum bend radius of the multi-pass partition area or U-shaped tubes. These two streams are due to fluid bypass issues caused by structural reasons. Existing technologies have not fundamentally solved the problems of leakage and bypass of fluids in the A, C, E, and F flow paths. This greatly reduces the heat exchange efficiency of the heat exchanger, increases the resistance drop of the heat exchanger, increases the heat exchange area in the design of the heat exchanger, and leads to higher investment costs and increased operating energy consumption. Summary of the Invention

[0030] In view of the above problems, the purpose of this invention is to provide a shell-and-tube heat exchanger and control method for eliminating leakage and bypass flow, so as to fundamentally and directly eliminate the leakage and bypass problems of fluid in the flow path, thereby overcoming the shortcomings of the prior art.

[0031] This invention provides a shell-and-tube heat exchanger that eliminates leakage and bypass flow, comprising: a shell-side shell, a partition plate, a tube box, a tube sheet, a support plate, a tie rod, a connecting pipe, a support, a baffle plate, and heat exchange tubes. The baffle plate has multiple baffle plate holes for the tube bundle to pass through. The improvement is that the baffle plate is provided with a multi-layer baffle plate or a tube hole gap sealing ring is provided on the baffle plate.

[0032] The multilayer baffle plate has a multilayer tube hole that is concentric with the baffle tube hole and has a diameter smaller than the outer diameter of the heat exchange tube at the baffle tube hole in the corresponding baffle plate for passing through the heat exchange tube. The multilayer tube hole is fitted on the heat exchange tube. The diameter of the multilayer tube hole is smaller than the diameter of the heat exchange tube. The edge of the multilayer tube hole has a notch.

[0033] The tube hole gap sealing ring is fixed to the side wall of the baffle plate and located on the upstream side of the fluid inside the shell side. The tube hole gap sealing ring is located in the gap between the tube hole of the baffle plate through which the heat exchange tube passes and the outer diameter of the heat exchange tube. The inner diameter of the tube hole gap sealing ring is smaller than the diameter of the heat exchange tube.

[0034] As a preferred embodiment of the present invention, the multilayer baffle or the multilayer tube hole position of the multilayer baffle and the tube hole gap sealing ring are made of elastic or flexible material or deformable metal sheet material.

[0035] As a preferred embodiment of the present invention, the multilayer baffle, whose overall shape corresponds to that of the baffle plate, is fixedly connected to the baffle plate, or multiple split multilayer baffles are distributed at the baffle plate tube holes for passing through the heat exchange tubes, and the multilayer baffle is located on the upstream side of the fluid inside the shell. When the heat exchange tube passes through the tube hole of the base baffle plate and then through the multilayer tube hole, the multilayer tube hole undergoes bending deformation and fits tightly against the outer wall of the heat exchange tube, thereby eliminating the gap between the heat exchange tube and the baffle plate tube hole, blocking the leakage flow path here, and eliminating the A-channel flow path.

[0036] As a preferred embodiment of the present invention, the diameter of the multilayer baffle is larger than the inner diameter of the shell, and the outer edge of the multilayer baffle is located between the inner wall of the shell side and the edge of the baffle. When the baffle penetrates the shell side, it causes the outer edge of the multilayer baffle to bend and deform and stick tightly to the inner wall of the shell, blocking the leakage flow path at this point, that is, eliminating the E-flow path.

[0037] As a preferred embodiment of the present invention, a heat exchange tube outline cage is provided inside the shell side. The heat exchange tubes in the heat exchange tube outline cage are finned heat exchange tubes, that is, all heat exchange tubes located on the entire outer perimeter of the tube bundle are finned heat exchange tubes. The outer edges of the fins of all finned heat exchange tubes form a finned baffle cage. A gap is left between the fins of two adjacent finned heat exchange tubes, and the gap serves as a balancing hole. Alternatively, the heat exchange tube outline cage is a baffle cage formed by multiple thin plates that completely surround a set of heat exchange tubes along the outer perimeter of the set of heat exchange tubes. The thin plates are fixed to the heat exchange tubes or tie rods located at the edge of the tube bundle. A balancing hole is opened on the thin plates. Alternatively, the heat exchange tube outline cage is a thin plate wound cage formed by wrapping a set of heat exchange tubes along the outer perimeter of the set of heat exchange tubes with thin plate cage strips. A gap is left between adjacent thin plate cage strips, and the gap serves as a balancing hole, eliminating the C-flow path and simultaneously eliminating the E-flow path.

[0038] As a preferred embodiment of the present invention, a heat exchange tube outline-shaped bypass baffle is provided inside the shell side. The heat exchange tube outline-shaped bypass baffle is disposed in the annular space between a set of heat exchange tube outlines and the inner wall of the shell. The heat exchange tube outline-shaped bypass baffle is not pressure-bearing and only occupies the space through which C-flow path passes. The heat exchange tube outline-shaped bypass baffle is made of a flexible, elastic or porous material to eliminate the C-flow path.

[0039] Preferably, the tube sheet region is provided with a gradually transitioning heat exchange tube assembly, which covers the F-flow path region. The gradually transitioning heat exchange tube assembly comprises multiple gradually transitioning heat exchange tubes, each including a short straight tube section, a bend, and a long straight tube section. The short straight tube section transitions to the long straight tube section via a gradually transitioning bend. Each section of the gradually transitioning heat exchange tube lies within a single plane. The plane is perpendicular to the plane of the partition plate, the short straight pipe section is parallel to the long straight pipe section, and the bent pipe sections on both sides of the partition plate are mirror symmetrical. The distance between the short straight pipe section and the long straight pipe section of the gradually transition configuration heat exchange tube is the largest in the row of gradually transition configuration heat exchange tubes closest to the partition plate, and decreases row by row as the tube row moves away from the partition plate. The distance between the short straight pipe section and the long straight pipe section is the smallest in the row of gradually transition configuration heat exchange tubes farthest from the partition plate, thus eliminating the F flow path.

[0040] As a preferred embodiment of the present invention, the shell-side casing of the U-tube heat exchanger is provided with a gradually transitioning U-shaped heat exchange tube. The gradually transitioning U-shaped heat exchange tube comprises: two end straight tube sections, two short straight tube sections connected to the U-shaped tube sections, four gradually transitioning bends, two intermediate straight tube sections, and one U-shaped tube section. The end straight tube sections are used for insertion into the tube sheet, transition through the gradually transitioning bends to the intermediate straight tube sections used for heat exchange, then through the gradually transitioning bends to the short straight tube sections connected to the U-shaped tube sections, and finally to the U-shaped tube section. All tube sections of the gradually transitioning heat exchange tube lie in a single plane, which is the same as the plane containing the partition plate. The tubes are perpendicular to each other. The short straight tubes connecting the end straight tubes and the U-shaped tubes on each side are in a straight line. The middle straight tubes are parallel to the two end straight tubes. The gradually changing configuration bends on both sides connected to the U-shaped tubes are mirror symmetrical. The gradually changing configuration U-shaped heat exchange tubes in the same row are the same. The spacing between the middle straight tubes of adjacent rows of gradually changing configuration U-shaped heat exchange tubes is equal. The spacing between the two end straight tubes and the middle straight tubes of the gradually changing configuration U-shaped heat exchange tubes is the largest in the row of gradually changing configuration U-shaped heat exchange tubes closest to the partition plate, and decreases row by row as the tubes move away from the partition plate, so as to minimize the spacing between the two end straight tubes and the middle straight tubes, thus eliminating the F flow path.

[0041] As a preferred embodiment of the present invention, the F-flow path region (tube sheet region) of the U-tube heat exchanger is provided with a heat exchange tube filling type heat exchange tube bundle. The heat exchange tube filling type heat exchange tube bundle comprises: at least one manifold and two rows of heat exchange tube bundles. In the two rows of heat exchange tube bundles, one end of the first row of tubes is connected to the manifold, and the other end passes through the tube sheet and is connected to the inlet chamber of the tube box; one end of the second row of tubes is connected to the manifold, and the other end passes through the tube sheet and is connected to the outlet chamber of the tube box. This eliminates the F-flow path and increases the heat exchange area of ​​the heat exchange tube filling type heat exchange tube bundle.

[0042] Another object of the present invention is to provide a design method for a shell-and-tube heat exchanger that eliminates leakage and bypass flow, comprising the following steps:

[0043] Step A: Set up a multi-layer baffle on the base baffle to form a composite baffle, or set a pipe hole gap sealing ring on the base baffle to eliminate flow path A;

[0044] Step A1: The function of the stratified baffle is to seal the gap between the baffle tube hole of the base baffle and the outer wall of the heat exchange tube, thereby eliminating the A-channel flow path. The stratified baffle is located on the upstream side of the fluid in the shell side. When the heat exchange tube passes through the composite baffle, it first passes through the base baffle and then through the stratified baffle. Since the stratified baffle has concentric baffle tube holes smaller than the outer diameter of the heat exchange tube, and small notches are provided on the stratified baffle tube holes, the stratified tube holes are elastic and / or flexible. After the heat exchange tube passes through the tube hole of the base baffle and then through the stratified tube hole, the stratified tube hole bends and deforms and fits tightly against the outer wall of the heat exchange tube, thereby eliminating the gap between the heat exchange tube and the baffle tube hole, blocking the leakage flow path at this point, and eliminating the A-channel flow path.

[0045] Step A2: Fix the tube hole gap sealing ring to the side wall of each base baffle plate and position it on the upstream side of the fluid inside the shell. The tube hole gap sealing ring is located at the gap between the baffle plate tube hole and the outer diameter of the heat exchange tube in the base baffle plate, and the diameter of the tube hole gap sealing ring is smaller than the diameter of the heat exchange tube. The tube hole gap sealing ring installed at the gap between the baffle plate tube hole and the outer diameter of the heat exchange tube in the base baffle plate blocks the leakage flow path at this point, thereby eliminating the A-channel flow path.

[0046] Step B: Increase the diameter of the multi-layered baffle or set a composite outer edge on the outer edge of the base layer baffle to eliminate the E-flow path;

[0047] Step B1: By setting the diameter of the stratified baffle to be larger than the inner diameter of the shell, the outer edge of the stratified baffle is located between the inner wall of the shell side and the edge of the base baffle. When the base baffle penetrates the shell side, it causes the outer edge of the stratified baffle to bend and deform and stick tightly to the inner wall of the shell, blocking the leakage flow path at this point and eliminating the E-flow path.

[0048] Step B2: Fix the outer edge of the composite type to the outer circumference of the base baffle. Since the outer edge of the composite type is made of elastic or flexible material, and the outer edge of the composite type is located between the inner wall of the shell and the edge of the base baffle, when the baffle penetrates the shell, it causes the outer edge of the composite type to bend and deform and stick tightly to the inner wall of the shell, blocking the leakage flow path here, that is, eliminating the E-flow path.

[0049] Step C: The heat exchanger tube outer profile cage is used as the quasi-boundary of the shell-side fluid. The main function of the shell-side shell is to bear pressure. The heat exchanger tube outer profile cage divides the fluid inside the shell-side shell into two parts. Since the heat exchanger tube outer profile cage is the inner and outer boundary of the fluid, one part of the fluid is outside the heat exchanger tube outer profile cage, blocking the fluid in the C-flow path within the annular gap between the inner wall of the shell-side shell and the outer side of the heat exchanger tube outer profile cage, keeping it in a quasi-static state. The other part of the fluid is inside the heat exchanger tube outer profile cage normally. The fluid flows normally with the heat exchange tubes; or a bypass baffle of the outer profile of the heat exchange tubes is used as the quasi-boundary of the shell-side fluid. Since the bypass baffle of the outer profile of the heat exchange tubes is set in the annular space between the outer profile of a set of heat exchange tubes and the inner wall of the shell, the bypass baffle of the outer profile of the heat exchange tubes is not pressurized and only occupies the space through which the C-flow passes. The material of the bypass baffle of the outer profile of the heat exchange tubes is a flexible, elastic or porous material. Since the E-flow path is included in the range of the C-flow path area, the E-flow path is naturally eliminated when the C-flow path is eliminated.

[0050] Step C1: The heat exchange tube outer contour cage adopts a fully enclosed form. The heat exchange tube outer contour cage is a baffle-type cage formed by multiple thin plates that completely surround a set of heat exchange tubes along the outer contour of the set of heat exchange tubes. The multiple thin plates are fixed to the tie rod or heat exchange tube located at the edge of the tube bundle and form an integral part with the set of heat exchange tubes. The thin plates are provided with balance holes. The thin plates block the C-flow path fluid in the annular gap between the inner wall of the shell side and the outer wall of the baffle-type cage, so that the C-flow path fluid is in a quasi-static region, thereby eliminating the C-flow path; or the heat exchange tube outer contour cage is a thin plate wound type cage formed by wrapping the set of heat exchange tubes along the outer contour of the set of heat exchange tubes with thin plate cage strips. There are gaps between adjacent thin plate cage strips. The gaps serve as balance holes. The thin plate wound type cage keeps the C-flow path fluid in a quasi-static region, thereby eliminating the C-flow path and naturally eliminating the E-flow path at the same time.

[0051] Step C2: The heat exchange tubes of the outer contour cage of the heat exchange tubes are finned heat exchange tubes, that is, all the heat exchange tubes located on the entire outer contour of the tube bundle are finned heat exchange tubes. The outer edges of the fins of all the finned heat exchange tubes form a finned baffle cage. A gap is left between the fins of two adjacent finned heat exchange tubes. This gap serves as a balancing hole. While eliminating the C flow path, the E flow path is naturally eliminated.

[0052] Step D: Eliminate F-flow paths by using heat exchanger tube bundles with gradually transitioned configurations or heat exchanger tube filler bundles;

[0053] Step D1: By arranging heat exchange tube bundles with a gradually transitional configuration in the tube sheet region, the straight tube sections of some heat exchange tubes in the tube arrangement area are relocated to the F-flow path region, so that the F-flow path region changes from a tubeless region with no heat exchange to a tube region with effective heat exchange, and the entire area inside the tube bundle outline becomes an effective heat exchange area, thereby eliminating the F-flow path.

[0054] Step D2: By arranging heat exchange tubes in a tube-filling configuration, the F-flow path region is transformed from a tubeless region with no heat exchange into a tube-containing region with effective heat exchange. The entire area within the outer contour of the tube bundle becomes an effective heat exchange zone, and the heat exchange area of ​​the tube-filling configuration is increased. The tube-filling configuration consists of at least one manifold and two rows of heat exchange tube bundles, thereby eliminating the F-flow path.

[0055] The beneficial effects of this invention are as follows:

[0056] 1. This invention fundamentally and directly eliminates the leakage of fluid in the A and E flow paths and the bypass flow of fluid in the C and F flow paths of the shell-and-tube heat exchanger, thereby reducing the total flow rate of the heat exchanger shell side, reducing the resistance drop of the heat exchanger, reducing operating energy consumption, suppressing or reducing the vibration of the heat exchange tubes, and greatly improving the heat exchange efficiency of the heat exchanger.

[0057] 2. The shell-and-tube heat exchanger of this invention is closely aligned with the current standard GB / T 151 "Heat Exchangers". The specifications of the heat exchange tubes, the arrangement of the heat exchange tubes, and the tube spacing can all be kept consistent with the current standard. Whether applied to newly constructed heat exchangers or to upgrade existing heat exchangers, it is highly compliant and easy to promote and apply.

[0058] 3. In contrast to the indirect technical measures used in the prior art, such as controlling gaps and tolerances to reduce the size of flow paths A and E, and adding bypass baffles and baffles to "block" ineffective flow paths C and F, the present invention adopts a direct connection arrangement to eliminate flow paths A, E, and C; and arranges effective heat exchange surfaces in the space occupied by ineffective flow paths such as F, thus making effective use of the ineffective space.

[0059] 4. This invention is based on the flow path analysis method, proposed by American scientist Tinker in 1947 and widely considered the most ideal model for shell-side flow in shell-and-tube heat exchangers. It utilizes fundamental principles of fluid mechanics to achieve innovative results. By integrating the control of leakage in flow paths A and E, and the bypassing of flow paths C and F, into a single heat exchanger, the heat exchange efficiency is significantly improved when all flow paths A, E, C, and F are eliminated, resulting in substantial benefits. Depending on the specific heat exchanger's design parameters, fluid properties, and operating characteristics, one, several, or all of these technical solutions can be selected to achieve the corresponding improvement in heat exchange efficiency.

[0060] 5. This invention has a wide range of applications and huge market potential. Its innovative technologies can be applied to almost all shell-and-tube heat exchangers. It can be used for both new equipment and the retrofitting of existing equipment. The innovative technologies for high-efficiency shell-and-tube heat exchangers (including the elimination of A, C, E, and F flow paths) will undoubtedly usher in a new era of innovation in the traditional shell-and-tube heat exchanger industry.

[0061] 6. The technical method of eliminating flow paths A, E, C, and F of the present invention can be used simultaneously, or one or a combination thereof. Attached Figure Description

[0062] Figure 1 This is a schematic diagram of a U-tube heat exchanger with a gradual transition configuration that directly eliminates leakage and bypass flow according to the present invention.

[0063] Figure 2 This is a schematic diagram of the base layer of the composite baffle plate for eliminating the A-channel flow path in this invention;

[0064] Figure 3 This is a schematic diagram of the multilayer composite baffle plate for eliminating the A-channel flow path in this invention;

[0065] Figure 4 This is a schematic diagram of the composite baffle plate for eliminating the A-channel flow path in this invention;

[0066] Figure 5 This is a schematic diagram of the installation of the composite baffle plate that eliminates the A-channel flow path in this invention;

[0067] Figure 6 This is a schematic diagram of the outer edge composite baffle plate for eliminating A+E flow paths in this invention;

[0068] Figure 7 This is a schematic diagram of the installation of the composite baffle plate at the outer edge of the A+E flow path in this invention;

[0069] Figure 8 This is a front view of the heat exchange tube outer profile cage that eliminates the C+E flow path in this invention;

[0070] Figure 9 This is a side view of the outer profile cage of the heat exchange tube in this invention, which eliminates the C+E flow path.

[0071] Figure 10 This is a front view of the heat exchange tube outline bypass baffle that eliminates the C+E flow path in this invention;

[0072] Figure 11 This is a side view of the bypass baffle body of the heat exchange tube that eliminates the C+E flow path in this invention.

[0073] Figure 12 This is a schematic diagram of the U-shaped heat exchange tube (U-tube heat exchanger) with a gradually transitioned configuration that eliminates the F-flow path in this invention;

[0074] Figure 13 This is a schematic diagram of the heat exchanger tube with a gradual transition configuration in the double tube sheet and multi-pass heat exchanger that eliminates the F-flow path in this invention.

[0075] Figure 14This is a schematic diagram of the U-shaped heat exchange tube bundle (U-shaped tube heat exchanger) with a gradual transition configuration that eliminates the F-flow path in this invention;

[0076] Figure 15 for Figure 14 Schematic diagram of AA section;

[0077] Figure 16 for Figure 14 Schematic diagram of the BB cross section;

[0078] Figure 17 This is a schematic diagram of the heat exchange tube bundle (double tube sheet heat exchanger) with a gradually transition configuration that eliminates the F-flow path in this invention.

[0079] Figure 18 for Figure 17 Schematic diagram of AA section;

[0080] Figure 19 for Figure 17 Schematic diagram of the BB cross section;

[0081] Figure 20 This is a schematic diagram of a heat exchange tube bundle (U-tube heat exchanger) that eliminates the F-flow path in the present invention.

[0082] Figure 21 This is a top view of the heat exchange tube bundle (U-tube heat exchanger) with empty space in the heat exchange tubes that eliminates the F-flow path in this invention.

[0083] Figure 22 This is an installation diagram of the heat exchange tube bundle (U-tube heat exchanger) with empty space in the heat exchange tubes that eliminates the F-flow path in this invention;

[0084] Figure 23 This is a side view of the heat exchange tube bundle (U-tube heat exchanger) with the F-flow path eliminated in this invention.

[0085] Figure 24 This is a schematic diagram illustrating an example of a tool for a heat exchanger tube with a gradually changing configuration in this invention.

[0086] Figure 25 This is a schematic diagram of a shell-and-tube heat exchanger with a filler tube bundle that directly eliminates leakage and bypass flow, according to the present invention.

[0087] Figure 26 The tube bundle outline for eliminating C+E flow paths in this invention adopts a finned heat exchange tube bundle main view;

[0088] Figure 27 The side view of the finned heat exchange tube bundle is used to eliminate the C+E flow path in this invention.

[0089] Figure 28The tube bundle outline for eliminating C+E flow paths in this invention adopts a finned heat exchange tube bundle C-node diagram;

[0090] Figure 29 This refers to the existing BEM vertical fixed tube sheet heat exchanger.

[0091] Figure 30 This refers to existing AES and BES floating head heat exchangers;

[0092] Figure 31 This refers to the existing BEU U-tube heat exchanger.

[0093] Figure 32 This refers to the existing AFP double-shell stuffed heat exchanger.

[0094] Figure 33 This refers to the existing AJW split-flow shell stuffing heat exchanger;

[0095] Figure 34 This is a schematic diagram of the flow path in the existing flow path analysis method.

[0096] Figure reference numerals: 1. Baffle plate; 2. Tube box; 3. Tube sheet; 4. Gasket; 5. Anti-impact plate; 6. Heat exchange tube outer profile cage; 7. Composite baffle; 7. Base layer baffle; 7-1. Multi-layer baffle; 7-2. Small notch; 7-2-1. Composite support plate; 8. Tie rod; 9. Shell side shell; 10. Nozzle; 11. Support; 12. Heat exchange tube; 13. Short straight tube section; 13-1. Bend section; 13-2. Long straight tube section; 13-3. Composite baffle with outer edge; 14. Base layer; 14-1. Multi-layer baffle; 14-2. Heat exchanger tube bundle 15, heat exchanger tube filling type heat exchanger tube bundle 16, manifold 16-1, heat exchanger tube bundle 16-2, gradually transitioning U-shaped heat exchanger tube 17, end straight tube section 17-1, gradually transitioning bend tube section 17-2, 17-4, intermediate straight tube section 17-3, short straight tube section 17-5, U-shaped tube section 17-6, finned heat exchanger tube 18, fin 18-1, base tube 18-2, heat exchanger tube outer contour type bypass baffle 19, baffle fastener 19-1, bypass baffle 19-2. Detailed Implementation

[0097] Example 1

[0098] A shell-and-tube heat exchanger that eliminates leakage and bypass flow, such as Figure 1 (U-tube heat exchanger with gradual transition configuration) and Figure 25(U-shaped tube heat exchanger with heat exchange tube filling type heat exchange tube bundle) is a structural assembly diagram of the present invention, including: partition plate 1, tube box 2, tube sheet 3, gasket 4, anti-impact plate 5, heat exchange tube outer contour cage 6, composite baffle 7, composite support plate 8, tie rod 9, shell side shell 10, pipe 11, support 12, heat exchange tube bundle with gradual transition configuration 13, composite baffle with outer edge (eliminating A+E flow path) 14, heat exchange tube bundle 15, heat exchange tube filling type heat exchange tube bundle 16, U-shaped heat exchange tube with gradual transition configuration 17, finned heat exchange tube 18, fin 18-1, base tube 18-2. The composite support plate 8 is also a composite support plate with the same structure as the composite baffle. The structure, material, and function of the support plate cladding are the same as those of the baffle cladding.

[0099] The technical solution for eliminating the A-share flow path in this embodiment is as follows:

[0100] The first option, see [link / reference] Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 The A-channel flow path is eliminated by the composite baffle 7, which includes a base baffle 7-1, a multi-layer baffle 7-2, and fasteners 7-3. The base baffle 7-1 of the composite baffle 7, such as... Figure 2 Existing baffles can be used as the base baffle 7-1. The form, notch, outer diameter and permissible deviation, minimum thickness, pipe hole center distance, pipe hole diameter and permissible deviation, baffle spacing, etc., of the base baffle 7-1 can be based on existing baffles. The cascade baffle 7-2, such as... Figure 3 The cascade baffle 7-2 has cascade tube holes concentric with the base baffle 7-1 and appropriately smaller than the outer diameter of the heat exchange tubes at all the tube holes corresponding to the base baffle 7-1. To facilitate tube installation, the cascade tube holes of the cascade baffle 7-2 can have small notches 7-2-1, or they can be omitted. The number, form, and size of the small notches are not limited and can be determined according to the cascade material. It is suitable for the cascade baffle 7-2 to fit against the outer wall of the heat exchange tube after the heat exchange tube 13 in the gradually transitioning configuration heat exchange tube group is installed. A schematic diagram of the composite baffle 7 is shown below. Figure 4The cascaded baffle 7-2 is fixed or solidified onto the base baffle 7-1, or the base baffle 7-1 and the cascaded baffle 7-2 can be made into a single composite material. The base baffle 7-1 is rigid, while the cascaded baffle 7-2 is elastic or flexible. This combination of rigidity and flexibility ensures that the gap between the tube holes of the composite baffle 7 and the outer wall of the heat exchange tube is close to "0," allowing the leakage A flow in the existing technology to revert to B flow, participating in efficient heat exchange and improving heat exchange efficiency. When the outer diameter of the cascaded baffle 7-2 is smaller than the inner diameter of the shell-side shell 10: the A flow path is eliminated; when the outer diameter of the cascaded baffle 7-2 is appropriately larger than the inner diameter of the shell-side shell 10: the A flow path + E flow path is eliminated. In this case, the composite baffle 7 is a composite baffle 14 with an outer edge that eliminates the A+E flow path. The composite baffle 7 eliminates flow path A. After the heat exchanger tubes are inserted and the shell-side casing 10 is installed, its side view is as follows: Figure 5 The function of the base layer baffle 7-1 is the same as that of the baffles in the prior art. The diameter of the cladding layer 14-2 of the composite baffle 14 with an outer edge is appropriately larger than the inner diameter of the shell 10. The function of the cladding layer 14-2 is to seal the gap between the tube hole of the base layer 14-1 of the composite baffle 14 with an outer edge and the outer wall of the heat exchange tube 13, as well as the gap between the base layer 14-1 of the composite baffle 14 with an outer edge and the inner wall of the shell 10. The base layer 14-1 and the cladding layer 14-2 of the composite baffle 14 are fixedly connected by connecting fasteners 14-3.

[0101] like Figure 6 , Figure 7 When the heat exchange tube 13 passes through the composite baffle 7 or the composite baffle 14 with an outer edge, the tube holes of the composite baffle 7-2 or the composite baffle 14 with an outer edge open and fit tightly against the outer wall of the heat exchange tube 13. Since the tube holes of the composite baffle 7-2 are concentric with the base baffle 7-1 and are appropriately smaller than the outer diameter of the heat exchange tube 13, and the tube holes of the composite baffle 7-2 are elastic or flexible, after the heat exchange tube 13 passes through the tube hole of the base baffle 7-1 and then through the tube hole of the composite baffle 7-2, the tube holes of the composite baffle 7-2 deform and fit tightly against the outer wall of the heat exchange tube 13, eliminating the gap between the outer diameter of the heat exchange tube 13 and the tube hole of the baffle 7, blocking the leakage flow path at this point, that is, eliminating the A flow path.

[0102] In this embodiment, the composite baffle 14 with an outer edge eliminates the A+E flow path. Since the outer edge diameter of the cladding layer 14-2 of the composite baffle 14 with an outer edge is larger than the inner diameter of the shell-side housing 10 and has elasticity or flexibility, when the composite baffle 14 with an outer edge or the tube bundle penetrates the shell-side housing 10, the outer edge of the cladding layer 14-2 of the composite baffle 14 with an outer edge bends and deforms and adheres tightly to the inner wall of the shell-side housing 10, blocking the leakage flow path at this point, thus eliminating the E flow path.

[0103] With the outer edge of the composite baffle 14's cladding layer 14-2 facing the upstream flow side of the fluid, according to fluid mechanics principles, the upstream pressure is greater than the downstream pressure. This pressure difference causes the tube holes of the cladding layer 14-2 to press tightly against the outer wall of each heat exchange tube in the heat exchange tube bundle 15. The cladding layer 14-2 of the composite baffle 14's cladding layer 14-2 also presses tightly against the mating surface of the base layer 14-1 of the composite baffle 14's cladding layer 14. The principle is the same when sealing the shell side of the shell 10. The composite baffle 14 with the outer edge eliminates the A+E flow path and also prevents or mitigates heat exchange tube vibration; the cladding layer 7 also possesses the above-mentioned effects. The materials of the cladding layer 7-2 and / or the cladding layer 14-2 of the composite baffle 14 with the outer edge can be metal, non-metal, or composite materials, and should be determined according to the heat exchanger parameters, fluid properties, etc.

[0104] In the second embodiment, a tube hole gap sealing ring is provided on the base layer baffle 7-1. The tube hole gap sealing ring is fixed to the side wall of the base layer baffle 7-1 and located on the upstream side of the fluid inside the shell 10. The tube hole gap sealing ring is located in the base layer baffle 7-1 at the gap between the baffle tube hole through which the heat exchange tube passes and the outer diameter of the heat exchange tube. The diameter of the tube hole gap sealing ring is smaller than the diameter of the heat exchange tube. The base layer baffle 7-1 and multiple tube hole gap sealing rings form a composite baffle 7 with the same function as the stratified baffle 7-2.

[0105] The elimination of the E-flow path in this embodiment includes the following two schemes:

[0106] The first option is a combination of eliminating the E-flow path and eliminating the A-flow path, such as... Figure 6 , Figure 7 The A+E flow path is eliminated by the composite baffle 14 with an outer edge. The composite baffle 14 with an outer edge eliminates the A+E flow path more effectively than the multi-layered baffle 7-2 (which eliminates the A flow path). This outer edge eliminates the E flow path. The multi-layered baffle 14-2 is larger than the inner diameter of the shell-side casing 10. The diameter of the multi-layered baffle 14-2 with the outer edge is larger than the inner diameter of the shell-side casing 10, thus eliminating both the A and E flow paths. See the explanation in the section on eliminating the A flow path for details.

[0107] The second option, namely the option to eliminate the E-flow separately: Eliminate the A+E flow path in the composite outer edge (eliminate the A+E flow path) 14, such as... Figure 6 , Figure 7 In the process, the multilayer baffle 7-2 that eliminates flow path A is removed, leaving only the outer edge of the multilayer 14-2 of the composite baffle 14 with an outer edge. Since the diameter of the outer edge of the multilayer 14-2 is larger than the inner diameter of the shell-side housing 10 and has elasticity or flexibility, when the composite baffle 14 with an outer edge penetrates the shell-side housing 10, the outer edge of the multilayer 14-2 bends and deforms and adheres tightly to the inner wall of the shell-side housing 10, blocking the leakage flow path at this point, thus eliminating flow path E.

[0108] Eliminating the C flow path in this embodiment includes two methods:

[0109] Option 1: Use a tubular outer-frame cage, also known as a fence or wall.

[0110] A bypass baffle cage (non-)fully enclosed for heat exchange tubes, serving as a fence around the outer contour of the tube bundle.

[0111] A heat exchange tube outer profile cage 6 is used to block and eliminate flow path C. For example... Figure 8 , Figure 9 .

[0112] The heat exchange tube outer contour cage 6 completely surrounds the heat exchange tube bundle 15 along its outer contour. Balance holes 6-3 are opened at appropriate intervals, ensuring that the heat exchange tube outer contour cage 6 is not pressurized and only blocks the flow of fluid in the C-flow path. This confines the C-flow fluid within the annular gap between the inner wall of the shell-side casing 10 and the outer wall of the heat exchange tube outer contour cage 6, creating a quasi-static region. Within this quasi-static region, the fluid is almost completely still, forming a self-sealing state. This prevents the C-flow, which does not participate in heat exchange and is essentially stagnant, from flowing, thus reducing the total flow rate of the fluid within the shell-side casing 10. This correspondingly reduces the pump load, saving energy and conserving flow by reducing the total circulation volume of the shell-side fluid. It's equivalent to slimming down the shell side. The primary function of the shell-side casing 10 is to bear pressure, and the heat exchange tube outer contour cage 6 serves as the quasi-boundary for the shell-side fluid.

[0113] The heat exchanger tube outer profile cage 6 is arranged in sections between multiple composite baffles 7. The heat exchanger tube outer profile cage 6 can be segmented for easy disassembly and replacement. The heat exchanger tube outer profile cage 6 can be fixed to the tie rod 9 or the heat exchanger tube bundle 15, serving as a component of the heat exchanger tube bundle 15. The heat exchanger tube outer profile cage 6 consists of detachable fasteners 6-1 and thin plates 6-2. The fasteners 6-1 fix the thin plates 6-2 to the tie rod 9 or the heat exchanger tube bundle 15. It is detachable and replaceable, such as… Figure 8 , Figure 9 Alternatively, the heat exchanger tube outer enclosure 6 may use finned heat exchanger tubes 18, which consist of fins 18-1 and base tubes 18-2. The finned heat exchanger tubes 18 are arranged on the outer contour of the heat exchanger tube bundle 15, serving as the outer enclosure of the tube bundle. For example... Figure 26 , 27 28.

[0114] A small gap is left between the fins 18-1 of two adjacent finned heat exchange tubes 18, which serves as a balancing hole. At the same time, the fins 18-1 also increase the effective heat exchange area, i.e., expand the tube surface. The fins 18-1 are welded or rolled onto the outer surface of the base tube 18-2.

[0115] Alternatively, thin plate cages can be wrapped around the outer contour of a set of heat exchange tube bundles 15, with gaps between adjacent thin plate cages to act as balancing holes. These cages are then fixed to the tie rods 9 of the tube bundle or the heat exchange tube bundle 15 by fasteners.

[0116] The second option: Use a fully enclosed bypass barrier or a non-fully enclosed bypass barrier. For example... Figure 10 , 11 A heat exchange tube outline-shaped bypass baffle 19 is provided inside the shell-side housing 10. The heat exchange tube outline-shaped bypass baffle 19 consists of a baffle fastener 19-1 and a bypass baffle 19-2. The baffle fastener 19-1 fixes the bypass baffle 19-2 to the tie rod 9 of the tube bundle or the heat exchange tube bundle 15. It is removable and replaceable. The heat exchange tube outline-shaped bypass baffle 19 is located in the annular space between the outer contour of a set of heat exchange tube bundles 15 and the inner wall of the shell-side housing 10. The heat exchange tube outline-shaped bypass baffle is not pressure-bearing and only occupies the space through which C streams of fluid pass. The heat exchange tube outline-shaped bypass baffle 19-2 is made of a flexible or elastic material. The material of the heat exchange tube outline-shaped bypass baffle 19-2 can be a sponge-like porous material.

[0117] The elimination of F-flow paths in this embodiment includes two technical solutions: the first solution is to adopt a heat exchanger tube group with a gradual transition configuration; the second solution is to use a heat exchanger tube bundle with a heat exchanger tube filling gap.

[0118] First option: Use the aforementioned gradually transitioning heat exchange tube 13. For example... Figure 12 , Figure 13 , Figure 14 , Figure 15 , Figure 16 , Figure 17 , Figure 18 , Figure 19 .

[0119] In this embodiment, a gradually transitioning heat exchange tube assembly is arranged in the F-flow path region where tubes cannot be laid in the prior art. The gradually transitioning heat exchange tube assembly arranged in the F-flow path region is achieved by relocating some of the straight tube sections of the heat exchange tube bundle 15 from the tube laying area to the F-flow path region through the bends 13-2 of multiple heat exchange tubes 13, thus transforming the F-flow path region from a tube-free region to a tube-containing region, and turning the entire area within the tube bundle outline into an effective heat exchange zone. In other words, all heat exchange tubes in the tube laying area are redistributed in a direction perpendicular to the partition plate 1. The redistributed heat exchange tubes 13 are as follows: the gradually transitioning heat exchange tubes in the same row are the same, the gradually transitioning heat exchange tubes in different rows are different, the long straight tube sections 13-3 of adjacent rows of gradually transitioning heat exchange tubes are evenly spaced, all sections of the gradually transitioning heat exchange tubes are in a plane, this plane is perpendicular to the plane of the partition plate 1, and all straight tube sections are parallel to the partition plate 1.

[0120] For multi-pass heat exchangers:

[0121] Each heat exchanger tube with a gradual transition configuration consists of a short straight tube section 13-1, a gradually transition bend section 13-2, and a long straight tube section 13-3. The short straight tube section 13-1 is used at the end of the partition plate, transitioning to the long straight tube section 13-3 via the gradually transition bend section 13-2. All tube sections of the gradually transition configuration heat exchanger tube lie in a single plane, perpendicular to the plane containing the partition plate 1. The short straight tube section 13-1 is parallel to the long straight tube section 13-3. The gradually transition configuration heat exchanger tube groups on both sides of the partition plate 1 are mirror-symmetrical. Within the same row of heat exchanger tubes 13, the gradually transition bend sections 13-2 are identical for each tube, and the entire heat exchanger tube 13 is also identical; however, the gradually transition bend sections 13-2 are not identical for different rows of heat exchanger tubes. The distance between the short straight tube section 13-1 and the long straight tube section 13-3 of the heat exchange tubes with the gradual transition configuration is the largest in the row of heat exchange tubes 13 closest to the partition plate 1, and decreases row by row as the tubes move further away from the partition plate 1. In the row of heat exchange tubes 13 farthest from the partition plate 1, the distance between the short straight tube section 13-1 and the long straight tube section 13-3 is equal to or close to zero.

[0122] For U-tube heat exchangers:

[0123] For a U-tube heat exchanger, a gradually transitioning U-shaped heat exchange tube 17 is installed in the shell 10 at the U-shaped tube section. The gradually transitioning U-shaped heat exchange tube 17 consists of two end straight tube sections 17-1, two short straight tube sections 17-5 connected to the U-shaped tube section, two sets of gradually transitioning bend sections 17-2 and 17-4, two intermediate straight tube sections 17-3, and one U-shaped tube section 17-6. The gradually transitioning heat exchange tubes on both sides connected to the U-shaped tube section 17-6 are mirror-symmetrical. Among them, the end straight tube section 17-1 is used to insert into the tube sheet 3, transitions through the gradually transitioning bend section 17-2 to the intermediate straight tube section 17-3 used for heat exchange, then transitions through the gradually transitioning bend section 17-4 to the short straight tube section 17-5 connected to the U-shaped tube section 17-6, and then connects to the U-shaped tube section 17-6. All sections of the U-shaped heat exchanger tube 17 with a gradual transition configuration lie in a single plane, which is perpendicular to the plane containing the partition plate 1. The short straight tube section 17-5 connecting the end straight tube section 17-1 and the U-shaped tube section 17-6 on each side is in a straight line, and the middle straight tube section 17-3 is parallel to the two end straight tube sections 17-1 and 17-5. The two sets of four gradually transitioning bend sections 17-2 and 17-4 are mirror-symmetrical. Within the same row of the U-shaped heat exchanger tubes with a gradual transition configuration, each gradually transitioning bend section 17-2 and 17-4 is identical, and the entire U-shaped heat exchanger tube 17 is also identical. However, within different rows of the U-shaped heat exchanger tubes with a gradual transition configuration, the gradually transitioning bend sections 17-2 and 17-4 are not identical, and the entire U-shaped heat exchanger tube 17 is also not identical. The distance between the two end straight pipe sections 17-1 and 17-5 and the middle straight pipe section 17-3 of the U-shaped heat exchange tube 17 with a gradual transition configuration is the largest in the row of U-shaped heat exchange tubes 17 closest to the partition plate 1, and decreases row by row as the tube row moves away from the partition plate 1. In the row of U-shaped heat exchange tubes 17 with a gradual transition configuration farthest from the partition plate 1, the distance between the two end straight pipe sections 17-1 and 17-5 and the middle straight pipe section 17-3 is equal to or close to zero.

[0124] The tube sheet 3 and its gradually transitioning U-shaped heat exchange tubes 17 may or may not follow the current standards in terms of tube hole arrangement.

[0125] The material of the U-shaped heat exchange tube 17 with the gradual transition configuration is the same as that of the existing technology.

[0126] Manufacturing, installation, and special tools for the gradient transition configuration U-shaped heat exchanger tube 17:

[0127] The manufacturing and processing of the U-shaped heat exchanger tube 17 with its gradual transition configuration is carried out concurrently with the installation of the heat exchanger tube bundle 15. The processing of the gradually bent tube sections 17-2 and 17-4 requires the use of tools. Examples of tools can be found in [link to example]. Figure 24 .

[0128] Recommended installation sequence for U-shaped heat exchanger tube 17 with gradual transition configuration:

[0129] 1. Tube sheet 3 and composite baffle 7 are manufactured.

[0130] 2. The U-shaped heat exchange tube 17 with gradual transition configuration first completes the processing of the following parts: U-shaped tube section 17-6, two short straight tube sections 17-5 connected to U-shaped tube section 17-6, two gradually bend tube sections 17-4, and two intermediate straight tube sections 17-3.

[0131] 3. Heat exchange tube 17 passes through composite baffle 7;

[0132] 4. Process and bend the two straight pipe sections 17-1 at both ends and the gradually bent pipe section 17-2 connected to them. At this time, since the pipe spacing is relatively small, the pipes can be bent in a certain bending sequence and using a pipe bending tool.

[0133] 5. The straight tube section 17-1 at the end of the heat exchange tube 17 is inserted into the tube sheet 3.

[0134] Second option: Heat exchanger tube bundle with void filling;

[0135] The structure of the heat exchange tube filling type heat exchange tube bundle 16 is such that the F-flow path region, where tubes cannot be laid under existing technology, is arranged with the heat exchange tube filling type heat exchange tube bundle, so that the F-flow path region is changed from a tubeless area to a tube-containing area, and the entire area inside the tube bundle outline becomes an effective heat exchange area. The heat exchange tube filling type heat exchange tube bundle consists of one or N manifolds 16-1 and two rows of heat exchange tube bundles 16-2. One end of the first row of heat exchange tube bundles is connected to the manifold, and the other end passes through the tube sheet and is connected to the inlet chamber of the tube box; one end of the second row of heat exchange tube bundles is connected to the manifold, and the other end passes through the tube sheet and is connected to the outlet chamber of the tube box.

[0136] Compared with existing technologies, the heat exchange tube bundle 16 with filled tubes increases the heat exchange area by two additional rows of tubes. The tube sheet 3 and its heat exchange tubes' perforations and arrangement can be adjusted according to current standards, with the addition of two rows of perforations for the heat exchange tube bundle with filled tubes, or not. It is advisable to appropriately thicken the support plate to bear the weight of the manifolds, etc.

[0137] Installation sequence: First, manufacture the manifold 16-1 and heat exchange tube bundle 16-2, and then weld the heat exchange tube filling type heat exchange tube bundle 16; then, the heat exchange tube filling type heat exchange tube bundle 16 passes through the composite baffle 7 and tube sheet 3; then, it passes through the U-shaped tube.

[0138] Example 2

[0139] This embodiment provides a design method for a shell-and-tube heat exchanger that eliminates leakage and bypass flow, including the following steps:

[0140] Step A: Use the existing baffle plate as the base baffle plate 7-1, and install a multi-layer baffle plate 7-2 on the base baffle plate 7-1, or install a pipe hole gap sealing ring on the base baffle plate 7-1 to eliminate flow path A;

[0141] Step A1: The function of the multi-layer baffle 7-2 is to seal the gap between the baffle tube holes of the base layer baffle 7-1 and the outer wall of each heat exchange tube in the heat exchange tube bundle 15, thereby eliminating the A-channel flow path. Specifically, when each heat exchange tube in the heat exchange tube bundle 15 passes through the composite baffle 7-2, it first passes through the base layer baffle 7-1, and then through the multi-layer baffle 7-2. This is because the multi-layer baffle 7-2 has concentric baffle tube holes smaller than the outer diameter of the heat exchange tubes, and the edges of the tube holes... The heat exchange tubes have two or more small openings to allow them to pass smoothly through the tube holes of the cladding baffle. The cladding tube holes are elastic and / or flexible. When each heat exchange tube in the heat exchange tube bundle 15 passes through the tube hole of the base baffle 7-1 and then through the cladding tube hole, the cladding tube hole bends and deforms and fits tightly against the outer wall of each heat exchange tube in the heat exchange tube bundle 15 to eliminate the gap between the heat exchange tube bundle 15 and the baffle tube hole, block the leakage flow path here, and eliminate the A-channel flow path.

[0142] Step A2: Fix the tube hole gap sealing ring to the side wall of each base layer baffle 7-1 and position it on the upstream side of the fluid inside the shell 10. The tube hole gap sealing ring is located at the gap between the baffle tube hole of the base layer baffle 7-1 and the outer diameter of the heat exchange tube bundle 15. The diameter of the tube hole gap sealing ring is smaller than the diameter of the heat exchange tube bundle 15. The tube hole gap sealing ring installed at the gap between the baffle tube hole of the base layer baffle 7-1 and the outer diameter of the heat exchange tube bundle 15 blocks the leakage flow path at this point, thereby eliminating the A-channel flow path.

[0143] Step B: Increase the diameter of the multi-layer baffle 7-2 or set a composite outer edge on the outer edge of the base layer baffle 7-1 to eliminate the E-flow path;

[0144] Step B1: By setting the diameter of the composite baffle 7-2 to be larger than that of the base baffle 7-1, i.e., baffle 14, the outer edge of the composite baffle 7-2 is located between the inner wall of the shell side housing 10 and the edge of the base baffle 7-1. When the composite baffle 14 penetrates the shell side housing 10, it causes the outer edge of the composite baffle 7-2 to bend and deform and stick tightly to the inner wall of the shell side housing 10, blocking the leakage flow path here and eliminating the E-channel flow path.

[0145] Step B2: The composite baffle 14 with an outer edge is fixed to the outer circumference of the base baffle 7-1. Since the composite baffle 14 with an outer edge is made of elastic or flexible material, and the composite baffle 14 with an outer edge is located between the inner wall of the shell-side shell 10 and the edge of the base baffle 7-1, when it is inserted into the shell-side shell 10, it causes the composite baffle 14 with an outer edge to bend and deform and stick tightly to the inner wall of the shell-side shell 10, blocking the leakage flow path here, that is, eliminating the E-channel flow path.

[0146] Step C: The heat exchange tube outer profile cage (or fence) 6 is used as the quasi-boundary of the heat exchange tubes. The main function of the shell-side shell 10 is to bear pressure. The heat exchange tube outer profile cage 6 divides the fluid inside the shell-side shell 10 into two parts. Since the heat exchange tube outer profile cage 6 is the inner and outer boundary of the fluid, one part of the fluid is outside the heat exchange tube outer profile cage 6, blocking (locking) the fluid of the C-flow path within the annular gap between the inner wall of the shell-side shell 10 and the outer side of the heat exchange tube outer profile cage 6, keeping it in a state of near-static equilibrium. The other part of the fluid is outside the heat exchange tube outer profile cage 6. The fluid flows normally within the enclosure 6 and exchanges heat normally with the heat exchange tube bundle 15. Alternatively, the heat exchange tube outer profile bypass baffle 6-1 can be used as the quasi-boundary of the heat exchange tubes. Since the heat exchange tube outer profile bypass baffle 6-1 is set in the annular space between the outer profile of a set of heat exchange tube bundles 15 and the inner wall of the shell side shell 10, the heat exchange tube outer profile bypass baffle 6-1 is not pressurized and only occupies the space through which C streams of fluid pass. The material of the heat exchange tube outer profile bypass baffle 6-1 is a flexible or elastic material, and the material of the heat exchange tube outer profile bypass baffle 6-1 is a sponge-like porous material.

[0147] Step C1: The heat exchange tube outer contour cage 6 adopts a fully enclosed form. The heat exchange tube outer contour cage 6 is a baffle-type cage formed by multiple thin plates that completely surround a set of heat exchange tube bundles 15 along the outer contour of a set of heat exchange tubes. The multiple thin plates are fixed to the heat exchange tube bundles 15 located at the edge and surround the set of heat exchange tube bundles 15 into one unit. The baffle-type cage is provided with balance holes. The baffle-type cage blocks the C-flow path fluid in the annular gap between the inner wall of the shell side shell 10 and the outer wall of the baffle-type cage, so that the C-flow path fluid is in the quasi-static region, thereby eliminating the C-flow path.

[0148] Step C2: The heat exchange tube outer contour cage 6 adopts a fully enclosed form. The heat exchange tubes at the heat exchange tube outer contour cage 6 are finned heat exchange tubes 18. The outer edges of the fins 18-1 of multiple finned heat exchange tubes 18 form a finned baffle cage. A gap is left between the fins 18-1 of two adjacent finned heat exchange tubes 18, and this gap serves as a balance hole; or the heat exchange tube outer contour cage 6 includes: thin plate cage strips wound on the heat exchange tubes. A gap is left between adjacent thin plate cage strips, and this gap serves as a balance hole, so that the C-flow path fluid is in a quasi-static region, thereby eliminating the C-flow path.

[0149] Step D: Use a heat exchanger tube bundle with a gradually transitioned configuration or a heat exchanger tube bundle with a gap-filling configuration 16 to eliminate the F-flow path;

[0150] Step D1: By arranging heat exchange tube bundles with a gradually transitional configuration in the tube sheet region, the straight tube sections of some heat exchange tubes in the tube arrangement area are relocated to the F-flow path region, so that the F-flow path region changes from a tubeless region to a tube-containing region, and the entire area inside the tube bundle outline becomes an effective heat exchange area, thereby eliminating the F-flow path.

[0151] Step D2: By arranging heat exchange tubes in the F-flow area of ​​the U-tube heat exchanger as a tube-filled heat exchange tube bundle 16, the F-flow area is transformed from a tubeless area to a tube-filled area, and the entire area within the outer contour of the tube bundle is transformed into an effective heat exchange area. The heat exchange tubes in the tube-filled heat exchange tube bundle 16 consists of at least one manifold 16-1 and two rows of heat exchange tube bundles. One end of the first row of tubes is connected to the manifold, and the other end passes through the tube sheet and is connected to the inlet chamber of the tube box. One end of the second row of tubes is connected to the manifold, and the other end passes through the tube sheet and is connected to the outlet chamber of the tube box.

[0152] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A shell and tube heat exchanger that eliminates leakage and bypass flow, comprising: The package includes a shell, a partition plate, a tube box, a tube sheet, a support plate, a tie rod, a connecting pipe, a support, a baffle plate, and heat exchange tubes. The baffle plate has multiple baffle plate holes for the tube bundle to pass through. The package is characterized by having a multi-layer baffle plate or a tube hole gap sealing ring on the baffle plate. The multilayer baffle plate has a multilayer tube hole that is concentric with the baffle tube hole and has a diameter smaller than the outer diameter of the heat exchange tube at the baffle tube hole in the corresponding baffle plate for passing through the heat exchange tube. The multilayer tube hole is fitted on the heat exchange tube. The diameter of the multilayer tube hole is smaller than the diameter of the heat exchange tube. The edge of the multilayer tube hole has a notch. The tube hole gap sealing ring is fixed to the side wall of the baffle plate and located on the upstream side of the fluid inside the shell side. The tube hole gap sealing ring is located in the gap between the tube hole of the baffle plate through which the heat exchange tube passes and the outer diameter of the heat exchange tube. The inner diameter of the tube hole gap sealing ring is smaller than the diameter of the heat exchange tube.

2. A shell and tube heat exchanger to eliminate leakage and bypass flow as claimed in claim 1 wherein, The multilayer baffle or the multilayer pipe hole position of the multilayer baffle, the pipe hole gap sealing ring is made of elastic or flexible material, or deformable metal sheet material.

3. A shell and tube heat exchanger to eliminate leakage and bypass flow as claimed in claim 1 wherein, The stratified baffle, whose overall shape corresponds to that of the baffle plate, is fixedly connected to the baffle plate. Alternatively, multiple separate stratified baffles are distributed at the baffle plate tube holes for passing through the heat exchange tubes. The stratified baffle is located on the upstream side of the fluid inside the shell. When the heat exchange tube passes through the tube hole of the base baffle plate and then through the stratified tube hole, the stratified tube hole undergoes bending deformation and fits tightly against the outer wall of the heat exchange tube to eliminate the gap between the heat exchange tube and the baffle plate tube hole, blocking the leakage flow path and eliminating the A-channel flow path.

4. A shell-and-tube heat exchanger for eliminating leakage and bypass flow according to claim 1, characterized in that, The diameter of the multilayer baffle is larger than the inner diameter of the shell. The outer edge of the multilayer baffle is located between the inner wall of the shell and the edge of the baffle. When the baffle penetrates the shell, it causes the outer edge of the multilayer baffle to bend and deform and stick tightly to the inner wall of the shell, blocking the leakage flow path at this point, that is, eliminating the E-flow path.

5. A shell and tube heat exchanger to eliminate leakage and bypass flow as claimed in claim 1 wherein, The shell-side casing is equipped with a heat exchange tube outline cage. The heat exchange tubes in the heat exchange tube outline cage are finned heat exchange tubes, that is, all heat exchange tubes located on the entire outer perimeter of the tube bundle are finned heat exchange tubes. The outer edges of the fins of all finned heat exchange tubes form a finned baffle-type cage. A gap is left between the fins of two adjacent finned heat exchange tubes, and the gap serves as a balancing hole. Alternatively, the heat exchange tube outline cage is a baffle-type cage formed by multiple thin plates that completely surround a set of heat exchange tubes along the outer perimeter of the set of heat exchange tubes. The thin plates are fixed to the heat exchange tubes or tie rods located at the edge of the tube bundle. A balancing hole is opened on the thin plates. Alternatively, the heat exchange tube outline cage is a thin plate wound type cage formed by wrapping a set of heat exchange tubes along the outer perimeter of the set of heat exchange tubes with thin plate cage strips. A gap is left between adjacent thin plate cage strips, and the gap serves as a balancing hole, eliminating the C-flow path and simultaneously eliminating the E-flow path.

6. A shell and tube heat exchanger to eliminate leakage and bypass flow as claimed in claim 1 wherein, The shell side is provided with a heat exchange tube outline-shaped bypass baffle. The heat exchange tube outline-shaped bypass baffle is located in the annular space between a set of heat exchange tube outlines and the inner wall of the shell. The heat exchange tube outline-shaped bypass baffle is not pressure-bearing and only occupies the space through which C-flow path passes. The heat exchange tube outline-shaped bypass baffle is made of flexible, elastic or porous material to eliminate the C-flow path.

7. A shell and tube heat exchanger to eliminate leakage and bypass flow as claimed in any one of claims 1 to 6 wherein, The tube sheet region is equipped with a gradually transitioning heat exchange tube assembly, which covers the F-flow path region. The gradually transitioning heat exchange tube assembly comprises multiple gradually transitioning heat exchange tubes, each including a short straight tube section, a bend section, and a long straight tube section. The short straight tube section transitions to the long straight tube section via a gradually transitioning bend section. Each section of the gradually transitioning heat exchange tube lies within a single plane, which is aligned with the distribution plane. The plane containing the partition plate is perpendicular, the short straight pipe section is parallel to the long straight pipe section, and the bent pipe sections on both sides of the partition plate are mirror symmetrical. The distance between the short and long straight pipe sections of the gradually transitioning heat exchange tubes is largest in the row of gradually transitioning heat exchange tubes closest to the partition plate, and decreases row by row as the tubes move away from the partition plate. The distance between the short and long straight pipe sections of the gradually transitioning heat exchange tubes furthest from the partition plate is smallest, thus eliminating the F-flow path.

8. A shell and tube heat exchanger to eliminate leakage and bypass flow as claimed in any one of claims 1 to 6 wherein, The shell-side casing of the U-tube heat exchanger is equipped with a gradually transitioning U-shaped heat exchange tube configuration. This configuration includes: two end straight tube sections, two short straight tube sections connected to the U-shaped tube sections, four gradually transitioning bends, two intermediate straight tube sections, and one U-shaped tube section. The end straight tube sections are used for insertion into the tube sheet. They transition through the gradually transitioning bends to the intermediate straight tube sections used for heat exchange, then through the gradually transitioning bends to the short straight tube sections connected to the U-shaped tube sections, and finally to the U-shaped tube section. All tube sections of the gradually transitioning heat exchange tube configuration lie in a single plane, perpendicular to the plane of the partition plate. The short straight pipe sections connecting the end straight pipe sections and the U-shaped pipe sections on each side are in a straight line. The middle straight pipe section is parallel to the two end straight pipe sections. The gradually changing configuration bends on both sides connected to the U-shaped pipe sections are mirror symmetrical. The gradually changing configuration U-shaped heat exchange tubes in the same row are identical. The spacing between the middle straight pipe sections of adjacent rows of gradually changing configuration U-shaped heat exchange tubes is equal. The spacing between the two end straight pipe sections and the middle straight pipe section of the gradually changing configuration U-shaped heat exchange tube is the largest in the row of gradually changing configuration U-shaped heat exchange tubes closest to the partition plate, and decreases row by row as the tube row moves away from the partition plate, so as to minimize the spacing between the two end straight pipe sections and the middle straight pipe section, thus eliminating the F flow path.

9. A shell and tube heat exchanger to eliminate leakage and bypass flow as claimed in any one of claims 1 to 6 wherein, The F-flow path region of the U-tube heat exchanger is equipped with a heat exchange tube filler type heat exchange tube bundle. The heat exchange tube filler type heat exchange tube bundle consists of at least one manifold and two rows of heat exchange tube bundles. In the two rows of heat exchange tube bundles, one end of the first row of tubes is connected to the manifold, and the other end passes through the tube sheet and is connected to the inlet chamber of the tube box. One end of the second row of tubes is connected to the manifold, and the other end passes through the tube sheet and is connected to the outlet chamber of the tube box. This eliminates the F-flow path and increases the heat exchange area of ​​the heat exchange tube filler type heat exchange tube bundle.

10. The design method of a shell-and-tube heat exchanger for eliminating leakage and bypass flow according to claim 1, characterized in that, Includes the following steps: Step A: Set up a multi-layer baffle on the base baffle to form a composite baffle, or set a pipe hole gap sealing ring on the base baffle to eliminate flow path A; Step A1: The function of the stratified baffle is to seal the gap between the baffle tube hole of the base baffle and the outer wall of the heat exchange tube, thereby eliminating the A-channel flow path. The stratified baffle is located on the upstream side of the fluid in the shell side. When the heat exchange tube passes through the composite baffle, it first passes through the base baffle and then through the stratified baffle. Since the stratified baffle has concentric baffle tube holes smaller than the outer diameter of the heat exchange tube, and small notches are provided on the stratified baffle tube holes, the stratified tube holes are elastic and / or flexible. After the heat exchange tube passes through the tube hole of the base baffle and then through the stratified tube hole, the stratified tube hole bends and deforms and fits tightly against the outer wall of the heat exchange tube, thereby eliminating the gap between the heat exchange tube and the baffle tube hole, blocking the leakage flow path at this point, and eliminating the A-channel flow path. Step A2: Fix the tube hole gap sealing ring to the side wall of each base baffle plate and position it on the upstream side of the fluid inside the shell. The tube hole gap sealing ring is located at the gap between the baffle plate tube hole and the outer diameter of the heat exchange tube in the base baffle plate, and the diameter of the tube hole gap sealing ring is smaller than the diameter of the heat exchange tube. The tube hole gap sealing ring installed at the gap between the baffle plate tube hole and the outer diameter of the heat exchange tube in the base baffle plate blocks the leakage flow path at this point, thereby eliminating the A-channel flow path. Step B: Increase the diameter of the multi-layered baffle or set a composite outer edge on the outer edge of the base layer baffle to eliminate the E-flow path; Step B1: By setting the diameter of the stratified baffle to be larger than the inner diameter of the shell, the outer edge of the stratified baffle is located between the inner wall of the shell side and the edge of the base baffle. When the base baffle penetrates the shell side, it causes the outer edge of the stratified baffle to bend and deform and stick tightly to the inner wall of the shell, blocking the leakage flow path at this point and eliminating the E-flow path. Step B2: Fix the outer edge of the composite type to the outer circumference of the base baffle. Since the outer edge of the composite type is made of elastic or flexible material, and the outer edge of the composite type is located between the inner wall of the shell and the edge of the base baffle, when the baffle penetrates the shell, it causes the outer edge of the composite type to bend and deform and stick tightly to the inner wall of the shell, blocking the leakage flow path here, that is, eliminating the E-flow path. Step C: The heat exchanger tube outer profile cage is used as the quasi-boundary of the shell-side fluid. The main function of the shell-side shell is to bear pressure. The heat exchanger tube outer profile cage divides the fluid inside the shell-side shell into two parts. Since the heat exchanger tube outer profile cage is the inner and outer boundary of the fluid, one part of the fluid is outside the heat exchanger tube outer profile cage, blocking the fluid in the C-flow path within the annular gap between the inner wall of the shell-side shell and the outer side of the heat exchanger tube outer profile cage, keeping it in a quasi-static state. The other part of the fluid is inside the heat exchanger tube outer profile cage normally. The fluid flows normally with the heat exchange tubes; or a bypass baffle of the outer profile of the heat exchange tubes is used as the quasi-boundary of the shell-side fluid. Since the bypass baffle of the outer profile of the heat exchange tubes is set in the annular space between the outer profile of a set of heat exchange tubes and the inner wall of the shell, the bypass baffle of the outer profile of the heat exchange tubes is not pressurized and only occupies the space through which the C-flow passes. The material of the bypass baffle of the outer profile of the heat exchange tubes is a flexible, elastic or porous material. Since the E-flow path is included in the range of the C-flow path area, the E-flow path is naturally eliminated when the C-flow path is eliminated. Step C1: The heat exchange tube outer contour cage adopts a fully enclosed form. The heat exchange tube outer contour cage is a baffle-type cage formed by multiple thin plates that completely surround a set of heat exchange tubes along the outer contour of the set of heat exchange tubes. The multiple thin plates are fixed to the tie rod or heat exchange tube located at the edge of the tube bundle and form an integral part with the set of heat exchange tubes. The thin plates are provided with balance holes. The thin plates block the C-flow path fluid in the annular gap between the inner wall of the shell side and the outer wall of the baffle-type cage, so that the C-flow path fluid is in a quasi-static region, thereby eliminating the C-flow path; or the heat exchange tube outer contour cage is a thin plate wound type cage formed by wrapping the set of heat exchange tubes along the outer contour of the set of heat exchange tubes with thin plate cage strips. There are gaps between adjacent thin plate cage strips. The gaps serve as balance holes. The thin plate wound type cage keeps the C-flow path fluid in a quasi-static region, thereby eliminating the C-flow path and naturally eliminating the E-flow path at the same time. Step C2: The heat exchange tubes of the outer contour cage of the heat exchange tubes are finned heat exchange tubes, that is, all the heat exchange tubes located on the entire outer contour of the tube bundle are finned heat exchange tubes. The outer edges of the fins of all the finned heat exchange tubes form a finned baffle cage. A gap is left between the fins of two adjacent finned heat exchange tubes. This gap serves as a balancing hole. While eliminating the C flow path, the E flow path is naturally eliminated. Step D: Eliminate F-flow paths by using heat exchanger tube bundles with gradually transitioned configurations or heat exchanger tube filler bundles; Step D1: By arranging heat exchange tube bundles with a gradually transitional configuration in the tube sheet region, the straight tube sections of some heat exchange tubes in the tube arrangement area are relocated to the F-flow path region, so that the F-flow path region changes from a tubeless region with no heat exchange to a tube region with effective heat exchange, and the entire area inside the tube bundle outline becomes an effective heat exchange area, thereby eliminating the F-flow path. Step D2: by arranging the heat exchange pipe bundle to fill the gap, the F stock flow path area changes from the no heat exchange no pipe area to the effective heat exchange pipe area, the whole area within the pipe bundle contour becomes an effective heat exchange area, and the heat exchange area of the heat exchange pipe bundle filling type is increased. The heat exchange pipe bundle filling type is composed of at least one header and two rows of heat exchange pipe bundle row pipe groups, which realizes the elimination of F stock flow path.

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