A shell-and-tube heat exchanger head and a shell-and-tube heat exchanger

Abstract

This invention proposes a shell-and-tube heat exchanger head and a shell-and-tube heat exchanger. The head includes a tube sheet, a cap, and a partition. The cap is a curved shell structure and is fixedly mounted on the tube sheet. The cap and tube sheet enclose a flow cavity. Three sets of mounting holes are spaced apart on the tube sheet, each set including multiple mounting holes. These mounting holes are used to fix the tube bundle inside the heat exchanger. The partition is inclined and positioned in the flow cavity. One end of the partition is fixedly connected to the inner wall of the cap, and the other end is fixedly connected to the tube sheet. The partition divides the flow cavity into a switching cavity and a single-pass cavity. The inclination direction of the partition faces two adjacent sets of mounting holes, and these two adjacent sets of mounting holes are located within the switching cavity. By inclining the partition, the fluid flow path in the switching cavity can be optimized, reducing local resistance loss and backflow, improving the uniformity of fluid distribution, and making the fluid flow more stable within the switching cavity, thereby improving the heat exchange efficiency and overall performance of the heat exchanger.

Description

TECHNICAL FIELD

[0001] The present application relates to heat exchanger technical field, especially to a tube and shell heat exchanger head and a tube and shell heat exchanger. BACKGROUND

[0002] The heat exchanger is the key heat exchange equipment of industrial thermal process, wherein the tube and shell heat exchanger is widely used in energy, petroleum, chemical industry, metallurgy and aerospace and other various industrial fields due to its mature technology, simple structure, low cost, wide flow cross section and easy to clean scale characteristics.

[0003] The tube and shell heat exchanger is divided into tube side and shell side two parts, wherein the head structure has a great influence on the heat exchange process of the tube side structure. Unreasonable head structure may cause uneven flow between the tube bundles of the tube side, and then make the internal temperature field of the tube and shell heat exchanger unevenly distributed and the effective heat exchange area reduced, so that the actual working effect of the heat exchanger cannot reach the design target or even the operation requirement. Therefore, designing a reasonable tube and shell heat exchanger head structure to optimize and improve the flow characteristics of the fluid in the tube bundle of the tube side has always been the key research direction of the structure design of the tube and shell heat exchanger.

[0004] The research results show that an important reason affecting the performance of the tube and shell heat exchanger is that a large amount of vortex phenomenon occurs in the flow region of the flow direction change in the head, which causes the retention of part of the fluid, affects the heat exchange performance of the heat exchanger, and causes local resistance loss and uneven flow. SUMMARY

[0005] Therefore, the present application provides a tube and shell heat exchanger head and a tube and shell heat exchanger for improving the flow distribution characteristics of the flow region in the head, so as to meet the requirements of improving the local resistance loss and uniformity in the heat exchanger.

[0006] The technical scheme of the present application is as follows:

[0007] In a first aspect, the present application provides a tube and shell heat exchanger head, which comprises a tube plate, a cover and a partition plate, the cover is a curved shell structure, which is fixedly arranged on the tube plate, the cover and the tube plate form a flow cavity, the tube plate is provided with three mounting hole groups at intervals, each mounting hole group comprises a plurality of mounting holes, the mounting holes are used for fixing the tube bundle in the heat exchanger, the partition plate is arranged in the flow cavity, one end of the partition plate is fixedly connected with the inner wall of the cover, and the other end is fixedly connected with the tube plate, the partition plate divides the flow cavity into a single-pass cavity and a single-pass cavity, and the inclined direction of the partition plate is towards the two adjacent mounting hole groups, and the two adjacent mounting hole groups are located in the single-pass cavity.

[0008] On the basis of the above technical scheme, preferably, the cover is provided with a flow port, and the flow port is in communication with the single-pass cavity.

[0009] Preferably, the cover is a hemispherical or ellipsoidal shell structure.

[0010] Preferably, the middle mounting hole group of the three mounting hole groups is located at the center of the tube plate, and the two side mounting hole groups are symmetrically arranged relative to the middle mounting hole group.

[0011] As some embodiments, the partition plate is a straight plate, the lower end of the partition plate is fixedly connected with the tube plate between the adjacent two mounting hole groups, and the upper end of the partition plate is fixedly connected with the inner wall center of the cover.

[0012] As some other embodiments, the partition plate is an arc plate structure, the lower end of the partition plate is fixedly connected with the tube plate between the adjacent two mounting hole groups, the projection of the partition plate on the center symmetry plane of the cover is a quarter period segment of a sine function curve, the upper end of the partition plate is tangent to the projection contour of the cover at the top of the cover, and the relative arc direction of the partition plate is towards the stroke cavity.

[0013] Preferably, a coordinate system is established on the symmetric interface of the cover head, wherein the inner height of the cover is L, and the distance between the bottom end of the partition plate and the center of the cover head is d, and the projection curve of the partition plate on the center symmetry plane of the cover can be expressed as: x represents the horizontal position of the bottom end of the partition plate on the center symmetry plane of the cover, and y represents the height of the partition plate on the center symmetry plane of the cover.

[0014] In a second aspect, the present application provides a shell-and-tube heat exchanger, comprising a shell, a tube bundle group and the shell-and-tube heat exchanger cover head of the first aspect, the shell is internally provided with three tube bundle groups, the tube bundle group is composed of a plurality of tubes, the two ends of the shell are fixedly connected with the cover head, the two ends of the tube bundle group are correspondingly connected with the mounting hole groups on the tube plate, and the two ends of the shell in the axial direction are respectively provided with a heat exchange inlet and a heat exchange outlet.

[0015] Preferably, the cover head further comprises a ring-shaped end cover, the ring-shaped end cover is fixedly arranged on the outer circumferential side of the tube plate, and the ring-shaped end cover is fixedly connected with the opening end of the shell.

[0016] Compared with the prior art, the present application has the following beneficial effects:

[0017] (1) The inclined arrangement of the baffle changes the impact angle of the fluid flowing through the baffle, and the fluid no longer directly impacts the junction of the head and the baffle. This inclined arrangement guides the fluid to flow at a smoother angle, reducing the local resistance loss caused by direct impact. The inclined baffle effectively reduces the backflow phenomenon by changing the direction of fluid flow. The path of the fluid in the flow chamber is guided to be smoother, thereby reducing the stagnation area, improving the uniformity of fluid distribution, and stabilizing the flow of fluid in the transition chamber, thereby improving the heat exchange efficiency and overall performance of the heat exchanger.

[0018] (2) By arranging the baffle in an arc shape, the arc-shaped baffle effectively guides the flow of the tube bundle in the cavity formed by the arc-shaped baffle and the head, further weakening the direct impact of the tube bundle flow on the cavity formed by the arc-shaped baffle and the head and the backflow effect at the junction of the baffle and the head. The local resistance and flow uniformity of the cavity formed by the arc-shaped baffle and the head are further improved.

[0019] (3) By arranging the projection of the baffle on the center symmetry plane of the cover to be a quarter period segment of a sine function curve, the upper end of the baffle is tangent to the projection profile of the cover at the top of the cover, and the opposite arc-shaped direction of the baffle is towards the transition chamber. This specific arc-shaped design can guide the fluid to flow in a specific path in the heat exchanger, thereby improving the heat exchange efficiency and reducing the dead zone or vortex area. The shape of the sine function curve helps to smooth the flow path of the fluid, reducing the resistance encountered by the fluid during flow, thereby reducing pressure loss. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0021] Figure 1 A perspective view of the head of the shell-and-tube heat exchanger disclosed in the present application;

[0022] Figure 2 A structure of the baffle disclosed in the present application;

[0023] Figure 3 Another structure of the baffle disclosed in the present application;

[0024] Figure 4 A top view of the head of the shell-and-tube heat exchanger disclosed in the present application;

[0025] Figure 5 A Figure 4A-A plane cross-sectional view;

[0026] Figure 6 A head plan view disclosed by the present application;

[0027] Figure 7 A tube-shell heat exchanger exploded view disclosed by the present application;

[0028] Figure 8 A tube-shell heat exchanger plane structure view disclosed by the present application;

[0029] Figure 9 A Figure 8 B-B plane cross-sectional view;

[0030] Figure 10 A head flow field view under different baffle structures;

[0031] Reference signs:

[0032] 1, head; 11, tube sheet; 12, cover; 13, baffle; Q, flow cavity; Q1, exchange cavity; Q2, single-pass cavity; 121, flow port; 110, mounting hole group; 110a, mounting hole; 2, shell; 3, tube bundle group; 31, tube bundle; 21, heat exchange inlet; 22, heat exchange outlet; 14, annular end cover. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0034] As Figure 1 shown, in conjunction with Figure 2 and 3 , the present application discloses a tube-shell heat exchanger head 1, which comprises a tube sheet 11, a cover 12 and a baffle 13.

[0035] The tube sheet 11 is used to fix the tube bundle 31 inside the heat exchanger and forms part of the structure of the head 1. The tube sheet 11 is provided with a plurality of mounting hole groups 110, each of which comprises a plurality of mounting holes 110a for fixing the tube bundle 31. In the present embodiment, the shape of the tube sheet 11 is preferably disc-shaped, which is to adapt to the cylindrical tube-shell heat exchanger.

[0036] The cover 12 is a curved shell structure, which is fixed on the tube sheet 11 and cooperates with the tube sheet 11 to form a flow cavity Q. The curved shell design is conducive to the smooth flow of fluid and reduces flow dead angles.

[0037] The baffle plate 13 is arranged inside the head 1 and divides the flow cavity Q inside the head 1 into a pass-changing cavity Q1 and a single-pass cavity Q2. In this embodiment, the pass-changing cavity Q1 refers to the connection between two adjacent tube passes in the shell-and-tube heat exchanger through the pass-changing cavity Q1. The pass-changing cavity Q1 not only serves as a channel for fluid flow, but also transfers fluid between multiple tube passes, so that the fluid can circulate between different tube passes and exchange heat.

[0038] The single-pass cavity Q2 is connected to only one tube pass, which can be the inlet or outlet of the fluid, but is not connected to other tube passes. In other words, the single-pass cavity Q2 is an independent cavity, and the fluid only completes a single flow in this cavity.

[0039] In the prior art, the baffle plate 13 is mostly in a straight plate structure, that is, the baffle plate 13 is vertically connected to the inner wall of the tube plate 11 and the cover 12. For the head 1 with a straight baffle plate, on the one hand, the outflow of the tube bundle 31 has a direct impact on the pass-changing cavity Q1 formed by the straight baffle plate and the head 1, thereby causing a large local resistance loss; on the other hand, a large amount of backflow is easily generated in the pass-changing cavity Q1 formed by the straight baffle plate and the head 1 at the junction area of the straight baffle plate and the head 1, thereby forming a flow stagnation area and affecting the flow distribution of the tube bundle 31, resulting in uneven fluid distribution in the tube bundle 31 and affecting the heat exchange performance.

[0040] To solve the above problems, the baffle plate 13 is arranged in the flow cavity Q in an inclined manner in this embodiment. One end of the baffle plate 13 is fixedly connected to the inner wall of the cover 12, and the other end is fixedly connected to the tube plate 11. The baffle plate 13 divides the flow cavity Q into the pass-changing cavity Q1 and the single-pass cavity Q2. The inclination direction of the baffle plate 13 is toward the two adjacent mounting hole groups 110, and the two adjacent mounting hole groups 110 are located in the pass-changing cavity Q1.

[0041] With the above technical solution, the inclined arrangement of the baffle plate 13 changes the impact angle of the fluid flowing through the baffle plate 13, and the fluid no longer directly impacts the junction of the head 1 and the baffle plate 13. This inclined arrangement guides the fluid to flow at a smoother angle, reducing the local resistance loss caused by direct impact. The inclined baffle plate 13 effectively reduces the backflow phenomenon by changing the flow direction of the fluid, and the path of the fluid in the flow cavity Q is guided to be smoother, thereby reducing the stagnation area.

[0042] The design of the inclined baffle plate 13 optimizes the fluid flow path in the pass-changing cavity Q1, reduces the local resistance loss and the backflow phenomenon, and improves the uniformity of fluid distribution. The fluid flows more stably in the pass-changing cavity Q1, thereby improving the heat exchange efficiency and overall performance of the heat exchanger. The structural arrangement of the baffle plate 13 not only reduces the flow stagnation area, but also makes the fluid flow between the tube bundles 31 more uniform, significantly improving the heat exchange effect.

[0043] In some preferred embodiments, the cover 12 is provided with a flow port 121, which communicates with the one-way cavity Q2. The flow port 121 acts as a fluid channel, allowing fluid to enter or exit the one-way cavity Q2 from outside the cover 1. This provides a clear path for the fluid's entry and exit, ensuring that the fluid can effectively flow into the one-way cavity Q2. The flow port 121 can be either an inlet or an outlet. Specifically, in a three-pass shell-and-tube heat exchanger, which requires two covers 1, the flow port 121 on one cover 1 is the inlet, and the flow port 121 on the other cover 1 is the outlet.

[0044] In some preferred embodiments, the cover 12 is a hemispherical or ellipsoidal shell 2 structure. This structural arrangement allows the fluid to flow more smoothly when entering the flow cavity Q, reducing localized impacts and turbulence, thereby lowering localized resistance losses.

[0045] In this embodiment, the middle mounting hole group 110 of the three mounting hole groups 110 is located at the center of the tube sheet 11, and the mounting hole groups 110 on both sides are symmetrically arranged relative to the middle mounting hole group 110. The middle mounting hole group 110 being located at the center of the tube sheet 11 ensures that fluid can enter or exit uniformly from the center, minimizing fluid deviation within the heat exchanger and guaranteeing uniform fluid distribution throughout the heat exchanger. The symmetrical arrangement of the two mounting hole groups 110 relative to the middle mounting hole group 110 makes the fluid flow more balanced, avoiding unbalanced flow paths within the shell 2, and further reducing local resistance and eddies.

[0046] As one implementation method, refer to the appendix. Figure 2 As shown, the partition 13 is a straight plate with an incline. In this embodiment, the shape of the partition 13 can be understood as an inclined partition. The lower end of the partition 13 is fixedly connected to the tube plate 11 between two adjacent mounting hole groups 110, and the upper end of the partition 13 is fixedly connected to the center of the inner wall of the cover 12.

[0047] To address the issue of excessive backflow and flow stagnation in head 1 with straight diaphragms, inclined diaphragms are used to directly eliminate these areas. Furthermore, the inclined diaphragms also guide the flow in the tube bundle 31 within the transition cavity Q1 formed by the inclined diaphragms and head 1, thus reducing the local resistance and improving flow uniformity in this cavity. Numerical results show that compared to the cavity formed by straight diaphragms and head 1, the local pressure drop in the cavity formed by inclined diaphragms and head 1 is reduced by approximately 10%, while the local flow uniformity is improved by approximately 7%.

[0048] As another implementation method, refer to the appendix. Figures 3-6 As shown, the partition 13 is an arc-shaped plate structure. The lower end of the partition 13 is fixedly connected to the tube plate 11 between two adjacent mounting hole groups 110. The projection of the partition 13 on the central symmetry plane of the cover 12 is a quarter period segment of a sine function curve. The upper end of the partition 13 is tangent to the projection outline of the cover 12 at the top of the cover 12. The relative arc direction of the partition 13 is towards the switching cavity Q1.

[0049] Based on the optimization of the inclined baffle, and considering that the inclined baffle has limited guiding effect on the flow from tube bundle 31, an arc-shaped baffle 13 is used instead to more effectively guide the flow from tube bundle 31 into the cavity formed by the arc-shaped baffle 13 and the end cap 1. This further weakens the direct impact of the flow from tube bundle 31 on the cavity formed by the arc-shaped baffle 13 and the end cap 1, as well as the backflow effect at the interface between the baffle 13 and the end cap 1. This results in further improvement in the local resistance and flow uniformity of the cavity formed by the arc-shaped baffle 13 and the end cap 1. (See attached...) Figure 10 As shown, numerical results indicate that compared to the cavity formed by the inclined diaphragm and the end cap 1, the local pressure drop in the cavity region formed by the arc-shaped diaphragm 13 and the end cap 1 is reduced by a maximum of about 15%, while the local flow uniformity is improved by a maximum of about 4%.

[0050] To ensure that the baffle 13 meets specific design requirements and achieves optimal hydrodynamic performance and heat exchange efficiency, this embodiment establishes a coordinate system on the symmetrical interface of the head 1, where the height inside the cover 12 is L, and the distance from the bottom of the baffle 13 to the center of the head 1 is d. The projection curve of the baffle 13 on the symmetrical plane of the cover 12 can then be expressed as: x represents the horizontal position of the bottom end of the partition 13 on the central symmetry plane of the cover 12, and y represents the height of the partition 13 on the central symmetry plane of the cover 12.

[0051] The above equations clarify the projection curve of the baffle 13 on the symmetry plane of the head 1, thus defining the arcuate profile of the baffle 13. The height L inside the cover 12 is known, and the distance d from the bottom of the baffle 13 to the center of the head 1 is also a predetermined parameter in the design, set according to the dimensions and design requirements of the head 1. The coordinate values ​​of the baffle 13 in the horizontal position are as follows: x is a known value selected between [-d, 0], and y is calculated using the equations based on the known L, d, and given x values. Through this curve equation, the geometry of the baffle 13, the height distribution at each point, the positions of its bottom and top ends, and its tangent relationship with the top of the cover 12 can be determined, thereby achieving the design objectives of optimizing the fluid flow path, reducing pressure loss, uniformly distributing fluid, and improving structural stability.

[0052] By employing a specific arc design, fluid can be guided to flow along a designated path within the heat exchanger, thereby improving heat exchange efficiency and reducing dead zones or vortex regions. The shape of the sine function curve helps to smooth the fluid flow path, reducing the resistance encountered by the fluid during flow and thus lowering pressure loss.

[0053] The present invention also discloses a shell-and-tube heat exchanger, as shown in the attached figure. Figures 7-9 As shown, the device includes a shell 2, a tube bundle assembly 3, and a shell-and-tube heat exchanger head 1 disclosed in the above embodiment. Three tube bundle assemblies 3 are provided inside the shell 2. Each tube bundle assembly 3 is composed of multiple tube bundles 3. Both ends of the shell 2 are fixedly connected to the head 1, and both ends of the tube bundle assembly 3 are respectively connected to the mounting hole assembly 110 on the tube sheet 11. Heat exchange inlet 21 and heat exchange outlet 22 are respectively provided at both ends of the shell 2 in the axial direction.

[0054] The heat exchanger is internally equipped with three tube bundles 3, enabling a three-pass structure that increases the heat exchange area and improves heat exchange efficiency. Simultaneously, the fluid passes through two end caps 1 between the three tube passes, allowing for sufficient heat exchange between the different tube bundles 3, thus enhancing overall heat exchange performance. The inclined or arc-shaped baffles 13 within the end caps 1 effectively guide fluid flow, ensuring more uniform flow within the heat exchanger. This design helps prevent localized stagnation or eddies within the heat exchanger, further improving heat exchange efficiency and fluid distribution. The inclined or arc-shaped baffles 13 also reduce localized resistance losses during fluid flow, optimizing the flow path and allowing for smoother fluid flow throughout the heat exchanger, further enhancing its overall performance.

[0055] The heat exchanger disclosed in this embodiment, through a three-pass tube structure combined with two end caps 1 and an inclined baffle 13, achieves effective heat exchange between multiple tube bundles 3, optimizes the uniformity of fluid flow, and reduces local resistance losses. This structural design not only improves heat exchange efficiency but also enhances the stability and performance of the heat exchanger, enabling it to exhibit higher efficiency and better fluid flow characteristics in practical applications.

[0056] In some embodiments, the end cap 1 further includes an annular end cap 14, which is fixedly disposed on the outer periphery of the tube sheet 11 and is fixedly connected to the open end of the housing 2. The annular end cap 14 facilitates fixation to the open end of the housing 2 via a flange.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A shell-and-tube heat exchanger head, characterized by: The head (1) comprises a tube sheet (11), a cover (12) and a partition plate (13), the cover (12) is a curved shell structure, which is fixedly arranged on the tube sheet (11), the cover (12) and the tube sheet (11) form a flow cavity (Q), the tube sheet (11) is provided with three mounting hole groups (110) at intervals, each mounting hole group (110) comprises a plurality of mounting holes (110a), the mounting holes (110a) are used for fixing the tube bundle (31) in the heat exchanger, the partition plate (13) is arranged in the flow cavity (Q) and is inclined, one end of the partition plate (13) is fixedly connected with the inner wall of the cover (12), and the other end is fixedly connected with the tube sheet (11), the partition plate (13) divides the flow cavity (Q) into a cycle cavity (Q1) and a single-pass cavity (Q2), and the inclined direction of the partition plate (13) is towards the adjacent two mounting hole groups (110), and the adjacent two mounting hole groups (110) are located in the cycle cavity (Q1); The partition plate (13) is an arc-shaped plate structure, the lower end of the partition plate (13) is fixedly connected with the tube sheet (11) between the adjacent two mounting hole groups (110), the projection of the partition plate (13) on the center symmetry plane of the cover (12) is a quarter period segment of a sine function curve, the upper end of the partition plate (13) is tangent to the projection contour of the cover (12) at the top of the cover (12), and the relative arc-shaped direction of the partition plate (13) is towards the cycle cavity (Q1); A coordinate system is established on the symmetry interface of the head (1), wherein the height of the cover (12) is L, and the distance from the bottom end of the partition plate (13) to the center of the head (1) is d, and the projection curve of the partition plate (13) on the center symmetry plane of the cover (12) is represented as: , x represents the horizontal position of the bottom end of the partition plate (13) on the center symmetry plane of the cover (12), and y represents the height of the partition plate (13) on the center symmetry plane of the cover (12).

2. The shell-and-tube heat exchanger head of claim 1, wherein: The cover (12) is provided with a flow port (121), and the flow port (121) and the single-pass cavity (Q2) are communicated.

3. The shell-and-tube heat exchanger head of claim 2, wherein: The cover (12) is a hemispherical or ellipsoidal shell structure.

4. The shell-and-tube heat exchanger head of claim 3, wherein: The mounting hole group (110) in the middle of the three mounting hole groups (110) is located at the center position of the tube sheet (11), and the mounting hole groups (110) on both sides are symmetrically arranged relative to the mounting hole group (110) in the middle.

5. A shell-and-tube heat exchanger comprising a shell (2), a tube bundle group (3) and a shell-and-tube heat exchanger head according to any one of claims 1 to 4, characterized in that: The shell (2) is provided with three tube bundle groups (3) inside, the tube bundle group (3) is composed of a plurality of tube bundles (31), the two ends of the shell (2) are fixedly connected with the head (1) respectively, the two ends of the tube bundle group (3) are correspondingly connected with the mounting hole groups (110) on the tube sheet (11) respectively, and the heat exchange inlet (21) and the heat exchange outlet (22) are arranged at the two ends of the shell (2) in the axial direction respectively.

6. The shell and tube heat exchanger as claimed in claim 5, wherein, The head (1) further comprises an annular end cover (14), the annular end cover (14) is fixedly arranged on the outer circumferential side of the tube sheet (11), and the annular end cover (14) is fixedly connected with the opening end of the shell (2).

Images