Flow distribution device for shell and tube heat exchanger

Abstract

The invention discloses a flow distribution device for a shell-and-tube heat exchanger, which relates to the field of shell-and-tube heat exchangers, and comprises a bell and spigot, a distribution cylinder and a distribution ring, the distribution cylinder is of a hollow structure with an opening in the upper end, the bell and spigot is fixedly connected to the upper end of the distribution cylinder, and the distribution cylinder is communicated with an inlet of the end socket through the bell and spigot; a plurality of circles of first distribution holes are formed around the side wall of the distribution cylinder up and down, and the sizes of the first distribution holes are sequentially reduced from top to bottom; a plurality of circles of second distribution holes are concentrically formed in the bottom of the distribution cylinder, and the sizes of the second distribution holes are sequentially reduced from outside to inside; the distribution ring is coaxially arranged below the distribution cylinder, and a plurality of circles of third distribution holes which are concentrically arranged are formed in the distribution ring. The heat exchange tube has the advantages that fluid can uniformly enter the heat exchange tube, and the heat exchange tube is convenient to process and use.

Description

Technical Field

[0001] The invention relates to the field of shell and tube heat exchangers, and in particular to a flow distribution device for shell and tube heat exchangers. Background Art

[0002] Shell and tube heat exchangers, especially when there is gas-liquid two-phase flow in the tube-side heat exchange, often have uneven liquid distribution. The liquid flow in some heat exchange tubes is large, while the other part of the heat exchange tubes is easily short-circuited, which will lead to a low overall heat transfer coefficient of the heat exchanger, resulting in the need for a larger heat exchange area, resulting in low economy and space utilization.

[0003] Patent document with publication number CN114963840A discloses a Coanda flow guide head for a plate heat exchanger, the shape of the head shell and the shape of the layered guide plate are based on the Coanda effect, so that the fluid working medium flows to the core channel of the heat exchanger by itself. The shape of the guide plate of the existing flow distribution device needs to be processed according to a specific curve, the shape is complex and the number is large, and the processing is difficult; and only special guide heads can be used, and the shell and tube heat exchanger with an existing head cannot be modified, and the versatility is poor. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to make the fluid enter the heat exchange tube more evenly to facilitate processing and use.

[0005] The present invention solves the above-mentioned technical problems through the following technical means: a flow distribution device for a shell and tube heat exchanger, comprising a socket, a distribution tube and a distribution ring; the distribution tube is a hollow structure with an opening at the upper end, the socket is fixedly connected to the upper end of the distribution tube, and the distribution tube is connected to the inlet of the head through the socket; multiple circles of first distribution holes are arranged up and down around the side wall of the distribution tube, and the size of the first distribution holes decreases from top to bottom; multiple circles of second distribution holes are concentrically arranged at the bottom of the distribution tube, and the size of the second distribution holes decreases from outside to inside; the distribution ring is coaxially arranged below the distribution tube, and the distribution ring is provided with multiple circles of third distribution holes arranged concentrically.

[0006] As an optimized technical solution, the inner angles of the first distribution hole and the second distribution hole are both arc chamfered, so as to reduce the pressure loss as much as possible.

[0007] As an optimized technical solution, the sum of the opening areas of the first distribution hole and the second distribution hole is consistent with the area of ​​the inlet of the distribution cylinder, so as to ensure that the flow rate is basically consistent.

[0008] As an optimized technical solution, the first distribution holes are rectangular, the second distribution holes in the innermost circle are triangular, and the second distribution holes in the remaining circles are elliptical.

[0009] As an optimized technical solution, the radial widths of the third distribution holes are equal.

[0010] As an optimized technical solution, the distribution ring includes a plurality of concentric circular rings with different diameters, the radius difference of each circular ring is equal, and the third distribution hole is formed between adjacent circular rings.

[0011] As an optimized technical solution, the outer diameter of the distribution ring is 2 / 5 to 3 / 5 of the radius of the heat exchanger tube sheet.

[0012] As an optimized technical solution, the distance between the distribution ring and the tube sheet of the heat exchanger is 1 / 5R to 1 / 3R, where R is the radius of the tube sheet.

[0013] As an optimized technical solution, the flow distribution device for the shell and tube heat exchanger further includes a support seat, and the support seat is fixedly connected between the distribution cylinder and the distribution ring.

[0014] As an optimized technical solution, the support seat includes a plurality of right-angled trapezoidal support plates, each of which is evenly arranged in a circle and fixedly connected together at the center.

[0015] The advantages of the present invention are as follows: the flow of materials before entering the tube side of the shell and tube heat exchanger is distributed by the distribution cylinder and the distribution ring, so that the fluid can enter the heat exchange tube more evenly; the opening of the first distribution hole and the second distribution hole follows the principle of first large and then small from top to bottom and from outside to inside, which is conducive to the fluid entering the outer ring of the tube plate, which is conducive to heat exchange, increases the heat exchange coefficient, and improves the heat exchange efficiency; the distribution ring plays a distribution and turbulence role, causing the fluid to sputter and improve the effect of uniform distribution; the structure is simple, and it is convenient to process and use; the shell and tube heat exchanger with an existing head can be modified by designing a socket of a suitable size, and it has good versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is an axonometric schematic diagram of a flow distribution device for a shell and tube heat exchanger according to an embodiment of the present invention installed in a head.

[0017] Figure 2 It is an axonometric schematic diagram of a flow distribution device for a shell and tube heat exchanger according to an embodiment of the present invention.

[0018] Figure 3 It is a bottom view schematically showing a dispensing cartridge according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0020] like Figures 1 to 3 As shown, an embodiment of the present invention discloses a flow distribution device for a shell and tube heat exchanger, comprising a socket 1, a distribution cylinder 2, a support seat 3 and a distribution ring 4.

[0021] The socket 1 is used to be inserted into the inner side of the inlet of the head 5 to play a fixing role.

[0022] The distribution tube 2 is used to distribute the flow. The distribution tube 2 is a hollow cylinder with an open upper end. The socket 1 is welded to the upper end of the distribution tube 2. The distribution tube 2 is connected to the inlet of the head 5 through the socket 1.

[0023] There are multiple circles of first distribution holes 21 arranged up and down around the side wall of the distribution tube 2, and each circle of multiple first distribution holes 21 is evenly distributed along the circumferential direction, and the size of the first distribution holes 21 decreases from top to bottom; there are multiple circles of second distribution holes 22 concentrically arranged at the bottom of the distribution tube 2, and each circle of multiple second distribution holes 22 is evenly distributed along the circumferential direction, and the size of the second distribution holes 22 decreases from outside to inside; the openings of the first distribution holes 21 and the second distribution holes 22 follow the principle of first large and then small from top to bottom and from outside to inside, which is conducive to the fluid entering the outer circle of the tube plate and facilitating heat exchange.

[0024] The first distribution holes 21 are rectangular, the innermost circle of second distribution holes 22 are triangular, and the remaining circles of second distribution holes 22 are elliptical. The inner angles of the first distribution holes 21 and the second distribution holes 22 are smooth arc chamfers, which can minimize pressure loss.

[0025] The sum of the opening areas of the first distribution hole 21 and the second distribution hole 22 is substantially consistent with the area of ​​the inlet of the distribution tube 2, thereby ensuring that the flow rate is substantially consistent.

[0026] The support seat 3 is welded between the distribution barrel 2 and the distribution ring 4 for connecting the distribution barrel 2 and the distribution ring 3. The support seat 3 includes four right-angled trapezoidal support plates, each of which is evenly surrounded in a circle and the central part is welded together.

[0027] The distribution ring 4 is coaxially arranged below the distribution cylinder 2. The distribution ring 4 includes a plurality of concentric circular rings with different diameters. The radius difference of each circular ring is equal. A third distribution hole 41 is formed between adjacent circular rings, thereby forming a plurality of circles of third distribution holes 41 which are concentrically arranged and have equal radial widths. The outer diameter of the distribution ring 4 is 2 / 5 to 3 / 5 of the radius of the heat exchanger tube sheet. The distance between the distribution ring 4 and the heat exchanger tube sheet depends on the flow rate and the radius R of the tube sheet. Under normal circumstances, the more suitable distance is 1 / 5R to 1 / 3R.

[0028] Working principle: If the distribution device is not used, after the fluid enters the inlet of the head 5, most of the fluid will flow directly into the heat exchange tube in the center along the axial diameter of the inlet, resulting in a situation where the flow rate is less in the outer circle and more in the inner circle. The number of heat exchange tubes in the outer circle of the shell and tube heat exchanger is large. When heat is exchanged through the outer circle tubes, the heat transfer coefficient is larger and the heat transfer efficiency is higher. By arranging the flow distribution device for the shell and tube heat exchanger in the embodiment of the present invention, after the fluid enters the inlet of the head 5, it passes through the distribution tube 2 and is sprayed along the radial direction of the distribution tube 2. More fluid flows out from the upper part of the first distribution hole 21 at the top and the second distribution hole 22 of the outer circle, and less fluid flows out from the upper part of the first distribution hole 21 at the bottom and the second distribution hole 22 of the inner circle. This is consistent with expectations, that is, the outer circle heat exchange tube obtains more fluid, and the inner circle heat exchange tube obtains less fluid. The distribution ring 4 also plays a distribution role. When the fluid falls on the distribution ring 4, the distribution ring 4 will play a turbulent role, causing the fluid to sputter, thereby improving the effect of uniform distribution.

[0029] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A flow distribution device for a shell and tube heat exchanger, characterized in that: It includes a socket, a distribution tube and a distribution ring; the distribution tube is a hollow structure with an opening at the upper end, the socket is fixedly connected to the upper end of the distribution tube, and the distribution tube is connected to the entrance of the head through the socket; multiple circles of first distribution holes are arranged up and down around the side wall of the distribution tube, and the size of the first distribution holes decreases from top to bottom; multiple circles of second distribution holes are concentrically arranged at the bottom of the distribution tube, and the size of the second distribution holes decreases from outside to inside; the distribution ring is coaxially arranged below the distribution tube, and the distribution ring is provided with multiple circles of third distribution holes arranged concentrically.

2. The flow distribution device for a shell and tube heat exchanger according to claim 1, characterized in that: The inner angles of the first distribution hole and the second distribution hole are both arc chamfers.

3. The flow distribution device for a shell and tube heat exchanger according to claim 1, characterized in that: The sum of the opening areas of the first distribution hole and the second distribution hole is consistent with the area of ​​the inlet of the distribution cylinder.

4. The flow distribution device for a shell and tube heat exchanger according to claim 1, characterized in that: The first distribution holes are rectangular, the innermost circle of second distribution holes are triangular, and the remaining circles of second distribution holes are elliptical.

5. The flow distribution device for shell and tube heat exchanger according to claim 1, characterized in that: The radial widths of the third distribution holes are equal.

6. The flow distribution device for a shell and tube heat exchanger according to claim 5, characterized in that: The distribution ring includes a plurality of concentric circular rings with different diameters, the radius difference of each circular ring is equal, and the third distribution hole is formed between adjacent circular rings.

7. The flow distribution device for a shell and tube heat exchanger according to claim 1, characterized in that: The outer diameter of the distribution ring is 2 / 5 to 3 / 5 of the radius of the heat exchanger tube sheet.

8. The flow distribution device for a shell and tube heat exchanger according to claim 1, characterized in that: The distance between the distribution ring and the tube sheet of the heat exchanger is 1 / 5R to 1 / 3R, where R is the radius of the tube sheet.

9. The flow distribution device for a shell and tube heat exchanger according to claim 1, characterized in that: The flow distribution device for the shell and tube heat exchanger further comprises a support seat, and the support seat is fixedly connected between the distribution cylinder and the distribution ring.

10. The flow distribution device for a shell and tube heat exchanger according to claim 9, characterized in that: The support seat comprises a plurality of right-angled trapezoidal support plates, each of which is evenly arranged in a circle and fixedly connected together at the center.

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