Helical corrugated pipe wall-attached jet flow shell-and-tube heat exchanger

Abstract

The invention discloses a spiral corrugated pipe wall-attached jet shell-and-tube heat exchanger which comprises a shell, a spiral corrugated pipe, an arch-shaped baffle plate, a tube plate, an end socket, a tube pass inlet and outlet connecting pipe and a shell pass inlet and outlet connecting pipe. Pipe side fluid enters the spiral corrugated pipe through the pipe pass inlet connecting pipe, centrifugal force caused by the spiral corrugated structure can enable the fluid in the pipe to generate harmonious and ordered vortex and secondary flow, the flowing state of the fluid in the pipe is changed, and therefore the purpose of enhancing pipe side heat exchange is achieved. Shell side fluid enters the snake-shaped channel formed by the multiple arch-shaped baffle plates through the shell side inlet connecting pipe, the flowing heat exchange time of the shell side fluid is prolonged, part of the fluid flows through holes formed by the spiral corrugated pipes and the arch-shaped baffle plates, wall-attached rotating jet flow is generated, and shell side heat transfer is enhanced. According to the shell-and-tube heat exchanger, the problems of flowing dead zones and backflow of shell pass fluid of the shell-and-tube heat exchanger can be solved, meanwhile, the flowing state of the shell pass fluid and the flowing state of tube pass fluid are improved, and the heat exchange capacity of the shell-and-tube heat exchanger is improved.

Description

Technical Field

[0001] The invention belongs to the field of shell and tube heat exchangers, and in particular relates to a spiral corrugated tube wall-attached jet shell and tube heat exchanger. Background Art

[0002] The shell and tube heat exchanger is mainly composed of shell, head, tube sheet, arched baffle, heat exchange tube and other components. It has the advantages of simple structure, high reliability, strong adaptability and easy maintenance. It is widely used in many industrial fields such as electricity and energy. The flow state of shell-side fluid and tube-side fluid is an important factor affecting the heat transfer performance of shell and tube heat exchanger. In practical applications, the "S"-shaped channel formed by the baffle will cause huge pressure loss, and the shell-side fluid will have flow dead zone and reflux phenomenon, resulting in low heat transfer efficiency of shell and tube heat exchanger and easy scaling in flow dead zone. Invention patent CN107747881A designs a shell and tube heat exchanger with a full circular support plate with square tube holes. The shell side fluid passes through the gap between the square hole and the round tube to generate a jet, which can effectively avoid scaling, but the overall flow is longitudinal, the process is reduced, the heat exchange is insufficient, and the heat exchange efficiency of the heat exchanger is not high. Invention patent CN22041879U uses an arched plate with small holes to transform the transverse flow of the fluid in the shell side of the heat exchanger into a mixed flow, reducing the dead zone of the flow, but the heat transfer efficiency of the fluid passing through the small holes is low. Invention patent CN22041878U uses an arched baffle with plum blossom holes, and the tube bundle can pass through the plum blossom holes to improve the defects of the arched plate with small holes, taking into account both improving the heat transfer efficiency and reducing the dead zone of the flow, but the enhanced heat transfer is limited to the shell side, and the heat transfer efficiency is not significantly improved. Summary of the invention

[0003] The object of the present invention is to provide a spiral corrugated tube wall-mounted jet shell and tube heat exchanger to solve the flow dead zone and backflow problems that are easy to occur in the shell-side fluid of the shell and tube heat exchanger, while improving the flow state of the shell-side fluid and the tube-side fluid, thereby improving the heat exchange capacity of the shell and tube heat exchanger.

[0004] To achieve the above object, the technical solution adopted by the present invention is: a spiral corrugated tube wall jet shell and tube heat exchanger, comprising a shell, a shell side inlet pipe, a shell side outlet pipe and a head, the shell side inlet pipe is arranged at the upper right end, the shell side outlet pipe is arranged at the lower left end, the shell side is provided with a head and a tube sheet on both sides, and a plurality of arched baffles and spiral corrugated tubes are arranged inside the shell; A left-side head baffle is arranged inside the head on the left side of the shell, and the left-side head baffle cooperates with the left-side tube sheet to separate the left-side head into three or more converging chambers, and at the same time, a tube-side inlet pipe is arranged at the upper end of the left-side head, and a tube-side outlet pipe is arranged at the lower end, wherein the tube-side inlet pipe is connected to the uppermost converging chamber, and the tube-side outlet pipe is connected to the lowermost converging chamber; A right-side head baffle is arranged inside the head on the right side of the shell, and the right-side head baffle cooperates with the right-side tube sheet to separate the right-side head into two or more converging chambers; The tube sheet is provided with a plurality of tube sheet side wall tube holes, and the tube sheet side wall tube holes are connected and communicated with the ends of the spiral corrugated tube; The arcuate baffle is provided with a plurality of arcuate baffle side wall tube holes, and the spiral corrugated tube passes through the arcuate baffle side wall tube holes.

[0005] Furthermore, the shell-side inlet pipe, shell-side outlet pipe and bow-shaped baffle are welded to the shell, and the tube-side inlet pipe, tube-side outlet pipe and head are welded to each other.

[0006] Furthermore, the left-side head baffle plate, the right-side head baffle plate and the head are integrally cast and connected with the tube sheet to form a fluid confluence chamber.

[0007] Furthermore, two left-side head baffles are provided, and the two left-side head baffles separate the inside of the left head into three fluid converging chambers; and one right-side head baffle is provided, and the one right-side head baffle separates the inside of the right head into two fluid converging chambers.

[0008] Furthermore, the three fluid converging chambers separated in the left head are respectively the upper converging chamber on the left, the middle converging chamber on the left and the lower converging chamber on the left, and the two fluid converging chambers separated in the right head are respectively the upper converging chamber on the right and the lower converging chamber on the right, wherein the upper converging chamber on the left is connected with the pipe inlet connecting pipe, the lower converging chamber on the left is connected with the pipe outlet connecting pipe, the upper converging chamber on the right is connected with the upper converging chamber on the left and the middle converging chamber on the left through a spiral bellows, and the lower converging chamber on the right is connected with the middle converging chamber on the left and the lower converging chamber on the left through a spiral bellows.

[0009] Furthermore, the wall thickness and diameter of the head are the same as those of the shell.

[0010] Furthermore, a plurality of arched baffles are arranged alternately up and down, and form an S-shaped channel with the shell.

[0011] Furthermore, straight pipe sections with the same diameter as the tube sheet side wall and a length equal to the tube sheet wall thickness are reserved at both ends of the spiral corrugated pipe, and the spiral corrugated pipe is connected to the tube sheet and the side wall of the arched baffle by expansion connection.

[0012] Furthermore, the spiral bellows is an eight-head spiral bellows.

[0013] Compared with the prior art, the present invention has the following beneficial effects: The heat exchange tube of the present invention adopts an eight-head spiral corrugated tube. When the shell-side fluid flows through the periodically changing spiral corrugated structure, the centrifugal force caused by the spiral curved surface causes the fluid to produce harmonious and orderly vortices and secondary flows, increasing the fluid disturbance near the tube wall. The fluid separation and remixing between the crests and troughs of the spiral corrugated structure contribute to the fluid disturbance in the pipeline. In addition, the corrugated structure of the eight-head spiral corrugated tube increases the heat transfer area compared to the circular tube. Therefore, the use of the eight-head spiral corrugated tube effectively improves the heat transfer coefficient on both sides of the tube.

[0014] The baffles of the present invention are arranged in a staggered manner to form an "S"-shaped channel with the shell, and there are spiral pores between the eight-head spiral corrugated tube and the arched baffle tube hole. In the "S"-shaped channel, the fluid flows horizontally in the vertical tube bundle, which increases the flow and heat exchange time of the shell-side fluid. Part of the fluid flows through the pores formed by the eight-head spiral corrugated tube and the arched baffle tube hole, generating a wall-attached rotating jet, which can increase fluid disturbance and effectively reduce the flow dead zone on the one hand, and on the other hand, the longitudinal flow and the transverse flow are superimposed and transformed into a mixed flow, and finally the shell-side heat exchange is enhanced. .

[0015] Furthermore, the special structure of the spiral corrugated tube cooperates with the bow-shaped baffle, which can not only fix the tube bundle, but also cause the shell-side fluid to produce a wall-attached rotating jet, thereby achieving the purpose of enhancing heat transfer in the shell side.

[0016] Furthermore, the head, tube sheet and shell are connected by bolts and sealed by gaskets, avoiding the potential leakage risk caused by a large amount of welding, and at the same time avoiding the leakage and corrosion risks caused by welding points in the existing heat exchanger structure.

[0017] Furthermore, the present invention adopts a countercurrent heat exchange method, which increases the average heat exchange temperature difference compared with the cocurrent heat exchange method. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic cross-sectional view of the overall structure of the present invention; Figure 3 It is a schematic diagram of the component structure of the present invention; Figure 4 It is a structural diagram of the cooling mechanism of the present invention; Figure 5 It is a partial enlarged view of the spiral bellows of the present invention; Figure 6 This is a Nusselt number curve diagram of the eight-head spiral bellows of the present invention.

[0019] Reference numerals: 1. Shell; 101. Shell side inlet pipe; 102. Shell side outlet pipe; 2. Head; 201. Left head baffle; 202. Right head baffle; 203. Pipe inlet pipe; 204. Pipe outlet pipe; 3. Tube sheet; 301. Tube hole on the side wall of the tube sheet; 4. Arched baffle; 401. Tube hole on the side wall of the arched baffle; 5. Eight-head spiral corrugated pipe; 501. Eight-head spiral corrugated pipe straight pipe section. DETAILED DESCRIPTION

[0020] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] See also Figure 1-5 A spiral corrugated tube wall-mounted jet shell and tube heat exchanger comprises a shell 1, a shell-side inlet pipe 101 is arranged at the upper right end of the shell 1, and the shell-side fluid enters the shell 1 through the shell-side inlet pipe 101, a shell-side outlet pipe 102 is arranged at the lower left end of the shell 1, and the shell-side fluid is discharged from the shell 1 through the shell-side outlet pipe 102, a plurality of arched baffles 4 and eight-head spiral corrugated tubes 5 are arranged inside the shell 1, and a head 2 and a tube sheet 3 are arranged at both ends of the shell 1.

[0022] See also Figure 2-4 A plurality of arcuate baffles 4 are staggered and fixed inside the shell 1 to form an S-shaped channel. The shell side fluid flows inside the shell 1 along the serpentine channel. A plurality of tube holes 401 are opened on the side walls of the arcuate baffles 4.

[0023] See also Figure 3 A plurality of tube holes 301 are provided on the side wall of the tube sheet 3.

[0024] See also Figure 2-4 At both ends of several eight-head spiral bellows 5, straight pipe sections 501 of eight-head spiral bellows with the same diameter as the side wall of the tube sheet and a length equal to the wall thickness of the tube sheet are reserved. The tube sheet 3 and the straight pipe sections 501 of the eight-head spiral bellows are expanded to play a sealing and supporting role. The eight-head spiral bellows 5 and the arched baffle tube holes 401 are expanded to also play a supporting role. In addition, the gaps between the eight-head spiral bellows 5 and the arched baffle tube holes 401 allow part of the shell-side fluid to produce a wall-adhering rotating jet.

[0025] See also Figure 1-4The head 2, the tube sheet 3 and the shell are connected by bolts, and sealing gaskets are provided between the head 2, the tube sheet 3 and the shell. A left head baffle 201 is provided inside the left head 2, and cooperates with the tube sheet 3 to form three tube-side fluid confluence chambers. A right head baffle 202 is provided inside the right head 2, and cooperates with the tube sheet 3 to form two tube-side fluid confluence chambers. A tube-side inlet pipe 203 is provided at the upper end of the left head 2, and the tube-side fluid flows into the left head 2 from the tube-side inlet pipe 203. A tube-side outlet pipe 204 is provided at the lower end of the left head 2, and the tube-side fluid flows out of the left head 2 from the tube-side outlet pipe 204.

[0026] See also Figure 6 The heat transfer coefficient of the eight-head spiral corrugated tube selected by the present invention is 2.8-3.1 times that of the round tube. The data comes from Flow and Heat Transfer Mechanism and Optimization Design of Spirally Corrugated Tubes (2024, 16: 101001-11) published by Pan et al. in the Journal of Thermal Science and Engineering Applications. Single-head to eight-head spiral corrugated tubes were designed, and their flow and heat transfer performance in the tubes were studied. It was found that the eight-head spiral corrugated tube has the best heat transfer performance.

[0027] Working principle of this heat exchanger: When the shell and tube heat exchanger is in use, the low-temperature fluid on the shell side enters the shell 1 from the shell side inlet pipe 101, flows along the "S"-shaped channel formed by the arched baffle 1, and laterally flushes the eight-head spiral bellows 5. Part of the low-temperature fluid on the shell side flows through the pores formed by the arched baffle tube hole 401 and the eight-head spiral bellows 5, forming a wall-attached rotating jet. At the same time, the high-temperature fluid on the tube side enters the upper chamber of the left head 2 from the tube side inlet pipe 203, and flows into the eight-head spiral bellows 5 connected to the upper chamber of the left head 2 and the upper chamber of the right head 2 in turn. chamber, the eight-head spiral bellows 5 connected to the upper chamber of the right head 2, the middle chamber of the left head 2, the eight-head spiral bellows 5 connected to the middle chamber of the left head 2, the lower chamber of the right head 2, the eight-head spiral bellows 5 connected to the lower chamber of the right head 2, and the lower chamber of the left head 2. Convection heat exchange is carried out on the inside and outside of the eight-head spiral bellows 5 to achieve the purpose of reducing the shell-side fluid temperature. Finally, the shell-side low-temperature fluid after heat exchange flows out of the heat exchanger from the shell-side outlet pipe 102, and the tube-side high-temperature fluid after heat exchange flows out of the heat exchanger from the tube-side outlet pipe 204.

[0028] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the protection scope of the present invention in any form, and all technical solutions obtained by equivalent replacement and the like fall within the protection scope of the present invention. The parts not involved in the present invention are the same as the prior art or can be implemented by the prior art.

Claims

1. A spiral corrugated tube wall jet shell and tube heat exchanger, comprising a shell (1), a shell side inlet pipe (101), a shell side outlet pipe (102) and a head (2), characterized in that: A shell-side inlet pipe (101) is arranged at the upper right end of the shell (1), and a shell-side outlet pipe (102) is arranged at the lower left end; a head (2) and a tube sheet (3) are arranged on both sides of the shell (1); and a plurality of arched baffles (4) and spiral bellows (5) are arranged inside the shell (1); A left-side head baffle (201) is arranged inside the head (2) on the left side of the shell (1), and the left-side head baffle (201) cooperates with the left-side tube sheet to separate the inside of the left-side head (2) into three or more converging chambers, and at the same time, a tube-side inlet pipe (203) is arranged at the upper end of the left-side head (2) and a tube-side outlet pipe (204) is arranged at the lower end, wherein the tube-side inlet pipe (203) is communicated with the uppermost converging chamber, and the tube-side outlet pipe (204) is communicated with the lowermost converging chamber; A right-side head baffle (202) is arranged inside the head (2) on the right side of the shell (1), and the right-side head baffle (202) cooperates with the right-side tube sheet to separate the inside of the right-side head (2) into two or more converging chambers; The tube sheet (3) is provided with a plurality of tube sheet side wall tube holes (301), and the tube sheet side wall tube holes (301) are connected to and communicate with the ends of the spiral corrugated tube (5); The arcuate baffle (4) is provided with a plurality of arcuate baffle side wall tube holes (401), and the spiral corrugated tube (5) passes through the arcuate baffle side wall tube holes (401).

2. The spiral corrugated tube wall jet shell and tube heat exchanger according to claim 1, characterized in that: The shell-side inlet pipe (101), the shell-side outlet pipe (102) and the arcuate baffle (4) are welded to the shell (1), and the tube-side inlet pipe (203) and the tube-side outlet pipe (204) are welded to the head (2).

3. The spiral corrugated tube wall-mounted jet shell and tube heat exchanger according to claim 1, characterized in that: The left-side head baffle (201), the right-side head baffle (202) and the head (2) are integrally cast and connected to the tube sheet (3) to form a fluid confluence chamber.

4. A spiral corrugated tube wall-mounted jet shell and tube heat exchanger according to claim 1 or 3, characterized in that: Two left-side head baffles (201) are provided, and the two left-side head baffles (201) separate the interior of the left-side head (2) into three fluid converging chambers; One right-side head baffle plate (202) is provided, and one right-side head baffle plate (202) separates the interior of the right-side head (2) into two fluid converging chambers.

5. The spiral corrugated tube wall-mounted jet shell and tube heat exchanger according to claim 4, characterized in that: The three fluid converging chambers separated in the left end cap are respectively the left upper converging chamber, the left middle converging chamber and the left lower converging chamber, and the two fluid converging chambers separated in the right end cap are respectively the right upper converging chamber and the right lower converging chamber, wherein the left upper converging chamber is connected to the pipe inlet pipe (203), the left lower converging chamber is connected to the pipe outlet pipe (204), the right upper converging chamber is connected to the left upper converging chamber and the left middle converging chamber respectively through a spiral bellows (5), and the right lower converging chamber is connected to the left middle converging chamber and the left lower converging chamber respectively through a spiral bellows (5).

6. The spiral corrugated tube wall-mounted jet shell and tube heat exchanger according to claim 1, characterized in that: The wall thickness and diameter of the sealing head (2) are the same as those of the shell (1).

7. The spiral corrugated tube wall jet shell and tube heat exchanger according to claim 1, characterized in that: A plurality of arcuate baffles (4) are arranged in an alternating manner up and down, and form an S-shaped channel with the shell (1).

8. The spiral corrugated tube wall-mounted jet shell and tube heat exchanger according to claim 1, characterized in that: Straight pipe sections (501) having the same diameter as the tube sheet side wall and a length equal to the tube sheet wall thickness are reserved at both ends of the spiral corrugated tube (5). The spiral corrugated tube (5) is connected to the tube sheet (3) and the side wall of the arched baffle (4) by expansion joint.

9. The spiral corrugated tube wall-mounted jet shell and tube heat exchanger according to claim 1, characterized in that: The spiral bellows is an eight-head spiral bellows.

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