A falling film evaporator

Abstract

This utility model provides a falling film evaporator, relating to the field of heat exchanger technology. The falling film evaporator comprises a cylindrical body, heat exchange tubes, two tube sheets, and two elastic seals. The two tube sheets are spaced apart within the cylindrical body along its length. The heat exchange tubes are spaced apart inside the tube sheets. The two elastic seals are located between the heat exchange tubes and the two tube sheets, and are respectively interference-fitted with the heat exchange tubes. This falling film evaporator, by providing elastic seals between the tube sheets and the heat exchange tubes, utilizes its elasticity to abut against the heat exchange tubes and tube sheets, and adapts to possible deformations of the tube sheets and heat exchange tubes, ensuring stable and reliable sealing of the falling film heat exchanger.

Description

Technical Field

[0001] This utility model relates to the field of heat exchanger technology, and in particular to a falling film evaporator. Background Technology

[0002] Falling film evaporator technology utilizes a flow equalization device to generate a uniform flow, effectively utilizing the heat exchange area of ​​the heat exchange tubes in the heat exchange process.

[0003] In existing falling film evaporators, the heat exchange tubes are sealed to the shell using an expansion seal to fix the heat exchange tubes to the shell. However, the expansion seal relies on the elasticity of the heat exchange tubes and the shell itself. The shell or heat exchange tubes will deform due to thermal expansion and contraction, resulting in limited sealing performance.

[0004] In view of this, a new technical solution is needed to solve the above-mentioned technical problems. Utility Model Content

[0005] To address the problem of limited sealing performance of expansion tube seals, the purpose of this invention is to provide a falling film evaporator with good sealing performance.

[0006] To achieve the above objectives, the present invention employs the following technical means:

[0007] This utility model provides a falling film evaporator, comprising:

[0008] cylindrical body;

[0009] Two tube sheets are spaced apart inside the cylinder along the length of the cylinder;

[0010] Heat exchange tubes are spaced apart on the inner side of the tube sheet;

[0011] Two elastic seals are disposed between the heat exchange tube and the two tube sheets, and are respectively interference-fitted with the heat exchange tube.

[0012] Optionally, the tube sheet has a countersunk hole at one end facing the heat exchange tube, and the elastic seal is assembled in the countersunk hole.

[0013] Optionally, the elastic seal has an assembly groove at one end facing the heat exchange tube, and the heat exchange tube is interference-fitted into the assembly groove.

[0014] Optionally, the resilient seal includes a rubber plug.

[0015] Optionally, the heat exchange tube is a single tube, and multiple heat exchange teeth are arranged on the peripheral wall of the single heat exchange tube.

[0016] Optionally, it also includes a liquid distributor, which is disposed between the cylinder and the heat exchange tube. The liquid distributor is bent and its two ends are spaced apart to form a gap, which is located below the heat exchange tube.

[0017] Optionally, the liquid distributor includes a sleeve and an air equalization plate spaced apart from each other, the air equalization plate being disposed inside the sleeve, and two stop portions being provided at both ends of the sleeve and at both ends of the air equalization plate.

[0018] Optionally, the gas distribution plate is provided with a plurality of gas distribution holes evenly arranged thereon.

[0019] Optionally, a refrigerant injection port is provided on one side of the cylinder, and a liquid outlet is provided on the other side, with a baffle plate covering the liquid outlet.

[0020] Optionally, the liquid distributor is spaced apart from the cylinder to form two air outlet channels, and two filters are respectively provided in the two air outlet channels; the cylinder also includes two air outlets, which are respectively opened at the output ends of the two air outlet channels.

[0021] Compared with the prior art, this utility model brings the following technical effects:

[0022] The falling film evaporator of this invention features an elastic sealing element between the tube sheet and the heat exchange tubes. The elastic sealing element uses its own elasticity to abut against the heat exchange tubes and the tube sheet, and adapts to the possible deformation of the tube sheet and the heat exchange tubes, making the sealing of the falling film heat exchanger stable and reliable. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A cross-sectional view of a falling film evaporator according to some embodiments of the present invention is shown;

[0025] Figure 2 It shows Figure 1 A sectional view of section AA;

[0026] Figure 3 An exploded structural diagram of the tube sheet and rubber stopper of some embodiments of the present invention is shown;

[0027] Figure 4 The following are schematic diagrams illustrating the structure of the liquid distributor according to some embodiments of the present invention;

[0028] Figure 5 It shows Figure 4 A sectional view of section BB;

[0029] Figure 6 A schematic diagram of the structure of a heat exchange tube according to some embodiments of the present invention is shown.

[0030] Explanation of key component symbols:

[0031] 10-Cylinder; 11-Tube sheet; 111-Counterhead; 12-Rubber stopper; 121-Assembly groove; 13-Refrigerant filling port; 14-Baffle plate; 15-Liquid outlet; 16-Filter screen; 17-Gas outlet;

[0032] 20 - Heat exchange tube; 21 - Heat exchange tooth; 22 - Inlet end; 23 - Outlet end;

[0033] 30-Liquid distributor; 31-Gas equalization plate; 311-Gas equalization hole; 32-Sleeve; 33-Stop part; 34-Notch. Detailed Implementation

[0034] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0035] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0036] Please see Figures 1-3 This utility model provides a falling film evaporator, including a cylinder 10, heat exchange tubes 20, two tube sheets 11 and two elastic sealing elements. The two tube sheets 11 are spaced apart inside the cylinder 10 along the length direction of the cylinder 10; the heat exchange tubes 20 are spaced apart inside the tube sheets 11; the two elastic sealing elements are disposed between the heat exchange tubes 20 and the two tube sheets 11 and are interference-fitted with the heat exchange tubes 20.

[0037] The falling film evaporator of this invention provides an elastic sealing element between the tube sheet 11 and the heat exchange tube 20. The elastic sealing element uses its own elasticity to abut against the heat exchange tube 20 and the tube sheet 11, and adapts to the possible deformation of the tube sheet 11 and the heat exchange tube 20, so that the sealing of the falling film heat exchanger is stable and reliable.

[0038] The falling film evaporator is a horizontal falling film heat exchanger. That is, the length of the shell 10 in the horizontal direction is much greater than its length in the vertical direction, and the heat exchange tubes 20 inside the shell 10 are arranged in the horizontal direction. The horizontal falling film heat exchanger has a small footprint and no dead zones in heat exchange.

[0039] A cavity is formed inside the cylinder 10 to accommodate the heat exchange tube 20 and the coating device (shown below). Water flows through the inner cavity of the heat exchange tube 20, entering from the inlet 22 of the heat exchange tube 20, exchanging heat with the refrigerant outside the heat exchange tube 20, and finally leaving from the outlet 23 of the heat exchange tube 20.

[0040] In addition, the outer side of the tube sheet 11 is assembled with a water-side sealing gasket (not shown) to prevent water from flowing between the tube side and the shell side.

[0041] Please see Figure 3 In one specific embodiment, a countersunk hole 111 is provided at one end of the tube sheet 11 facing the heat exchange tube 20, and an elastic seal is assembled in the countersunk hole 111.

[0042] The countersunk hole 111 is a through hole with a step. The diameter of the countersunk hole 111 is smaller than the diameter of the elastic seal so that the elastic seal can deform and be inserted into the countersunk hole 111, so that the tube sheet 11 and the elastic seal are interference fit.

[0043] When the heat exchange tube 20 is inserted into the elastic seal, the peripheral wall of the countersunk hole 111 provides radial support to the elastic seal along the heat exchange tube 20, allowing the elastic seal to elastically abut against the heat exchange tube 20. Furthermore, the bottom wall of the countersunk hole 111 provides axial support to the elastic seal along the heat exchange tube 20, ensuring axial abutment of the elastic seal against the heat exchange tube 20, thus guaranteeing stable and reliable axial fixation of the heat exchange tube 20. The tube sheet 11 improves the assembly accuracy of the elastic seal by positioning it axially and radially.

[0044] In addition, the use of elastic seals makes the assembly of heat exchange tubes 20 more standardized and universal, reducing the manufacturing cost of the entire falling film evaporator.

[0045] The resilient seal is detachably connected to the tube sheet 11. Specifically, the resilient seal has a flange on its peripheral wall. The user can pull or remove the resilient seal from the countersunk hole 111 of the tube sheet 11 by holding the flange, thus achieving a detachable connection between the resilient seal and the tube sheet 11. In this way, when the resilient seal is damaged or its elasticity is significantly reduced, the sealing performance of the falling film evaporator can be maintained by replacing it with a new one, resulting in low maintenance costs.

[0046] In one specific embodiment, an assembly groove 121 is provided at one end of the elastic seal facing the heat exchange tube 20, and the heat exchange tube 20 is interference-fitted into the assembly groove 121.

[0047] The heat exchange tube 20 is inserted into the assembly groove 121 of the elastic seal. The assembly groove 121 is cylindrical, and its diameter is configured to be slightly smaller than that of the heat exchange tube 20 so that the heat exchange tube 20 and the elastic seal are connected by an interference fit. In this embodiment, the assembly groove 121 is a stepped hole. The bottom and walls of the assembly groove 121 provide axial and radial elastic support force to the heat exchange tube 20, so that the elastic seal abuts against the heat exchange tube 20. The axial and radial positioning of the heat exchange tube 20 by the elastic seal through the assembly groove 121 further improves the assembly accuracy of the heat exchange tube.

[0048] In one specific embodiment, the resilient seal includes a rubber plug 12.

[0049] The rubber stopper 12 is inherently elastic and can be interference-fitted with both the tube sheet 11 and the heat exchange tubes 20. Furthermore, the tube sheet 11, welded to the shell 10, or the falling film evaporator, will generate a high-temperature environment during prolonged operation. The rubber stopper 12 has strong heat resistance and hardly melts or deforms even at the high temperatures of welding, exhibiting high stability. In addition, the rubber stopper has stable chemical properties and a long service life.

[0050] Please see Figure 1 and Figure 6 In one specific embodiment, the heat exchange tube 20 is a single tube, and a plurality of heat exchange teeth 21 are arranged on the peripheral wall of the heat exchange tube 20.

[0051] In small falling film evaporators, the requirements for heat exchange efficiency are relatively low. Therefore, this embodiment uses a single heat exchange tube 20, resulting in a simple and compact structure for the falling film evaporator. The diameter of this heat exchange tube 20 is larger than that of existing tube bundles to improve the heat exchange efficiency of a single heat exchange tube 20. For example, in this embodiment, the diameter of the heat exchange tube 20 is r1, while the diameter of a conventional heat exchange tube 20 is r2, where r2:r1 = (2~5):1.

[0052] The arrangement of heat exchange teeth 21 increases the contact area between the heat exchange tube 20 and the external refrigerant, further improving the heat exchange efficiency of a single heat exchange tube 20. In this embodiment, the heat exchange teeth 21 are distributed throughout the peripheral wall of the heat exchange tube 20, and the number, shape, and distribution of the heat exchange teeth 21 can be adjusted according to actual needs.

[0053] Please see Figure 4 and Figure 5 In one specific embodiment, the falling film evaporator further includes a liquid distributor 30, which is disposed between the cylinder 10 and the heat exchange tube 20 and surrounds the heat exchange tube 20. The liquid distributor 30 is curved, and its two ends are spaced apart to form a notch 34, which is located below the heat exchange tube 20.

[0054] The distributor 30 evenly sprays the refrigerant onto the heat exchange tube 20, forming a uniform liquid film on the tube. This ensures uniform heat exchange across the entire heat exchange tube 20 and prevents localized overheating. The notch 34 guides the flow of the gaseous and liquid refrigerant after heat exchange. A downward-facing notch guides the refrigerant downwards.

[0055] The liquid distributor 30 is arc-shaped, and the curvature of the liquid distributor 30 is approximately the same as the curvature of the peripheral wall of the heat exchange tube 20. After passing through the liquid distributor 30, the refrigerant can fall directly onto the peripheral wall of the heat exchange tube 20 without flowing excessively on the heat exchange tube 20, thus forming a uniform liquid film on the heat exchange tube 20, resulting in more efficient heat exchange between the refrigerant and the heat exchange tube 20.

[0056] In one specific embodiment, the liquid distributor 30 includes a sleeve 32 and an air equalization plate 31 arranged at intervals. The air equalization plate 31 is located inside the sleeve 32, and two stop portions 33 are respectively provided at both ends of the sleeve 32 and both ends of the air equalization plate 31.

[0057] A liquid storage space is formed between the sleeve 32 and the gas distribution plate 31. Some refrigerant does not pass through the gas distribution plate 31 and is stored in the liquid storage space. The stop part 33 can restrict the direction of the refrigerant located in the liquid storage space so that the refrigerant must pass through the gas distribution plate 31 and exchange heat with the heat exchange tube 20.

[0058] In one specific embodiment, a plurality of air distribution holes 311 are evenly arranged on the air distribution plate 31.

[0059] The multiple air distribution holes 311 have the same diameter and are evenly distributed so that the refrigerant passing through the air distribution plate 31 forms a uniform liquid film on the heat exchange tube 20, thereby improving the uniformity of liquid distribution of the liquid distributor 30.

[0060] Please refer to it again. Figure 1 and Figure 2 In one specific embodiment, a refrigerant injection port 13 is provided on one side of the cylinder 10, and a liquid outlet 15 is provided on the other side, with a baffle plate 14 covering the liquid outlet 15.

[0061] The liquid outlet 15 is located at the bottom of the cylinder 10. The refrigerant first enters the distributor 30 through the refrigerant filling port 13, and then flows out through the gas equalization plate 31 at a certain flow rate, where it exchanges heat evenly with the heat exchange tube 20. After heat exchange, part of the refrigerant remains liquid, while the other part evaporates to form gas. The liquid and gaseous refrigerant flow out through the notch 34 at the bottom of the distributor 30.

[0062] Liquid refrigerant, carrying gaseous refrigerant, moves downwards under the influence of gravity. The baffle plate 14 enables gas-liquid separation of the refrigerant dripping onto it, preventing liquid refrigerant carrying gaseous refrigerant from being discharged from the outlet 15.

[0063] After the liquid refrigerant is discharged from the cylinder 10, the subsequent gaseous refrigerant does not need to pass through the liquid refrigerant deposited in the cylinder 10, and the situation of gaseous refrigerant absorbing liquid is significantly improved.

[0064] Furthermore, the baffle 14 includes a baffle body and two flow sections. The two flow sections are bent downwards and disposed on both sides of the baffle body, and through holes are provided on the flow sections. The baffle body is located on the path of the refrigerant's descent, that is, at the notch 34. Figure 5 Below the stop part 33. The flow section bends downward to guide the liquid refrigerant, after contact with the stop part 33, to flow out of the through hole into the flow section.

[0065] In one specific embodiment, the liquid distributor 30 is spaced apart from the cylinder 10 to form two air outlet channels, and two filters 16 are respectively provided in the two air outlet channels; the cylinder 10 also includes two air outlets 17, which are respectively opened at the output end 23 of the two air outlet channels.

[0066] The gaseous refrigerant enters the outlet channel formed between the distributor 30 and the cylinder 10, and after being filtered by the filter screen 16 to separate the mixed liquid refrigerant, it finally leaves the cylinder 10 through the outlet 17.

[0067] In summary, the working principle of this utility model is as follows: Liquid refrigerant enters the cylinder 10 through the refrigerant inlet 13 and passes through the gas equalization plate of the distributor 30 at a certain flow rate. The outflowing refrigerant forms a uniform liquid film covering the heat exchange tube 20. The liquid film exchanges heat evenly with the heat exchange tube 20, and the refrigerant is converted into liquid or gas and flows out from the lower notch 34 of the distributor 30. The liquid refrigerant drips onto the bottom baffle plate 14 of the distributor 30 under the action of gravity, and is stored at the bottom of the cylinder 10 by the guidance of the baffle plate 14, and then flows out through the liquid outlet 15. The gaseous refrigerant enters the two gas outlet channels formed by the distributor 30 and the cylinder 10, enters the top of the falling film evaporator through the filter screen 16, and then flows out through the two gas outlets 17.

[0068] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom still fall within the protection scope of this invention.

Claims

1. A falling film evaporator, characterized in that include: cylindrical body; Two tube sheets are spaced apart inside the cylinder along the length of the cylinder; Heat exchange tubes are spaced apart on the inner side of the tube sheet; Two elastic seals are disposed between the heat exchange tube and the two tube sheets, and are interference-fitted with the heat exchange tube.

2. The falling film evaporator according to claim 1, characterized in that The tube sheet has a countersunk hole at one end facing the heat exchange tube, and the elastic seal is assembled in the countersunk hole.

3. The falling film evaporator according to claim 2, characterized in that The elastic seal has an assembly groove at one end facing the heat exchange tube, and the heat exchange tube is interference-fitted into the assembly groove.

4. The falling film evaporator of claim 1, wherein The resilient seal includes a rubber stopper.

5. The falling film evaporator according to any one of claims 1 to 4, characterized in that The heat exchange tube is a single tube, and multiple heat exchange teeth are arranged on the peripheral wall of the single heat exchange tube.

6. The falling film evaporator according to any one of claims 1 to 4, characterized in that It also includes a liquid distributor, which is located between the cylinder and the heat exchange tube. The liquid distributor is bent and its two ends are spaced apart to form a gap. The gap is located below the heat exchange tube.

7. The falling film evaporator according to claim 6, characterized in that, The liquid distributor includes a sleeve and an air equalization plate arranged at intervals. The air equalization plate is located inside the sleeve, and two stop portions are provided at both ends of the sleeve and at both ends of the air equalization plate.

8. The falling-film evaporator according to claim 7, characterized in that The gas equalization plate has multiple gas equalization holes evenly arranged on it.

9. The falling film evaporator of claim 6, wherein, The cylinder has a refrigerant injection port on one side and a liquid outlet on the other side, with a baffle plate covering the liquid outlet.

10. The falling film evaporator of claim 7, wherein, The liquid distributor is spaced apart from the cylinder to form two air outlet channels, and two filters are respectively provided in the two air outlet channels; the cylinder also includes two air outlets, which are respectively opened at the output ends of the two air outlet channels.

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