Distributor of falling film evaporator, falling film evaporator and refrigerating unit

Abstract

The utility model relates to the technical field of air conditioning equipment, in particular to a distributor of a falling film evaporator, the falling film evaporator and a refrigerating unit, the distributor of the falling film evaporator comprises an evaporator top plate arranged at the top of an evaporation chamber of the falling film evaporator, the evaporator top plate is provided with a gravity chamber, and the bottom of the gravity chamber is provided with a plurality of flow distribution holes; each distributor assembly comprises a liquid inlet pipe and a pressure box, the liquid inlet pipe is communicated with the refrigerant pipeline and the pressure box, the pressure box is arranged above the gravity chamber, and first transition holes are uniformly distributed between the pressure box and the gravity chamber; the liquid inlet pipes of the two distributor assemblies are close to the two ends of the evaporator top plate in the length direction respectively. According to the scheme, the defects that in the prior art, refrigerants in a large evaporator are distributed unevenly in the axial direction, and the flow at the two ends is unbalanced in the small-load operation state are overcome, the distribution uniformity of the refrigerants in the range of the evaporator barrel is improved, and the evaporation efficiency and the system stability are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of air-conditioning equipment, in particular to a distributor of a falling film evaporator, a falling film evaporator and a refrigeration unit. Background Art

[0002] In the refrigeration industry, falling film evaporators have attracted wide attention and are widely used due to their high heat transfer performance and their ability to handle high viscosity and easily crystallized solutions. Especially in large-capacity refrigeration units, in order to meet greater heat exchange requirements, the evaporator barrel is designed to be longer. However, as the size of the evaporator increases, uniform distribution of the refrigerant becomes a key technical challenge.

[0003] Although in small or medium-sized evaporators, a relatively uniform refrigerant distribution can be achieved in the axial direction of the cylinder through a well-designed liquid distributor, in large evaporators, even with an optimized distributor, it is difficult to maintain the dynamic flow balance of the refrigerant in the long axial direction, especially when the refrigeration unit is in a low-load operation state, which often manifests as a greater refrigerant flow rate near the liquid inlet than at the far end, resulting in uneven evaporation efficiency in the axial direction, affecting the overall heat exchange performance and stable operation of the system. Uneven refrigerant distribution not only reduces the efficiency of the evaporator, but may also cause local overcooling or overheating, posing a potential threat to the long-term reliability and safety of the refrigeration system. Utility Model Content

[0004] The utility model provides a distributor for a falling film evaporator, a falling film evaporator and a refrigeration unit, which are used to solve the defects of uneven distribution of refrigerant in the axial direction inside large evaporators in the prior art and unbalanced flow at both ends under low-load operation, thereby improving the uniformity of refrigerant distribution within the evaporator cylinder, and enhancing evaporation efficiency and system stability.

[0005] The utility model provides a distributor for a falling film evaporator, comprising: an evaporator top plate, arranged on the top of an evaporation chamber of the falling film evaporator, the evaporator top plate being provided with a gravity chamber, the bottom of the gravity chamber being provided with a plurality of distribution holes; two groups of distributor components, the distributor components comprising a liquid inlet pipe and a pressure box, the liquid inlet pipe being connected to a refrigerant pipeline and the pressure box, the pressure box being arranged above the gravity chamber, and first transition holes being evenly distributed between the pressure box and the gravity chamber; the positions of the liquid inlet pipes of the two groups of the distributor components are respectively close to the two ends of the length direction of the evaporator top plate.

[0006] According to a distributor of a falling film evaporator provided by the utility model, the pressure boxes of two groups of the distributor components have the same length.

[0007] According to a distributor of a falling film evaporator provided by the utility model, the length of the pressure box is less than or equal to the length of the evaporator top plate; the pressure boxes of two groups of the distributor assemblies are distributed in parallel in the width direction of the evaporator top plate.

[0008] According to a distributor of a falling film evaporator provided by the utility model, the cross-sectional area of ​​the pressure box gradually decreases from the connection position of the liquid inlet pipe to the far end of the pressure box.

[0009] According to a distributor of a falling film evaporator provided by the utility model, the horizontal plane projection shape of the pressure box is an isosceles trapezoid.

[0010] According to a distributor of a falling film evaporator provided by the utility model, two groups of distributor components are centrally symmetrical structures to each other.

[0011] According to a distributor of a falling film evaporator provided by the utility model, the evaporator top plate has a convex portion, and two groups of distributor components are arranged above the convex portion; a flanged orifice plate is arranged below the convex portion, and the gravity chamber is formed between the convex portion and the flanged orifice plate, and the distribution hole is a flanged process hole on the flanged orifice plate, and the flanged part of the distribution hole protrudes from the lower surface of the flanged orifice plate.

[0012] According to a distributor of a falling film evaporator provided by the utility model, an intermediate plate is arranged between the flanged orifice plate and the convex portion, and second transition holes are evenly distributed on the intermediate plate; the number of the second transition holes is greater than the number of the distribution holes, and the aperture of the second transition hole is smaller than the aperture of the distribution hole.

[0013] According to a distributor of a falling film evaporator provided by the utility model, a partition extending along the center line of the length direction of the pressure box is arranged in the pressure box; the partition divides the interior of the pressure box into two independent pressure chambers, each of the pressure chambers is connected to the gravity chamber through the first transition hole, and the connection position of the liquid inlet pipe is located on the center line of the length direction of the pressure box.

[0014] The utility model also provides a falling film evaporator, comprising the distributor of the falling film evaporator described in any one of the above embodiments.

[0015] According to a falling film evaporator provided by the utility model, the length of the falling film evaporator is greater than or equal to 4m.

[0016] The utility model also provides a refrigeration unit, comprising the falling film evaporator described in the above embodiment.

[0017] The utility model provides a distributor of a falling film evaporator, a falling film evaporator and a refrigeration unit. A gravity chamber is arranged in the top plate, and the bottom distribution holes use gravity to evenly distribute the refrigerant to the heat exchange tube bundle, thereby improving the heat exchange efficiency and system stability. The distributor assembly adopts a double parallel design, each group contains a liquid inlet pipe and a pressure box. The liquid inlet pipe is connected to the refrigerant circulation system. The refrigerant first enters the pressure box for buffering, and then smoothly enters the gravity chamber through the evenly arranged first transition holes to reduce the concentration gradient and flow resistance. In order to solve the problem of uneven axial refrigerant distribution in large evaporators, especially the imbalance of flow at both ends under small loads, two groups of liquid inlet pipes are respectively arranged at both ends of the length direction of the top plate to ensure that the refrigerant is evenly distributed in the length direction of the evaporator, thereby improving the evaporation efficiency and the overall system performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a structural schematic diagram of a distributor of a falling film evaporator provided by the utility model;

[0020] Figure 2 It is a schematic cross-sectional structural diagram of a distributor of a falling film evaporator provided by the utility model;

[0021] Reference numerals:

[0022] 10. Evaporator top plate; 11. Gravity chamber; 12. Distribution hole; 13. Convex part; 14. Flanged orifice plate; 15. Middle plate; 21. Liquid inlet pipe; 22. Pressure box; 23. Partition plate; 24. Pressure chamber. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be described clearly and completely in conjunction with the drawings in the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] In the description of the embodiments of the present utility model, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present utility model. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. It should also be noted that in the description of the present utility model, unless otherwise clearly specified and limited, the terms "set", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances.

[0025] When the existing falling film evaporator is in operation, the refrigerant enters the pressure box from one end through the liquid inlet pipe and flows to the other end. However, since the initial state of the refrigerant is often a mixture of gas and liquid rather than an ideal uniform distribution, it is impossible to ensure that the amount of refrigerant flowing out of the distributor along the axis of the evaporator is uniform during the actual flow process. Usually, the refrigerant flow rate at the end far away from the liquid inlet pipe is relatively small. In view of this, the utility model aims to solve the problems of uneven axial refrigerant distribution and unbalanced flow rates at both ends of large evaporators during low-load operation, and provides a distributor solution for a falling film evaporator that can improve the uniformity of refrigerant distribution within the evaporator cylinder.

[0026] Combine the following Figure 1-Figure 2 The specific implementation of the distributor of the falling film evaporator of the present invention is described.

[0027] like Figure 1 and Figure 2 As shown, the utility model provides a distributor of a falling film evaporator, comprising: an evaporator top plate 10, arranged at the top of the evaporation chamber of the falling film evaporator, the evaporator top plate 10 is provided with a gravity chamber 11, and a plurality of distribution holes 12 are provided at the bottom of the gravity chamber 11; two groups of distributor components, the distributor components include a liquid inlet pipe 21 and a pressure box 22, the liquid inlet pipe 21 is connected to the refrigerant pipeline and the pressure box 22, the pressure box 22 is arranged above the gravity chamber 11, and first transition holes are evenly distributed between the pressure box 22 and the gravity chamber 11; the positions of the liquid inlet pipes 21 of the two groups of distributor components are respectively close to the two ends of the length direction of the evaporator top plate 10. Based on the distributor of the falling film evaporator proposed by the utility model, the problems of uneven axial distribution of refrigerant and unstable flow rate when load fluctuates faced by large evaporators in practical applications are solved.

[0028] Specifically, an evaporator top plate 10 is provided on the top of the falling film evaporator, and a gravity chamber 11 is embedded inside the evaporator top plate 10. The gravity chamber 11 is arranged with a series of distribution holes 12 at its bottom, and its main function is to use the natural effect of gravity to make the refrigerant more evenly distributed when entering the heat exchange tube bundle or other heat exchange device in the evaporation chamber, thereby improving the heat exchange efficiency and system stability.

[0029] In addition, the distributor assembly of the utility model adopts a double parallel integrated structure, and each group of distributor assemblies includes a liquid inlet pipe 21 and a pressure box 22. The liquid inlet pipe 21 is connected to the refrigerant circulation system of the refrigeration unit, and the refrigerant is accurately introduced into the pressure box 22 for temporary storage and buffering. The pressure box 22 is positioned directly above the gravity chamber 11, and is connected to the gravity chamber 11 through a series of evenly arranged first transition holes to ensure that the refrigerant flows from the pressure box 22 to the gravity chamber 11. The process is smoothly transitioned to achieve preliminary uniform dispersion to reduce local concentration differences and flow resistance.

[0030] Among them, the liquid inlet pipes 21 of the two groups of distributor assemblies are respectively arranged at the positions close to the two ends of the length direction of the evaporator top plate 10, and the two-phase flow refrigerants flowing in from the two ends of the evaporator have their own pressure boxes 22, thereby effectively solving the problem of uneven refrigerant distribution that is easy to occur in large falling film evaporators during actual operation, especially under small load conditions, due to the large axial length of the evaporator, especially the phenomenon of flow imbalance at both ends, thereby improving the uniformity of axial distribution of the refrigerant in the entire evaporator cylinder, and effectively ensuring the evaporation efficiency and the stable and efficient operation of the entire refrigeration system.

[0031] like Figure 1 As shown, according to a distributor of a falling film evaporator provided by the utility model, the lengths of the pressure boxes 22 of the two groups of distributor assemblies are preferably the same, so as to avoid uneven flow caused by the volume difference of the pressure boxes 22. The same length design not only helps to ensure the consistency of the working characteristics of the two groups of distributor assemblies, prevent the change of the dynamic characteristics of the refrigerant due to structural differences, and ensure the operating stability and efficiency of the entire evaporator, but also facilitates standardized production and assembly, reduces production costs, and is also convenient for later maintenance and replacement.

[0032] According to a distributor of a falling film evaporator provided by the utility model, the length of the pressure box 22 is less than or equal to the length of the evaporator top plate 10. It can be understood that the pressure box 22 can be adapted according to the specific structure and requirements of the evaporator to ensure compact and effective space utilization. The pressure boxes 22 of the two groups of distributor assemblies can be coaxially arranged, each acting on half the length of the evaporator top plate 10, or, preferably, the pressure boxes 22 of the two groups of distributor assemblies are distributed in parallel in the width direction of the evaporator top plate 10.

[0033] Specifically, when coaxially arranged, the two groups of pressure boxes 22 each occupy half of the length of the evaporator top plate 10, ensuring uniform axial refrigerant distribution of the long cylindrical evaporator, effectively solving the problem of flow imbalance at both ends during low-load operation due to the large length. In the preferred parallel distribution scheme, the pressure boxes 22 are arranged in parallel along the width direction of the top plate. When the liquid inlet pipe 21 is located at both ends of the top plate length, it is not only conducive to uniform diffusion of refrigerant on the cross section, but also helps to solve the problem of uneven axial distribution, improve evaporation efficiency and system stability, and simplify the structural design, facilitating installation and maintenance.

[0034] The horizontal projection shape of the pressure box 22 can be a rectangle or other geometric shape that matches the evaporator top plate 10. Figure 1 As shown, according to a distributor of a falling film evaporator provided by the utility model, the cross-sectional area of ​​the pressure box 22 gradually decreases from the connection position of the liquid inlet pipe 21 to the far end of the pressure box 22. Through this tapered structural design, the refrigerant can be more evenly distributed after flowing into the pressure box 22.

[0035] When the refrigerant enters the pressure box 22 from the liquid inlet pipe 21, the cross-sectional area gradually decreases, which helps to overcome the problem of local accumulation or rapid flow, and promotes the flow of the refrigerant in various parts of the pressure box 22 to be consistent, and finally achieves a more precise and uniform distribution, thereby improving the uniformity of the refrigerant distribution before entering the gravity chamber 11, which is beneficial to improving the operating efficiency and stability of the entire evaporator.

[0036] According to a distributor of a falling film evaporator provided by the utility model, the shape of the pressure box 22 of the above-mentioned tapered structure can be a triangle, a right-angled trapezoid, etc., and by gradually reducing the cross-sectional area, the refrigerant can produce a relatively uniform flow distribution inside the pressure box 22 after entering it, thereby improving the uniformity of the refrigerant supply to the evaporator. Preferably, the horizontal plane projection shape of the pressure box 22 is an isosceles trapezoid, so that it can better adapt to the spatial layout of the evaporator top plate 10 and form a symmetrical distribution on the refrigerant flow path. The pressure boxes 22 of the two groups of distributor assemblies are preferably arranged in opposite directions, and the tapering directions of the two are opposite, which helps to form a complementary refrigerant distribution trend in the axial direction of the evaporator, and effectively overcomes the problem of uneven axial refrigerant distribution caused by the large length of the evaporator.

[0037] Furthermore, according to the distributor of the falling film evaporator provided by the utility model, the two groups of distributor components are centrally symmetrical structures. The symmetrical design can not only ensure that the two groups of components function in a balanced manner, but also provide convenience in equipment assembly and maintenance, thereby improving the operating efficiency and reliability of the entire refrigeration system.

[0038] like Figure 2As shown, according to a distributor of a falling film evaporator provided by the utility model, the evaporator top plate 10 has a convex portion 13, and two groups of distributor components are arranged above the convex portion 13; a flanged orifice plate 14 is arranged below the convex portion 13, and a gravity chamber 11 is formed between the convex portion 13 and the flanged orifice plate 14, and the distribution hole 12 is a flanged process hole on the flanged orifice plate 14, and the flanged part of the distribution hole 12 protrudes from the lower surface of the flanged orifice plate 14. Among them, the flanged orifice plate 14 and the convex portion 13 together constitute the gravity chamber 11 mentioned above, which is used to assist the refrigerant in the key area of ​​uniform distribution inside the evaporator. The distribution hole 12 mentioned above is actually a hole formed by flanging process on the flanged orifice plate 14, and the structural strength of the orifice plate is enhanced by the flanging process.

[0039] Specifically, the flanged portion of the distribution hole 12 extends beyond the lower surface of the flanged orifice plate 14, which not only enhances the mechanical strength of the flanged orifice plate 14 itself and prevents deformation or damage under pressure and gravity, but also ensures that the flanged portion does not hinder the smooth flow of the refrigerant from top to bottom, thereby effectively ensuring that the refrigerant can flow evenly through the gravity chamber 11 and be further evenly distributed to the heat exchange tube bundle or other heat exchange elements in the evaporator, thereby improving the evaporation efficiency and the operating stability of the entire refrigeration system.

[0040] like Figure 2 As shown, according to a distributor of a falling film evaporator provided by the utility model, an intermediate plate 15 is arranged between the flanged orifice plate 14 and the convex portion 13, and second transition holes are evenly distributed on the intermediate plate 15; the number of the second transition holes is greater than the number of the distribution holes 12, and the aperture of the second transition holes is smaller than the aperture of the distribution holes 12. Compared with the distribution holes 12, the number of the second transition holes is greater and the aperture is smaller, so that the flow control and step-by-step release of the refrigerant during the flow can be refined to promote more uniform distribution of the refrigerant in the evaporator.

[0041] Specifically, the middle plate 15 divides the original gravity chamber 11 into two parts: the upper chamber and the lower chamber. During operation, the refrigerant first enters the upper chamber of the gravity chamber 11 from the pressure box 22 of the distributor assembly through multiple first transition holes, and then passes through multiple second transition holes on the middle plate 15, and is further evenly distributed to the lower chamber. Finally, the refrigerant enters the evaporation chamber through the distribution hole 12 on the flanged orifice plate 14, contacts the heat exchange tube bundle in the evaporation chamber, exchanges heat, and realizes the evaporation process. Through the phased, multi-level distribution and transition design, not only the problem of uneven refrigerant distribution in the axial direction of the large evaporator is effectively alleviated, but also the evaporation efficiency and system stability are improved to a certain extent. At the same time, the design of multi-stage transition holes is also conducive to ensuring that the refrigerant flow at both ends of the evaporator tends to be balanced under different working conditions, especially under low load operation, thereby ensuring the efficient and stable operation of the entire refrigeration system.

[0042] like Figure 2 As shown, according to a distributor of a falling film evaporator provided by the utility model, a partition 23 extending along the center line of the length direction of the pressure box 22 is preferably provided in the pressure box 22; the partition 23 divides the interior of the pressure box 22 into two independent pressure chambers 24, each of which is connected to the gravity chamber 11 through the first transition hole, and the connection position of the liquid inlet pipe 21 is located on the center line of the length direction of the pressure box 22. The partition 23 can divide the internal space of the pressure box 22 into two independent pressure chambers 24, each of which can be connected to the gravity chamber 11 under the evaporator top plate 10 through the first transition hole mentioned above.

[0043] In specific operation, the refrigerant from the refrigerant pipeline is injected into the pressure box 22 through the liquid inlet pipe 21, and the connection position of the liquid inlet pipe 21 is located on the center line of the length direction of the pressure box 22, so that the refrigerant can be evenly distributed to the two independent pressure chambers 24, and then flow down step by step through the corresponding first transition holes into the gravity chamber 11, and finally flow evenly into the evaporation chamber for evaporation. The design of the pressure box 22 with two pressure chambers 24 helps to further optimize the distribution of the refrigerant inside the pressure box 22.

[0044] The utility model also provides a falling film evaporator, including a distributor of the falling film evaporator of any of the above embodiments. By adopting the distributor of the falling film evaporator, the falling film evaporator can achieve a relatively reliable uniformity of refrigerant distribution under large-size design requirements. Further, when the distributor of the falling film evaporator provided by the utility model is adopted, the length of the falling film evaporator can be set to be greater than or equal to 4m to meet a larger cooling capacity requirement.

[0045] Furthermore, the utility model also provides a refrigeration unit, comprising the falling film evaporator of the above embodiment.

[0046] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "mode", "specific mode", or "some modes" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or mode are included in at least one embodiment or mode of the utility model embodiment. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or mode. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or modes in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or modes described in this specification and the features of the different embodiments or modes, without contradiction.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. 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 various embodiments of the utility model.

Claims

1. A distributor for a falling film evaporator, characterized in that: include: An evaporator top plate (10) is arranged on the top of the evaporation chamber of the falling film evaporator, the evaporator top plate (10) is provided with a gravity chamber (11), and a plurality of distribution holes (12) are provided at the bottom of the gravity chamber (11); Two groups of distributor assemblies, the distributor assemblies comprising a liquid inlet pipe (21) and a pressure box (22), the liquid inlet pipe (21) being connected to a refrigerant pipeline and the pressure box (22), the pressure box (22) being arranged above the gravity chamber (11), and first transition holes being evenly distributed between the pressure box (22) and the gravity chamber (11); The positions of the liquid inlet pipes (21) of the two groups of the distributor assemblies are respectively close to the two ends of the evaporator top plate (10) in the length direction.

2. The distributor of the falling film evaporator according to claim 1, characterized in that: The pressure boxes (22) of the two sets of dispenser assemblies have the same length.

3. The distributor of the falling film evaporator according to claim 2, characterized in that: The length of the pressure box (22) is less than or equal to the length of the evaporator top plate (10); The pressure boxes (22) of the two groups of the distributor assemblies are distributed in parallel in the width direction of the evaporator top plate (10).

4. The distributor of the falling film evaporator according to claim 2, characterized in that: From the connection position of the liquid inlet pipe (21) to the distal end of the pressure box (22), the cross-sectional area of ​​the pressure box (22) gradually decreases.

5. The distributor of the falling film evaporator according to claim 4, characterized in that: The horizontal plane projection shape of the pressure box (22) is an isosceles trapezoid.

6. The distributor of the falling film evaporator according to any one of claims 1 to 5, characterized in that: The two groups of distributor components are centrally symmetrical structures to each other.

7. The distributor of the falling film evaporator according to claim 6, characterized in that: The evaporator top plate (10) has a convex portion (13), and the two groups of distributor assemblies are arranged above the convex portion (13); A flanged orifice plate (14) is provided below the convex portion (13), and the gravity chamber (11) is formed between the convex portion (13) and the flanged orifice plate (14). The distribution hole (12) is a flanged process hole on the flanged orifice plate (14), and the flanged portion of the distribution hole (12) protrudes from the lower surface of the flanged orifice plate (14).

8. The distributor of the falling film evaporator according to claim 7, characterized in that: An intermediate plate (15) is provided between the flanged perforated plate (14) and the convex portion (13), and second transition holes are evenly distributed on the intermediate plate (15); The number of the second transition holes is greater than the number of the flow distribution holes (12), and the diameter of the second transition holes is smaller than the diameter of the flow distribution holes (12).

9. The distributor of the falling film evaporator according to claim 6, characterized in that: The pressure box (22) is provided with a partition (23) extending along the center line of the length direction of the pressure box (22); The partition (23) divides the interior of the pressure box (22) into two independent pressure chambers (24), each of the pressure chambers (24) is connected to the gravity chamber (11) through the first transition hole, and the liquid inlet pipe (21) is located on the center line of the length direction of the pressure box (22).

10. A falling film evaporator, characterized in that: A distributor comprising the falling film evaporator according to any one of claims 1 to 9.

11. The falling film evaporator according to claim 10, characterized in that The length of the falling film evaporator is greater than or equal to 4 m.

12. A refrigeration unit, characterized in that: Comprising the falling film evaporator according to claim 10 or 11.

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