Gas-liquid separator

Abstract

The embodiment of the invention provides a gas-liquid separator, and relates to the field of gas-liquid separation. The gas-liquid separator comprises an outer cylinder body, an inner cylinder body and a heat exchange pipe, the inner cylinder body is arranged in the outer cylinder body and used for being communicated with a first refrigerant medium, an interval cavity is formed by the inner cylinder body and the outer cylinder body, and the heat exchange pipe is arranged in the interval cavity and used for being communicated with a second refrigerant medium; after the first refrigerant medium enters the inner barrel, the first refrigerant medium transfers heat to the inner barrel, the inner barrel transfers the heat to the interval cavity to enable the temperature of the interval cavity to rise, a second refrigerant medium flows in the heat exchange pipe, and the temperature of the second refrigerant medium is lower than that of the interval cavity. And the heat exchange pipe and the second refrigerant medium form a temperature difference with the high-temperature interval cavity, so that the heat exchange pipe and the second refrigerant medium flowing in the heat exchange pipe complete heat exchange with the high-temperature interval cavity, the first refrigerant medium in the inner barrel is directly or indirectly cooled, the refrigeration effect is improved, and the risk of liquid impact of the compressor is reduced.

Description

Technical Field

[0001] The invention relates to the field of gas-liquid separation, and in particular to a gas-liquid separator. Background Art

[0002] In the automotive heat pump system, a gas-liquid separator is installed after the evaporator and before the compressor, which can separate the gas and liquid refrigerants, temporarily store excess refrigerant liquid, protect the compressor, and avoid liquid hammer in the compressor.

[0003] When the temperature of the refrigerant entering the expansion valve is too high, the refrigeration effect will be reduced. However, the commonly used gas-liquid separators do not have the function of cooling the high-temperature refrigerant, which increases the risk of liquid hammer in the compressor. Summary of the invention

[0004] The present invention provides a gas-liquid separator, which can reduce the temperature of a high-temperature refrigerant medium entering the gas-liquid separator.

[0005] The embodiments of the present invention can be implemented as follows:

[0006] An embodiment of the present invention provides a gas-liquid separator, comprising:

[0007] outer cylinder;

[0008] An inner cylinder, which is arranged inside the outer cylinder, and the inner cylinder and the outer cylinder form a partition chamber, and the inner cylinder is used to connect the first refrigerant medium;

[0009] The heat exchange tube is arranged in the partition chamber and is used to connect the second refrigerant medium.

[0010] Optionally, the gas-liquid separator further comprises an upper cover, which is connected to the outer cylinder;

[0011] The upper cover is provided with a first flow channel and a second flow channel, the first flow channel is communicated with the interior of the inner cylinder, and the second flow channel is communicated with the heat exchange tube.

[0012] Optionally, the gas-liquid separator further comprises a lower cover, which is connected to the outer cylinder;

[0013] The lower cover is provided with a third flow channel and a fourth flow channel, the third flow channel is communicated with the partition chamber, and the fourth flow channel is communicated with the heat exchange tube.

[0014] Optionally, the inner cylinder comprises a cylinder body, the upper end of the cylinder body is open, and the upper end opening of the cylinder body is covered with an inner cylinder cover plate;

[0015] The inner cylinder cover plate is connected with a connecting pipe, and the connecting pipe connects the first flow channel with the interior of the inner cylinder.

[0016] Optionally, the gas-liquid separator further comprises a gas-liquid separation component, which is disposed inside the inner cylinder and is used for separating gas phase and liquid phase in the first refrigerant entering the inner cylinder.

[0017] Optionally, the gas-liquid separation component includes a separation plate, and the separation plate is used to separate the gas phase and the liquid phase of the first refrigerant entering the inner cylinder.

[0018] Optionally, the gas-liquid separation component further comprises a separation tube, one end of which is in communication with the interior of the inner cylinder, and the other end of which is in communication with the partition chamber.

[0019] Optionally, the separation tube is arranged inside the inner cylinder, and the separation tube comprises an outer tube body and an inner tube body;

[0020] The outer tube body has a first end and a second end, both of which are open, the first end is connected to the interior of the inner tube body, and the second end is connected to both the inner tube body and the interior of the inner tube body;

[0021] One side of the inner tube body is connected to the inner side wall of the outer tube body, one end of the inner tube body is connected to the second end of the outer tube body, and the other end of the inner tube body is connected to the partition chamber.

[0022] Optionally, the diameter of the lower end of the inner cylinder is contracted.

[0023] Optionally, the outer wall of the heat exchange tube is in close contact with the inner cylinder.

[0024] Optionally, the heat exchange tubes are distributed in the compartment chambers in a spiral shape.

[0025] Optionally, the cross-section of the heat exchange tube is circular, semicircular, rectangular or elliptical.

[0026] The beneficial effects of the gas-liquid separator of the embodiment of the present invention include, for example:

[0027] The gas-liquid separator includes an outer cylinder, an inner cylinder and a heat exchange tube. The inner cylinder is arranged inside the outer cylinder. The inner cylinder is used to connect the first refrigerant, and the inner cylinder and the outer cylinder form a partition chamber. The heat exchange tube is arranged in the partition chamber and is used to connect the second refrigerant. When the first refrigerant enters the inner cylinder, the first refrigerant transfers heat to the inner cylinder, and the inner cylinder transfers heat to the partition chamber to increase the temperature of the partition chamber. The second refrigerant flows in the heat exchange tube, and the temperature of the second refrigerant is lower than the temperature of the partition chamber. The heat exchange tube and the second refrigerant form a temperature difference with the high-temperature partition chamber, so that the heat exchange tube and the second refrigerant flowing inside thereof complete heat exchange with the high-temperature partition chamber, directly or indirectly cool the first refrigerant in the inner cylinder, improve the refrigeration effect, and reduce the risk of liquid hammer in the compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a schematic diagram of the overall structure of the gas-liquid separator provided in an embodiment of the present invention;

[0030] Figure 2 A front view of a gas-liquid separator provided in an embodiment of the present invention;

[0031] Figure 3 for Figure 2 Schematic diagram of the cross section of AA;

[0032] Figure 4 for Figure 2 Schematic cross-section of the middle BB;

[0033] Figure 5 A top view of an inner cylinder provided in an embodiment of the present invention;

[0034] Figure 6 for Figure 5 Schematic cross-section of the CC;

[0035] Figure 7 It is a schematic structural diagram of an inner cylinder provided in an embodiment of the present invention;

[0036] Figure 8 A schematic diagram of the internal structure of a gas-liquid separator provided in an embodiment of the present invention;

[0037] Fig. 9 A schematic diagram of the structure of an upper cover provided in an embodiment of the present invention;

[0038] Fig.10 A schematic diagram of the structure of a lower cover provided in an embodiment of the present invention;

[0039] Fig.11 It is a schematic diagram of the structure of the heat exchange tube provided in an embodiment of the present invention;

[0040] Fig.12 A schematic diagram of the connection between the separation plate and the separation tube provided in an embodiment of the present invention;

[0041] Fig.13 It is a schematic diagram of the structure of a separation tube provided in an embodiment of the present invention;

[0042] Fig.14It is a schematic structural diagram of a separation tube mounting base provided in an embodiment of the present invention.

[0043] Icons: 1-upper cover; 10-first flow channel; 11-second flow channel; 2-lower cover; 20-third flow channel; 21-fourth flow channel; 3-outer cylinder; 4-inner cylinder; 40-cylinder body; 401-avoidance area; 41-inner cylinder cover; 42-connecting pipe; 5-heat exchange tube; 6-gas-liquid separation assembly; 60-separation plate; 61-separation tube; 611-outer tube body; 612-inner tube body; 62-separation tube mounting seat; 621-limiting block; 622-through hole. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0045] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0047] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, they are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply 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 present invention.

[0048] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0049] The terms "comprises," "comprising," or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0050] Unless otherwise clearly specified and limited, the terms "disposed", "connected" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0052] An embodiment of the present invention provides a gas-liquid separator, which has the function of exchanging heat and cooling the first refrigerant, thereby reducing the temperature of the first refrigerant when it enters the expansion valve, improving the refrigeration effect, and reducing the risk of liquid hammer in the compressor. The gas-liquid separator will be described in detail below.

[0053] Please refer to Figures 1 to 6 The gas-liquid separator includes an outer cylinder 3, an inner cylinder 4 and a heat exchange tube 5. The inner cylinder 4 is arranged inside the outer cylinder 3. The inner cylinder 4 is used to connect the first refrigerant, and the inner cylinder 4 and the outer cylinder 3 form a partition chamber. The heat exchange tube 5 is arranged in the partition chamber and is used to connect the second refrigerant. When the first refrigerant enters the inner cylinder 4, the first refrigerant transfers heat to the inner cylinder 4, and the inner cylinder 4 transfers heat to the partition chamber to increase the temperature of the partition chamber. The second refrigerant flows in the heat exchange tube 5, and the temperature of the second refrigerant is lower than the temperature of the partition chamber. The heat exchange tube 5 and the second refrigerant form a temperature difference with the high-temperature partition chamber, so that the heat exchange tube 5 and the second refrigerant flowing inside the heat exchange tube 5 complete heat exchange with the high-temperature partition chamber, directly or indirectly cool the first refrigerant in the inner cylinder 4, reduce the temperature of the first refrigerant when entering the expansion valve, improve the refrigeration effect, and reduce the risk of liquid hammer in the compressor.

[0054] There is a temperature difference between the first cold medium and the second cold medium, and the temperature of the first cold medium is higher than the temperature of the second cold medium.

[0055] refer to Figure 7 The outer cylinder 3 may be a closed tank body with a hollow interior. In this embodiment, the outer cylinder 3 is a cylindrical tube body with two ends connected. The inner cylinder 4 may be an integrally formed tank body with a cavity. When the inner cylinder 4 is an integrally formed tank body, holes need to be opened on the formed tank body to install pipes for inputting and outputting the first cold medium. In this embodiment, the inner cylinder 4 includes a cylinder body 40 and an inner cylinder cover 41. The upper end of the cylinder body 40 is open, and the inner cylinder cover 41 is sealed at the upper end of the cylinder body 40.

[0056] refer to Figures 8 to 10 In this embodiment, the gas-liquid separator also includes an upper cover 1 and a lower cover 2. The upper cover 1 is connected to the upper end of the outer cylinder 3, and the lower cover 2 is connected to the lower end of the outer cylinder 3. The upper cover 1 is provided with a first flow channel 10 and a second flow channel 11, and the lower cover 2 is provided with a third flow channel 20 and a fourth flow channel 21.

[0057] The first flow channel 10 is connected to the interior of the inner cylinder 4. Specifically, a connecting pipe 42 is connected to the inner cylinder cover plate 41. One end of the connecting pipe 42 is inserted into the first flow channel 10, and the other end of the connecting pipe 42 is inserted into the interior of the inner cylinder 4, so that the first flow channel 10 is connected to the interior of the inner cylinder 4. The second flow channel 11 is connected and communicated with one end of the heat exchange tube 5, and the other end of the heat exchange tube 5 is connected and communicated with the fourth flow channel 21. The third flow channel 20 is connected to the partition chamber.

[0058] The heat exchange tube 5 is connected to the second refrigerant to cool the first refrigerant inside the inner cylinder 4, so the inner space of the heat exchange tube 5 needs to be isolated from the partition chamber.

[0059] refer to Fig.11 Combined with Figure 8 In this embodiment, the heat exchange tube 5 is spirally distributed in the compartment chamber, and the spiral heat exchange tube 5 can have a larger contact area with the first refrigerant, which is beneficial to improve the heat exchange efficiency. In other embodiments, the heat exchange tube 5 can also be arranged in the compartment chamber in a serpentine shape.

[0060] The outer wall of the heat exchange tube 5 can be in close contact with the inner cylinder 4, so as to improve the efficiency of heat exchange. Of course, the heat exchange tube 5 can also be spaced apart from the inner cylinder 4.

[0061] Furthermore, the cross section of the heat exchange tube 5 may be circular, semicircular, rectangular, or elliptical. Of course, the cross section is not limited to the above shapes, and may also be other regular or irregular shapes.

[0062] It should be noted that the diameter and length of the heat exchange tube 5 can be adaptively changed according to actual needs.

[0063] refer to Fig.12 Combined with Figure 6 The gas-liquid separator also includes a gas-liquid separation component 6, which is arranged inside the inner cylinder 4, and is used to separate the gas phase and liquid phase of the first refrigerant entering the inner cylinder 4.

[0064] The gas-liquid separation assembly 6 includes a separation plate 60, which is used to separate the gas phase and liquid phase of the first refrigerant entering the inner cylinder 4. The separation plate 60 is located below the inner cylinder cover plate 41 and is spaced apart from the inner cylinder cover plate 41. The end of the connecting pipe 42 is located above the separation plate 60. When the first refrigerant is discharged from the connecting pipe 42, the first refrigerant first impacts the separation plate 60, and the liquid phase in the first refrigerant adheres to the separation plate 60, thereby separating from the gas phase. The liquid phase on the separation plate 60 will flow into the bottom of the inner cylinder 4 along the edge of the separation plate 60.

[0065] refer to Fig.13 The gas-liquid separation component 6 also includes a separation tube 61 . The separation tube 61 is arranged inside the inner cylinder 4 . The separation tube 61 includes an outer tube body 611 and an inner tube body 612 .

[0066] The outer tube body 611 has a first end and a second end, both of which are open, the first end is connected to the interior of the inner tube body 4, and the second end is connected to the inner tube body 612 and the interior of the inner tube body 4. One side of the inner tube body 612 is connected to the inner side wall of the outer tube body 611, the lower end of the inner tube body 612 is connected to the second end of the outer tube body 611, and the upper end of the inner tube body 612 passes through the separation plate 60 and the inner tube cover plate 41 in sequence and then connects to the partition chamber.

[0067] After the initial separation by the separation plate 60, the first cold medium enters the interior of the inner cylinder 4, and most of the liquid phase adheres to the separation plate 60. The gas phase and a small amount of liquid phase remaining in the gas phase enter the outer tube body 611 from the first end of the outer tube body 611, and then enter the inner tube body 612 from the second end of the outer tube body 611, and finally enter the partition chamber from the upper end of the inner tube body 612. The small amount of liquid phase remaining in the gas phase will adhere to the tube walls of the outer tube body 611 and the inner tube body 612 when flowing through the outer tube body 611 and the inner tube body 612, thereby performing secondary gas-liquid separation, thereby improving the effectiveness of gas-liquid separation; the first cold medium entering the partition chamber contacts with the heat exchange tube 5, so that the second cold medium and the first cold medium can fully exchange heat, thereby improving the heat exchange efficiency of the heat exchange tube 5.

[0068] In this embodiment, the second refrigerant is input from the fourth flow channel 21 and output from the second flow channel 11. The second refrigerant flows upward, and the first refrigerant is discharged from the inner tube body 612 and flows downward, so that the second refrigerant and the first refrigerant flow countercurrently with each other, fully exchanging heat, and further improving the heat exchange efficiency of the heat exchange tube 5.

[0069] Furthermore, a partition plate is provided between the outer wall of the inner tube body 612 and the inner wall of the outer tube body 611, through which the liquid phase remaining in the gas phase can be further adhered, thereby reducing the liquid content in the gas phase, and the liquid phase adhered to the partition plate and the tube walls of the inner tube body 612 and the outer tube body 611 flows into the interior of the inner cylinder 4 through the opening at the second end of the outer tube body 611, and is mixed and stored with the initially separated liquid phase. The number of partition plates can be one or more.

[0070] Of course, in order to quickly collect the secondarily separated liquid phase into the inner cylinder 4, the second end of the outer tube 611 is set in a cone, and the bottom of the cone is opened.

[0071] In this embodiment, a separation tube mounting seat 62 is provided on the inner bottom wall of the inner cylinder 4 , and the separation tube 61 is stably disposed inside the inner cylinder 4 through the separation tube mounting seat 62 .

[0072] refer to Fig.14 The separation tube mounting seat 62 is in the shape of a cylindrical bottle cap as a whole, and a plurality of limit blocks 621 are arranged on the inner wall. The plurality of limit blocks 621 are evenly distributed on the inner wall of the separation tube mounting seat 62. Since the second end of the outer tube body 611 is conical, when the second end of the outer tube body 611 is plugged into the separation tube mounting seat 62, the plurality of limit blocks 621 can clamp and limit the second end of the outer tube body 611, thereby ensuring that the outer tube body 611 is vertically and stably arranged inside the inner cylinder body 4.

[0073] The bottom of the separation tube mounting seat 62 is fixed on the inner bottom wall of the inner cylinder 4, and a plurality of through holes 622 are also provided on the circumferential side wall of the separation tube mounting seat 62, through which the liquid phase collected from the walls of the partition plate, the inner tube body 612, and the outer tube body 611 can flow into the interior of the inner cylinder 4.

[0074] Reference again Figure 7 In this embodiment, the tube diameter of the lower end of the inner cylinder 4 is shrunk, that is, the tube diameter of the end of the inner cylinder 4 away from the inner cylinder cover plate 41 is reduced. This design can collect the separated liquid phase at the bottom of the inner cylinder 4 and make the liquid level of the liquid phase in the inner cylinder 4 higher, which is convenient for recycling the liquid phase. On the other hand, there can be a larger spacing space between the heat exchange tube 5, which is convenient for the installation and connection of the heat exchange tube 5.

[0075] The inner cylinder 4 is also provided with an escape area 401 recessed toward the inside thereof for escaping the heat exchange tube 5 , so that the heat exchange tube 5 and the inner cylinder 4 can be compactly arranged inside the outer cylinder 3 .

[0076] The flow path of the first refrigerant in this embodiment is: first flow channel 10 -> connecting pipe 42 -> interior of inner cylinder 4 -> first end of outer tube 611 -> second end of outer tube 611 -> inner tube 612 -> partition chamber -> third flow channel 20 .

[0077] The flow path of the second refrigerant is: the fourth flow channel 21 -> the heat exchange tube 5 -> the second flow channel 11 .

[0078] The gas-liquid separator of the embodiment of the present invention can not only effectively separate the liquid phase in the first refrigerant through the separation plate 60 and the separation tube 61, but also heat exchange and cool the first refrigerant through the heat exchange tube 5, thereby improving the refrigeration effect and reducing the risk of liquid hammer in the compressor. In addition, the gas-liquid separator also has the advantages of simple structure, convenient assembly, excellent heat exchange performance, strong versatility, and low manufacturing cost.

[0079] In addition, the directional descriptions such as up, down, left, right, inside, and outside mentioned in this embodiment are all descriptions based on the drawings, and other embodiments may include but are not limited to such directional descriptions.

[0080] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A gas-liquid separator, characterized in that: include: Outer cylinder (3); An inner cylinder (4), the inner cylinder (4) being arranged inside the outer cylinder (3), and the inner cylinder (4) and the outer cylinder (3) forming a partition chamber, the inner cylinder (4) being used to connect a first cold medium; A heat exchange tube (5), wherein the heat exchange tube (5) is arranged in the compartment chamber, and the heat exchange tube (5) is used to connect to a second cold medium.

2. The gas-liquid separator according to claim 1, characterized in that: The gas-liquid separator further comprises an upper cover (1), wherein the upper cover (1) is connected to the outer cylinder (3); The upper cover (1) is provided with a first flow channel (10) and a second flow channel (11); the first flow channel (10) is connected to the interior of the inner cylinder (4); and the second flow channel (11) is connected to the heat exchange tube (5).

3. The gas-liquid separator according to claim 1, characterized in that: The gas-liquid separator further comprises a lower cover (2), wherein the lower cover (2) is connected to the outer cylinder (3); The lower cover (2) is provided with a third flow channel (20) and a fourth flow channel (21); the third flow channel (20) is in communication with the partition chamber, and the fourth flow channel (21) is in communication with the heat exchange tube (5).

4. The gas-liquid separator according to claim 2, characterized in that: The inner cylinder (4) comprises a cylinder body (40), the upper end of the cylinder body (40) is open, and the upper end opening of the cylinder body (40) is covered with an inner cylinder cover plate (41); The inner cylinder cover plate (41) is connected to a connecting pipe (42), and the connecting pipe (42) connects the first flow channel (10) with the interior of the inner cylinder body (4).

5. The gas-liquid separator according to claim 1, characterized in that: The gas-liquid separator also includes a gas-liquid separation component (6), which is arranged inside the inner cylinder (4) and is used to separate the gas phase and liquid phase of the first cold medium entering the inner cylinder (4).

6. The gas-liquid separator according to claim 5, characterized in that: The gas-liquid separation component (6) comprises a separation plate (60), and the separation plate (60) is used to separate the gas phase and the liquid phase of the first cold medium entering the inner cylinder (4).

7. The gas-liquid separator according to claim 5, characterized in that: The gas-liquid separation component (6) further comprises a separation tube (61), one end of which is in communication with the interior of the inner cylinder (4), and the other end of which is in communication with the partition chamber.

8. The gas-liquid separator according to claim 7, characterized in that: The separation tube (61) is arranged inside the inner cylinder (4), and the separation tube (61) comprises an outer tube body (611) and an inner tube body (612); The outer tube (611) has a first end and a second end, both of which are open, the first end is in communication with the interior of the inner tube (4), and the second end is in communication with both the inner tube (612) and the interior of the inner tube (4); One side of the inner tube body (612) is connected to the inner wall of the outer tube body (611), one end of the inner tube body (612) is connected to the second end of the outer tube body (611), and the other end of the inner tube body (612) is connected to the partition chamber.

9. The gas-liquid separator according to claim 1, characterized in that: The diameter of the lower end of the inner cylinder (4) is contracted.

10. The gas-liquid separator according to claim 1, characterized in that: The outer wall of the heat exchange tube (5) is in close contact with the inner cylinder (4).

11. The gas-liquid separator according to claim 1, characterized in that: The heat exchange tubes (5) are distributed in the compartment chamber in a spiral shape.

12. The gas-liquid separator according to any one of claims 1 to 11, characterized in that: The cross section of the heat exchange tube (5) is circular, semicircular, rectangular or elliptical.

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