Single-tube heat exchanger

Abstract

The utility model provides a single-tube heat exchanger which comprises an outer shell and an inner tube, the outer shell and the inner tube extend in the first direction, the inner tube is arranged in an inner cavity of the outer shell, one end of the outer shell is provided with a cold fluid inlet, the other end of the outer shell is provided with a cold fluid outlet, and one end of the inner tube is provided with a hot fluid outlet. A hot fluid inlet is formed in the other end of the inner pipe, the inner pipe comprises a finned pipe section and a porous pipe section, and the finned pipe section and the porous pipe section are sequentially arranged in the direction from the hot fluid inlet to the hot fluid outlet. According to the single-tube heat exchanger, the inner tube is used for flowing of the hot fluid, the space between the shell and the inner tube is used for flowing of the cold fluid, and the inner tube comprises the finned tube section and the porous tube section so as to be matched with forms and heat exchange characteristics of different stages in the heat exchange process of the cold fluid, so that the heat exchange efficiency is high in different stages; therefore, the single-tube heat exchanger has high heat exchange efficiency, and the size of the single-tube heat exchanger can be smaller under the same heat exchange load.

Description

TECHNICAL FIELD

[0001] The utility model relates to heat exchange equipment field, concretely relates to a single tube heat exchanger. BACKGROUND

[0002] The heat exchanger is the equipment that passes part heat of hot fluid to cold fluid, also called heat exchanger. Single tube heat exchanger, especially single tube heat exchanger with organic working medium, the heat exchange process mainly includes: liquid convection heat exchange in preheating stage, evaporation heat exchange in phase change stage, gaseous convection heat exchange in superheating stage. In the related art, the tube type of single tube heat exchanger is invariable, leading to low heat exchange efficiency of single tube heat exchanger. SUMMARY

[0003] The utility model aims at at least in certain extent solves one of the technical problems in the related art. For this purpose, the embodiment of the utility model proposes a single tube heat exchanger, and the single tube heat exchanger has higher heat exchange efficiency.

[0004] The single tube heat exchanger of the utility model embodiment comprises:

[0005] The shell extends along the first direction, and one end of the shell along the first direction is provided with a cold fluid inlet, and the other end of the shell along the first direction is provided with a cold fluid outlet;

[0006] The inner tube extends along the first direction and is arranged in the inner cavity of the shell, one end of the inner tube along the first direction is provided with a hot fluid outlet, the other end of the inner tube along the first direction is provided with a hot fluid inlet, and the inner tube comprises a finned tube segment and a porous tube segment, and the finned tube segment and the porous tube segment are sequentially arranged along the direction from the hot fluid inlet to the hot fluid outlet.

[0007] The single tube heat exchanger of the utility model embodiment is provided with the shell and the inner tube, the inner tube is used for hot fluid flow, the shell and the inner tube are used for cold fluid flow, the inner tube comprises the finned tube segment and the porous tube segment, so as to match the form and heat exchange characteristics of different stages in the heat exchange process of cold fluid, so as to have higher heat exchange efficiency in different stages, so that the single tube heat exchanger has higher heat exchange efficiency, and the single tube heat exchanger can realize smaller volume under the same heat exchange load.

[0008] In some embodiments, the porous tube segment comprises a first tube segment body and a first fin, the first tube segment body extends along the first direction, the first fin comprises a radial portion and an axial portion, the radial portion is arranged on the outer circumferential surface of the first tube segment body and extends along the radial direction of the first tube segment body, and the axial portion is arranged on one end of the radial portion away from the first tube segment body and extends along the axial direction of the first tube segment body.

[0009] In some embodiments, the finned tube section comprises a second tube section body extending along the first direction and a second fin provided on an outer circumferential surface of the second tube section body and extending along a radial direction of the second tube section body.

[0010] In some embodiments, the porous tube section comprises a high-fin-density section and a low-fin-density section arranged in sequence along the first direction, the low-fin-density section being located between the high-fin-density section and the finned tube section.

[0011] In some embodiments, the number of the first fins of the high-fin-density section is 55FPI-60FPI, and the number of the first fins of the low-fin-density section is 40FPI-50FPI.

[0012] In some embodiments, the fin height of the first fin is 0.4mm-0.8mm.

[0013] In some embodiments, the fin height of the second fin is 14mm-18mm, and the spacing between two adjacent second fins is 4mm-6mm.

[0014] In some embodiments, an inner circumferential surface of the inner tube is provided with a turbulence element extending along the first direction, or a plurality of turbulence elements are arranged at intervals along the first direction.

[0015] In some embodiments, the turbulence element is an internal thread provided on the inner circumferential surface of the inner tube, the internal thread extending along the first direction.

[0016] In some embodiments, the shell has a flange portion at each end along the first direction. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a structural schematic view of a single-tube heat exchanger according to an embodiment of the present application;

[0018] Figure 2 is a partial cross-sectional view of a finned tube section according to an embodiment of the present application;

[0019] Figure 3 is Figure 2 an enlarged schematic view of part A in FIG. 4.

[0020] REFERENCE NUMERALS:

[0021] 1. Outer shell; 11. Cold fluid inlet; 12. Cold fluid outlet; 13. Flange; 2. Inner tube; 21. Hot fluid outlet; 22. Hot fluid inlet; 23. Finned tube section; 231. Second tube section body; 232. Second fin; 24. Porous tube section; 241. First tube section body; 242. First fin; 2421. Radial section; 2422. Axial section; 243. High fin ratio section; 244. Low fin ratio section; 25. Turbulence element. Detailed Implementation

[0022] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0023] The following is for reference. Figures 1-3 A single-tube heat exchanger according to an embodiment of the present invention is described.

[0024] like Figures 1-3 As shown, the single-tube heat exchanger of this utility model embodiment includes an outer shell 1 and an inner tube 2.

[0025] The outer casing 1 along the first direction (e.g.) Figure 1 Extending in the left-right direction (as shown), the outer shell 1 has a cold fluid inlet 11 at one end along the first direction and a cold fluid outlet 12 at the other end along the first direction. The inner tube 2 extends along the first direction and is disposed in the inner cavity of the outer shell 1. The inner tube 2 has a hot fluid outlet 21 at one end along the first direction and a hot fluid inlet 22 at the other end along the first direction. The inner tube 2 includes a finned tube section 23 and a porous tube section 24, which are arranged sequentially from the hot fluid inlet 22 to the hot fluid outlet 21.

[0026] like Figure 1 As shown, both the outer shell 1 and the inner tube 2 extend in the left-right direction, with the inner tube 2 located within the inner cavity of the outer shell 1. A cold fluid inlet 11 is located at the left end of the outer shell 1, which can be located on the left end face or the outer peripheral surface of the left end of the outer shell 1, preferably on the left end face. A cold fluid outlet 12 is located at the right end of the outer shell 1, which can be located on the right end face or the outer peripheral surface of the right end of the outer shell 1, preferably on the right end face. Cold fluid enters the outer shell 1 through the cold fluid inlet 11 and flows from left to right within the space between the outer shell 1 and the inner tube 2, then exits from the cold fluid outlet 12.

[0027] The left end surface of the inner tube 2 is provided with a hot fluid outlet 21, and the right end surface of the inner tube 2 is provided with a hot fluid inlet 22. The hot fluid enters the inner cavity of the inner tube 2 through the hot fluid inlet 22 and flows from right to left, and then is discharged from the hot fluid inlet 22. The cold fluid and the hot fluid exchange heat in the process of flowing in opposite directions.

[0028] The inner tube 2 comprises a finned tube section 23 and a porous tube section 24, which are arranged in sequence along the direction from right to left.

[0029] In the process of heat exchange between the cold fluid and the hot fluid, according to the form and heat exchange characteristics of the fluid, it is divided into a liquid phase zone, a gas-liquid zone and a gas phase zone from left to right. The finned tube section 23 is arranged in the gas phase zone, and the porous tube section 24 is arranged in the gas-liquid zone and the liquid phase zone. The liquid cold fluid enters the shell 1 first, and then sequentially exchanges heat with the hot fluid in the porous tube section 24 in a liquid state and evaporates, and is heated into a saturated liquid. Then, the saturated liquid exchanges heat with the hot fluid in the finned tube section 23 in a gaseous state, and finally generates superheated gas, which is discharged from the cold fluid outlet 12. The finned tube section 23 and the porous tube section 24 of the inner tube 2 can match the form and heat exchange characteristics of the cold fluid at different stages of the heat exchange process, so as to increase the vaporization core or the heat exchange area, thereby strengthening the heat exchange, improving the heat exchange efficiency, and realizing a smaller volume and reducing the amount of cold fluid under the condition of a certain heat exchange amount.

[0030] The single-tube heat exchanger of the embodiment of the utility model is provided with a sleeved shell and an inner tube. The inner tube is used for hot fluid flow, and the shell and the inner tube are used for cold fluid flow. The inner tube comprises a finned tube section and a porous tube section, so as to match the form and heat exchange characteristics of the cold fluid at different stages of the heat exchange process, so as to have a higher heat exchange efficiency at different stages, thereby making the single-tube heat exchanger have a higher heat exchange efficiency, and making the single-tube heat exchanger realize a smaller volume under the same heat exchange load.

[0031] In some embodiments, the porous tube section 24 comprises a first tube section body 241 and a first fin 242. The first tube section body 241 extends along a first direction. The first fin 242 comprises a radial portion 2421 and an axial portion 2422. The radial portion 2421 is arranged on the outer peripheral surface of the first tube section body 241 and extends along the radial direction of the first tube section body 241. The axial portion 2422 is arranged on the end of the radial portion 2421 away from the first tube section body 241 and extends along the axial direction of the first tube section body 241.

[0032] As Figures 1-3As shown, the porous pipe section 24 includes a first pipe section body 241 and a first fin 242. The first pipe section body 241 extends in the left-right direction. The first fin 242 is provided on the outer periphery of the first pipe section body 241. The first fin 242 can be a thread shape arranged around the axis of the first pipe section body 241 and extends in the left-right direction. The first fin 242 can also be an annular shape arranged around the axis of the first pipe section body 241. Multiple annular first fins 242 are arranged at intervals in the left-right direction.

[0033] The first fin 242 includes a radial portion 2421 and an axial portion 2422. The radial portion 2421 is disposed on the outer peripheral surface of the first pipe section body 241 and extends radially outward from the outer peripheral surface of the first pipe section body 241. The axial portion 2422 is disposed at the outer end of the radial portion 2421 and extends in the left-right direction. Preferably, the outer end of the radial portion 2421 is connected to the middle of the axial portion 2422. In other words, the cross-section of the first fin 242 is T-shaped. It is understood that in some other embodiments, the cross-section of the first fin 242 may also be L-shaped.

[0034] The first fins 242 can form a dense porous structure, increasing the vaporization nuclei and enhancing the nucleation boiling heat transfer of the cold fluid. At the same time, it can reduce the thermal resistance between the gaseous cold fluid and the wall of the inner tube 2, which is beneficial to heat exchange and thus improves the heat transfer efficiency of the gas-liquid region and the liquid phase region.

[0035] In some embodiments, the porous tube section 24 includes a high fin ratio section 243 and a low fin ratio section 244 arranged sequentially along a first direction, with the low fin ratio section 244 located between the high fin ratio section 243 and the finned tube section 23.

[0036] like Figures 1-3 As shown, the porous tube section 24 includes a high fin ratio section 243 and a low fin ratio section 244 arranged sequentially in the left-right direction. The low fin ratio section 244 connects the high fin ratio section 243 and the finned tube section 23. Both the high fin ratio section 243 and the low fin ratio section 244 include a first tube body 241 and a first fin 242. The density of the first fin 242 in the high fin ratio section 243 is greater than the density of the first fin 242 in the low fin ratio section 244. The high fin ratio section 243 and the low fin ratio section 244 can be an integral structure or two connected tube bodies.

[0037] The high-fin-ratio section 243 is located in the liquid phase region, and the low-fin-ratio section 244 is located in the gas-liquid region. The liquid cold fluid enters the outer shell 1 and first undergoes liquid-phase convective heat exchange with the hot fluid in the high-fin-ratio section 243, being heated to a saturated liquid. Then, it undergoes evaporative heat exchange with the hot fluid in the low-fin-ratio section 244, being heated to a saturated vapor. Finally, it undergoes gas-phase convective heat exchange with the hot fluid in the finned tube section 23, ultimately generating superheated gas. By matching the shape and heat exchange characteristics of the cold fluid in the liquid phase region to the high-fin-ratio section 243, and matching the shape and heat exchange characteristics of the cold fluid in the gas-liquid region to the low-fin-ratio section 244, both the liquid phase and gas-liquid regions achieve high heat exchange efficiency.

[0038] Preferably, the number of first fins 242 in the high wing ratio segment 243 is 55 FPI to 60 FPI, for example, 55 FPI, 57 FPI, 58 FPI, 59 FPI, or 60 FPI. The number of first fins 242 in the low wing ratio segment 244 is 40 FPI to 50 FPI, for example, 40 FPI, 42 FPI, 45 FPI, 48 FPI, or 50 FPI.

[0039] Preferably, the fin height of the first fin 242 is 0.4mm to 0.8mm, for example, 0.4mm, 0.5mm, 0.7mm, or 0.8mm.

[0040] In some embodiments, the finned tube segment 23 includes a second tube segment body 231 and a second fin 232. The second tube segment body 231 extends along a first direction, and the second fin 232 is disposed on the outer peripheral surface of the second tube segment body 231 and extends radially along the second tube segment body 231.

[0041] like Figure 1 As shown, the finned tube segment 23 includes a second tube segment body 231 and a second fin 232. The second tube segment body 231 extends in the left-right direction, and its left end is connected to the right end of the first tube segment body 241 of the low-fin ratio segment 244. The second fin 232 is disposed on the outer peripheral surface of the second tube segment body 231 and extends radially along the second tube segment body 231. Preferably, the second fin 232 is a plate extending radially along the second tube segment body 231; more preferably, the second fin 232 is an annular ring around the axis of the second tube segment body 231. Multiple second fins 232 are arranged at intervals in the left-right direction.

[0042] The second fin 232 can increase the heat exchange area between the gaseous cold fluid and the wall of the inner tube 2, thereby improving the heat exchange efficiency in the gas phase region.

[0043] Preferably, the fin height of the second fin 232 is 14mm to 18mm, for example, 14mm, 15mm, 16mm, or 18mm. The spacing between two adjacent second fins 232 is 4mm to 6mm, for example, 4mm, 5mm, or 6mm.

[0044] In some embodiments, the inner circumferential surface of the inner tube 2 is provided with the turbulence member 25, and the turbulence member 25 extends in the first direction, or a plurality of turbulence members 25 are arranged in the first direction at intervals.

[0045] As shown in Figure 2 and Figure 3 , the inner circumferential surface of the inner tube 2 is provided with the turbulence member 25, and the inner circumferential surface of the first tube segment body 241 and the second tube segment body 231 is provided with the turbulence member 25, and when the heat fluid flows in the inner cavity of the inner tube 2, the heat fluid collides with the turbulence member 25 and generates turbulence, which improves the disturbance of the heat fluid, thereby improving the heat exchange efficiency.

[0046] Preferably, the turbulence member 25 is an internal thread provided on the inner circumferential surface of the inner tube 2, and the internal thread extends in the left-right direction.

[0047] It can be understood that in other embodiments, the turbulence member 25 can also be a turbulence plate provided on the inner circumferential surface of the inner tube 2, the turbulence plate extends in the left-right direction and is arranged obliquely along the radial direction of the inner tube 2, and a plurality of turbulence plates are arranged in the left-right direction at intervals.

[0048] In some embodiments, the outer shell 1 has a flange portion 13 at both ends in the first direction.

[0049] As shown in Figure 1 , the outer circumferential surface of the outer shell 1 is provided with the flange portion 13, and the left and right ends of the outer shell 1 are each provided with a corresponding flange portion 13, so as to facilitate the installation, fixation and disassembly of the single-tube heat exchanger.

[0050] In the description of the present application, it should be understood that the terms "left", "right", "inner", "outer", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0051] In addition, the terms "first" and "second" are only used for distinction, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0052] In the utility model, unless another definite provision and limitation, the terms "mount", "link", "connect", "fix" and so on should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or be integrated;Can be mechanical connection, also can be electric connection or each other can communicate;Can be direct connection, also can indirectly connect through intermediate medium, can be two element internal communication or two element mutual action relation, unless another definite limitation.For ordinary skilled person in the art, can understand the specific meaning of above terms in the utility model according to specific circumstances.

[0053] In the utility model, unless another definite provision and limitation, first feature is "on" or "under" second feature, can be first and second features direct contact, or first and second features indirectly contact through intermediate medium.And, first feature "over", "above" and "on" second feature, can be first feature directly above or obliquely above second feature, or just indicate that the horizontal height of first feature is higher than second feature.First feature "under", "below" and "under" second feature, can be first feature directly below or obliquely below second feature, or just indicate that the horizontal height of first feature is less than second feature.

[0054] In the utility model, the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model.In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.And, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.In addition, the skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of different embodiments or examples without contradiction.

[0055] Although the above embodiments have been shown and described, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the utility model, and the changes, modifications, replacements and variations of the above embodiments made by the ordinary skilled in the art are within the protection scope of the utility model.

Claims

1. A single-tube heat exchanger, characterized in that, include: The outer casing (1) extends along a first direction, and a cold fluid inlet (11) is provided at one end of the outer casing (1) along the first direction, and a cold fluid outlet (12) is provided at the other end of the outer casing (1) along the first direction; An inner tube (2) extends along a first direction and is disposed in the inner cavity of the outer shell (1). One end of the inner tube (2) along the first direction is provided with a hot fluid outlet (21), and the other end of the inner tube (2) along the first direction is provided with a hot fluid inlet (22). The inner tube (2) includes a finned tube section (23) and a porous tube section (24). The finned tube section (23) and the porous tube section (24) are arranged sequentially along the direction from the hot fluid inlet (22) to the hot fluid outlet (21).

2. The single-tube heat exchanger according to claim 1, characterized in that, The porous pipe segment (24) includes a first pipe segment body (241) and a first fin (242). The first pipe segment body (241) extends along the first direction. The first fin (242) includes a radial portion (2421) and an axial portion (2422). The radial portion (2421) is disposed on the outer peripheral surface of the first pipe segment body (241) and extends radially along the first pipe segment body (241). The axial portion (2422) is disposed at one end of the radial portion (2421) away from the first pipe segment body (241) and extends axially along the first pipe segment body (241).

3. The single-tube heat exchanger according to claim 1, characterized in that, The finned tube segment (23) includes a second tube segment body (231) and a second fin (232). The second tube segment body (231) extends along the first direction, and the second fin (232) is disposed on the outer peripheral surface of the second tube segment body (231) and extends radially along the second tube segment body (231).

4. The single-tube heat exchanger according to claim 2, characterized in that, The porous tube section (24) includes a high wing ratio section (243) and a low wing ratio section (244) arranged sequentially along the first direction, wherein the low wing ratio section (244) is located between the high wing ratio section (243) and the finned tube section (23).

5. The single-tube heat exchanger according to claim 4, characterized in that, The number of the first fins (242) in the high fin ratio section (243) is 55 FPI to 60 FPI, and the number of the first fins (242) in the low fin ratio section (244) is 40 FPI to 50 FPI.

6. The single-tube heat exchanger according to claim 2, characterized in that, The fin height of the first fin (242) is 0.4 mm to 0.8 mm.

7. The single-tube heat exchanger according to claim 3, characterized in that, The fin height of the second fin (232) is 14mm to 18mm, and the distance between two adjacent second fins (232) is 4mm to 6mm.

8. The single-tube heat exchanger according to claim 1, characterized in that, The inner circumferential surface of the inner tube (2) is provided with a turbulence element (25), which extends in the first direction, or multiple turbulence elements (25) are arranged at intervals along the first direction.

9. The single-tube heat exchanger according to claim 8, characterized in that, The turbulence element (25) is an internal thread provided on the inner circumferential surface of the inner tube (2), and the internal thread extends along the first direction.

10. The single-tube heat exchanger according to claim 1, characterized in that, The outer casing (1) has flange portions (13) at both ends along the first direction.

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