Turbulent flow assembly and heat exchange tube

Abstract

The invention relates to the technical field of shell-and-tube heat exchangers, in particular to a turbulent flow assembly and a heat exchange tube. The invention provides a turbulent flow assembly which comprises first turbulent flow pieces and second turbulent flow pieces, the first turbulent flow pieces and the second turbulent flow pieces extend spirally, the central axes of the first turbulent flow pieces and the central axes of the second turbulent flow pieces are overlapped, and the first turbulent flow pieces and the second turbulent flow pieces are arranged in a staggered mode to form a double-spiral structure. Drainage surfaces are arranged in the extension directions of the first spoiler and the second spoiler and are used for guiding the flow direction of working medium liquid; the first turbulent flow piece and the second turbulent flow piece are provided with flow channels in the axial direction, the flow channels communicate with the drainage face, and the flow channels penetrate through the axial direction of the first turbulent flow piece and the axial direction of the second turbulent flow piece. More vortex structures can be generated to disturb the temperature boundary layer, so that the thickness of the thermal boundary layer is reduced on the whole, and the heat exchange performance is improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of shell and tube heat exchangers, and in particular to a spoiler assembly and a heat exchange tube. Background Art

[0002] In the chemical production process, high viscosity fluids often cause heat exchange tubes to become clogged, while low-speed laminar flow near the wall is prone to fouling. These problems will increase flow resistance, reduce effective heat exchange area, or cause other adverse conditions. In order to solve these problems, manufacturers usually need to regularly clean and repair heat exchangers, which affects the normal operation of the production process.

[0003] There is an urgent need for a flow disturbance component that can break the flow stability of the working fluid, reduce the thickness of the flow boundary layer and slow down the scaling rate to solve the above problems. Summary of the invention

[0004] The present disclosure aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] To this end, a first aspect of the present disclosure provides a spoiler assembly, comprising a first spoiler and a second spoiler, wherein the first spoiler and the second spoiler extend in a spiral and overlap in the central axial direction, and the first spoiler and the second spoiler are arranged alternately to form a double helical structure, and the first spoiler and the second spoiler have a guide surface in the extension direction, and the guide surface is used to guide the flow direction of the working fluid;

[0006] The first spoiler and the second spoiler have flow channels in the axial direction, the flow channels are communicated with the flow guide surface and the flow channels penetrate the first spoiler and the second spoiler in the axial direction.

[0007] In a feasible implementation manner, the first spoiler and the second spoiler are provided with spoiler sections, wherein:

[0008] The spoiler segment on the first spoiler has a spiral direction opposite to that of the first spoiler;

[0009] The spoiler segment on the second spoiler has a spiral direction opposite to that of the second spoiler.

[0010] In a feasible implementation manner, the spoiler section is provided with at least two sections, and the spoiler section is provided in the middle part between the first spoiler and the second spoiler.

[0011] In a feasible implementation manner, the spoiler segment on the first spoiler and the spoiler segment on the second spoiler are arranged in opposite positions.

[0012] In a feasible implementation manner, the spiral twist ratio of the first spoiler and the second spoiler is set to 1:1 to 5:1.

[0013] In a feasible implementation manner, the thickness of the first spoiler and the second spoiler is set to 0.5 to 3.0 mm.

[0014] In a feasible implementation manner, the width of the drainage surface is set to 3 to 7 mm, and the diameter of the flow channel is set to 7 to 11 mm.

[0015] In a second aspect of the present disclosure, a heat exchange tube is provided, comprising a tube body and a spoiler assembly as described in any one of claims 1 to 9, wherein a liquid inlet is provided at one end of the tube body and a liquid outlet is provided at the other opposite end; the spoiler assembly is arranged in the tube body, and the extension direction of the spoiler assembly is consistent with that of the tube body.

[0016] In a feasible implementation manner, the inner wall or the outer wall of the tube body is provided with a porous layer.

[0017] In a feasible implementation manner, the porosity range of the porous layer is set to be 20% to 80%.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects: the first spoiler and the second spoiler of the present invention form a double helix structure, which can guide the flow direction of the working fluid, and improve the heat exchange performance by guiding the working fluid to form turbulence in the tube. The present invention can generate more vortex structures, disturb the temperature boundary layer, thereby reducing the thickness of the thermal boundary layer as a whole and improving the heat exchange performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0021] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the exemplary embodiments below. The accompanying drawings are only for the purpose of illustrating exemplary embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0022] Figure 1It is a schematic structural diagram of the first spoiler and the second spoiler provided in the heat exchange tube of the present invention without the spoiler section;

[0023] Figure 2 It is a schematic structural diagram of a first spoiler and a second spoiler provided in a heat exchange tube and provided with a spoiler section according to the present invention;

[0024] Figure 3 A schematic diagram of the structure of the first spoiler and the second spoiler of the present invention provided with spoiler sections;

[0025] Figure 4 It is a schematic structural diagram of the first spoiler and the second spoiler of the present invention without spoiler sections.

[0026] in, Figures 1 to 4 The corresponding relationship between the reference numerals and the component names is: 1-first spoiler; 2-second spoiler; 3-guiding surface; 4-flow channel; 5-spoiler section; 6-tube body; 7-liquid inlet; 8-liquid outlet. DETAILED DESCRIPTION

[0027] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0029] In the heat exchange process of a shell and tube heat exchanger, the hot and cold fluids transfer heat through the tube wall. Typically, shell and tube heat exchangers use smooth tubes for heat exchange, and the materials include ordinary carbon steel or corrosion-resistant steel tubes. However, these types of heat exchange tubes are limited by the structure and generally have low heat transfer efficiency, resulting in a large heat exchanger design area and high equipment investment. In order to improve the heat exchange effect, the thermal boundary layer of the working fluid should be destroyed, and the turbulent kinetic energy of the working fluid should be increased, thereby improving the heat exchange effect.

[0030] Based on this, an embodiment of the present disclosure provides a spoiler assembly, wherein a first spoiler and a second spoiler form a double helix structure, which can guide the flow direction of the working fluid liquid, guide the working fluid liquid to form turbulence in the tube, disturb the temperature boundary layer, thereby reducing the thickness of the thermal boundary layer as a whole, improving the heat exchange performance, and improving the heat exchange performance.

[0031] The spoiler component is described in detail below through a specific embodiment:

[0032] Reference Figures 1 to 4As shown, in a first aspect of the present disclosure, a spoiler assembly is provided, comprising a first spoiler 1 and a second spoiler 2, the first spoiler 1 and the second spoiler 2 extending spirally and overlapping in the central axial direction, and the first spoiler 1 and the second spoiler 2 are staggered to form a double helix structure, the first spoiler 1 and the second spoiler 2 have a guide surface 3 in the extension direction, and the guide surface 3 is used to guide the flow direction of the working fluid; the first spoiler 1 and the second spoiler 2 have a flow channel 4 in the axial direction, the flow channel 4 is connected to the guide surface 3 and the flow channel 4 runs through the axial direction of the first spoiler 1 and the second spoiler 2.

[0033] The present invention can be arranged in a heat exchange tube by a fixed connection or a detachable connection such as a clamping connection or a welding connection, and the present invention specifically adopts a welding method to achieve the effect of reducing costs and facilitating installation. The first spoiler 1 and the second spoiler 2 of the present invention form a double helix structure, specifically, the first spoiler 1 and the second spoiler 2 can be selected from rolled right-handed blades and left-handed blades, the first spoiler 1 and the second spoiler 2 of the present invention The spiral twisted parts do not touch, and the middle part where the first spoiler 1 and the second spoiler 2 are combined is set as a hollow flow channel 4, when the working fluid flows in from one end, part of it flows along the guide surface 3 of the first spoiler 1 and the second spoiler 2, and part of it flows to the other side along the flow channel 4, in this process, the working fluid in the flow channel 4 will merge with the working fluid on the guide surface 3, and in this process, the radial heat exchange effect of the fluid can be further improved. By arranging the present invention in the heat exchange tube, the flow trajectory of the fluid in the heat exchange tube can be changed, so that the original straight line type becomes a spiral type, the flow rate of the fluid in the tube is increased, and the heat transfer coefficient is improved. It should be noted that when the torsion of the first spoiler 1 and the second spoiler 2 is relatively small, the flow velocity is higher, thereby improving the heat transfer coefficient, but also bringing greater flow resistance. The two ends of the molded right-handed blade and left-handed blade are spot-welded to the heat exchange tube. Compared with spoilers in a single direction, spoilers with alternating rotation directions can periodically change the direction of fluid flow, provide higher wall flow velocity, and significantly enhance the heat transfer effect.

[0034] In some embodiments, in order to better destroy the boundary layer of the working fluid to form turbulence, a spoiler section 5 is provided on the first spoiler 1 and the second spoiler 2. Specifically, the spoiler section 5 is integrally formed with the first spoiler 1 and the second spoiler 2 where it is located and has opposite spiral directions.

[0035] In some embodiments, the spoiler section 5 is provided with at least one section, and the spoiler section 5 is provided behind the first spoiler 1 and the second spoiler 2. It should be understood that the spoiler section 5 is provided at intervals, that is, the normal parts of the first spoiler 1 and the second spoiler 2 are set as A, and the spoiler section 5 is set as B, and its structure is ABABA from one end to the other end. However, it can be understood that in this embodiment, the working fluid is intended to flow in a non-single spiral direction, and its setting order can be adjusted.

[0036] In some embodiments, the helical twist ratio of the first spoiler 1 and the second spoiler 2 is set to 1:1 to 5:1, where the helical twist ratio is the ratio of the length of the helical sheet rotated 360° to the outer diameter.

[0037] In some embodiments, the thickness of the first spoiler 1 and the second spoiler 2 is set to 0.5 to 3.0 mm. Specifically, in the present disclosure, the thickness of the first spoiler 1 and the second spoiler 2 is specifically set to 2 mm.

[0038] In some embodiments, the width of the guide surface 3 is set to 3 to 7 mm, and the diameter of the flow channel 4 is set to 7 to 11 mm. Specifically, when a heat exchange tube with a specification of φ-25×2×2000 mm is used, the present disclosure can select a blade thickness of 2 mm, a flow channel diameter of 9 mm, and a blade (guide surface) width of 5 mm.

[0039] In a second aspect of the present disclosure, a heat exchange tube is provided, characterized in that it includes a tube body 6 and a spoiler assembly according to any one of claims 1 to 9, wherein a liquid inlet 7 is provided at one end of the tube body 6 and a liquid outlet 8 is provided at the other opposite end; the spoiler assembly is arranged in the tube body 6, and the extension direction of the spoiler assembly is consistent with that of the tube body 6.

[0040] In some embodiments, the inner wall or the outer wall of the tube body 6 of the present disclosure is provided with a porous layer.

[0041] In the present disclosure, the boiling heat transfer rate of the heat exchange tube provided with a porous layer is closely related to the speed at which bubbles are generated on the heat transfer surface. The vaporization cores on the surface of the smooth heat exchange tube are generated at the surface defects. There are countless artificial vaporization cores on the surface of the heat exchange tube provided with a porous layer, which greatly accelerates the bubble nucleation rate. As the bubbles grow and escape, the interconnected porous layers accelerate the stirring of the local liquid due to the siphon effect, generating overall convective heat transfer. The boiling heat transfer of the heat exchange tube provided with a porous layer is mainly carried out in three ways: convective heat transfer between the liquid film and the wall surface in the tunnel, thin film evaporation, and overall convection. The porous layer increases the microscopic heat transfer area, and the porous layer is a metal material with high thermal conductivity. In some embodiments, the porosity range of the porous layer is set to 20% to 80%.

[0042] The following is a comparative test of the embodiment of the technical solution disclosed in the present invention and the heat exchange tube without spoilers:

[0043] Embodiment 1:

[0044] The heated fluid flows from bottom to top in the tube. The first spoiler 1 and the second spoiler 2 with spoiler sections 5 are arranged in the tube to guide the fluid to form multiple swirls and periodically change the flow direction of the fluid in the tube, thereby increasing the turbulence of the flow, generating more vortex structures, and disturbing the temperature boundary layer.

[0045] In this embodiment, the heat exchange tube has a specification of φ25×2×200mm; the material is stainless steel; the spiral bond torsion ratio is 2:1; the spoiler section 5 is set as one section; the thickness of the combined internal part is 2mm, the inner diameter is 9mm, and the outer diameter is 19mm.

[0046] The experimental medium is water, with an inlet velocity of 0.5 m / s, an inlet temperature of 20°C, an inlet pressure of 100 kPaA, and a tube wall temperature of 100°C. After the outlet temperature stabilizes, the average outlet temperature is measured to be 43.3°C, and the tube side heat transfer coefficient is 1647.6 W / K·m 2 .

[0047] Embodiment 2:

[0048] According to the conditions and steps described in Example 1, a one-way spoiler element is placed in the tube.

[0049] In this embodiment, the heat exchange tube has a specification of φ25×2×200mm; the material is stainless steel; the spiral bond torsion ratio is 2:1; the spoiler section 5 is not provided in this embodiment, and the thickness of the combined internal part is 2mm, the inner diameter is 9mm, and the outer diameter is 19mm.

[0050] The experimental medium is water, with an inlet velocity of 0.5 m / s, an inlet temperature of 20°C, an inlet pressure of 100 kPaA, and a tube wall temperature of 100°C. After the outlet temperature stabilizes, the average outlet temperature is measured to be 37.2°C, and the tube side heat transfer coefficient is 1418.7 W / K·m 2 .

[0051] Comparative Example:

[0052] According to the conditions and steps described in Example 1, no spoiler element is placed.

[0053] The heat exchange tube is a bare tube, that is, the spoiler assembly disclosed in the present invention is not provided, with a specification of φ25×2×200mm; and the material is stainless steel.

[0054] The experimental medium is water, with an inlet flow rate of 0.5m / s, an inlet temperature of 20℃, an inlet pressure of 100kPaA, and a tube wall temperature of 100℃. After the outlet temperature stabilizes, the average outlet temperature is measured to be 25.6℃, and the heat flux of the tube wall is 1095.5W / K·m 2 .

[0055] From the calculation results of the embodiment and the comparative example, it can be seen that the heat exchange effect of the embodiment 1 and the embodiment 2 is better than that of the heat exchange tube of the comparative example without the spoiler assembly of the present disclosure, and the heat exchange effect of the embodiment 1 provided with the spoiler section 5 is better than that of the embodiment 2. Taking the comparative example as a reference, the improvement effect of the heat transfer coefficient of the embodiment 1 and the embodiment 2 is 50.4% and 29.5% respectively. Therefore, adding a spoiler element in the heat exchange tube can significantly improve the heat exchange effect.

[0056] In the present disclosure, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise expressly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to the specific circumstances.

[0057] In the description of the present disclosure, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "left", "right", "front", "back", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, should not be understood as a limitation on the present disclosure.

[0058] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means 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 present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0059] The above are only preferred embodiments of the present disclosure and are not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A spoiler component, characterized in that: It comprises a first spoiler and a second spoiler, wherein the first spoiler and the second spoiler extend in a spiral and their central axes overlap each other, and the first spoiler and the second spoiler are arranged alternately to form a double helix structure, wherein: The first spoiler and the second spoiler have guide surfaces in their extending directions, and the guide surfaces are used to guide the flow direction of the working fluid; The first spoiler and the second spoiler have flow channels in the axial direction, the flow channels are communicated with the flow guide surface and the flow channels penetrate the first spoiler and the second spoiler in the axial direction.

2. The spoiler assembly according to claim 1, characterized in that: The first spoiler and the second spoiler are provided with spoiler sections, wherein: The spoiler segment on the first spoiler has a spiral direction opposite to that of the first spoiler; The spoiler segment on the second spoiler has a spiral direction opposite to that of the second spoiler.

3. The spoiler assembly according to claim 2, characterized in that: The spoiler section is provided with at least two sections, and the spoiler section is provided in the middle part of the first spoiler and the second spoiler.

4. The spoiler assembly according to claim 2, characterized in that: The spoiler section on the first spoiler and the spoiler section on the second spoiler are arranged in opposite positions.

5. The spoiler assembly according to claim 1, characterized in that: The spiral twist ratio of the first spoiler and the second spoiler is set to 1:1 to 5:

1.

6. The spoiler assembly according to claim 1, characterized in that: The thickness of the first spoiler and the second spoiler is set to 0.5 to 3.0 mm.

7. The spoiler assembly according to claim 1, characterized in that: The width of the drainage surface is set to 3 to 7 mm, and the diameter of the flow channel is set to 7 to 11 mm.

8. A heat exchange tube, characterized in that: The invention comprises a tube body and a spoiler assembly as claimed in any one of claims 1 to 9, wherein: The tube body is provided with a liquid inlet at one end and a liquid outlet at the other opposite end; The spoiler component is arranged in the tube body, and the extension direction of the spoiler component is consistent with that of the tube body.

9. The spoiler assembly according to claim 8, characterized in that: The inner wall or the outer wall of the tube body is provided with a porous layer.

10. The spoiler assembly according to claim 9, characterized in that: The porosity of the porous layer is set in a range of 20% to 80%.

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