Double-layer coil pipe type multi-stage heat exchanger and heat exchange method thereof

Abstract

The invention belongs to the technical field of heat exchange equipment, and particularly relates to a double-layer coil pipe type multi-stage heat exchanger and a heat exchange method thereof.The double-layer coil pipe type multi-stage heat exchanger comprises multiple heat exchanger bodies which are sequentially connected in series, each heat exchanger body comprises an outer cylinder, an inner cylinder, a first-layer coil pipe and a second-layer coil pipe, and each outer cylinder is arranged on the outer wall of the corresponding inner cylinder in a sleeving mode and provided with a fluid inlet and a fluid outlet; a fluid inlet and a fluid outlet which are communicated are formed in the inner cylinders, the fluid outlet of the upper-stage inner cylinder is communicated with the fluid inlet of the lower-stage inner cylinder, and the first-layer coil pipe and the second-layer coil pipe are both arranged in an annular cavity formed by the outer cylinder and the inner cylinders.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchange equipment, and in particular to a double-layer coil type multi-stage heat exchanger and a heat exchange method thereof. Background Art

[0002] Heat exchanger, also known as heat exchanger, is an energy-saving device that realizes heat transfer between materials between two or more fluids at different temperatures, so that part of the heat of the hot fluid is transferred to the cold fluid, so as to achieve the temperature index specified by the process. The heat exchanger industry involves nearly 30 industries such as HVAC, pressure vessels, reclaimed water treatment equipment, chemical industry, petroleum, etc., and is widely used to form an industrial chain. However, the contact area between the coil and the refrigerant storage tank in the traditional coil heat exchanger is small, which limits the heat transfer between the fluid and the wall of the heat exchanger, resulting in low heat exchange efficiency. Summary of the invention

[0003] The present invention is aimed at the above-mentioned problems and specifically designs a double-layer coil type multi-stage heat exchanger and a heat exchange method thereof, so that the heat exchange space is fully utilized and the heat exchange efficiency of the equipment is improved.

[0004] To achieve the above-mentioned purpose, the present invention provides a double-layer coil-type multi-stage heat exchanger, comprising a plurality of groups of heat exchanger bodies connected in series in sequence, wherein the heat exchanger body comprises an outer tube, an inner tube, a first layer of coils and a second layer of coils, wherein the outer tube is sleeved on the outer wall of the inner tube and is provided with a fluid inlet and a fluid outlet, wherein the inner tube is provided with a connected fluid inlet and fluid outlet, and the fluid outlet of the inner tube of the previous stage is connected to the fluid inlet of the inner tube of the next stage, and the first layer of coils and the second layer of coils are both arranged in an annular cavity formed by the outer tube and the inner tube.

[0005] Furthermore, the outer diameter of the first layer of coils is not greater than the inner diameter of the second layer of coils, the first layer of coils is wound around the outer wall of the inner tube, and the second layer of coils is wound around the outer ring of the first layer of coils.

[0006] Furthermore, the first layer of coils and the second layer of coils each include a plurality of staggered spiral tubes, and the fluid outlet of the spiral tube at the previous level is connected to the fluid inlet of the spiral tube at the next level.

[0007] Furthermore, a turbulent element is installed in the spiral tube.

[0008] Furthermore, the turbulence element is a spoiler ball or a fan, the inner wall of the spiral tube is fixedly connected with a plurality of tube clamping grooves, and the turbulence element is clamped in the tube clamping grooves through a connecting piece.

[0009] Furthermore, the connecting member includes a cover shell with a hollow structure and L-shaped plates symmetrically arranged on both sides of the cover shell, one end of the L-shaped plate is fixedly connected to the cover shell, and the other end is clamped in the pipe clamping groove, the turbulence member is rotatably connected to the cover shell, and the turbulence member is located in the upstream direction of the cover shell.

[0010] Furthermore, the turbulence element is also equipped with cleaning brushes, which are symmetrically arranged on both sides of the turbulence element and contact the inner wall of the spiral tube.

[0011] Furthermore, the outer wall of the outer cylinder is provided with a jacket, and the jacket is provided with an inlet and an outlet which are connected to each other.

[0012] Furthermore, a spiral guide plate is fixedly arranged in the jacket, and the guide plate is fixedly connected to multiple groups of intercepting plates.

[0013] The present invention also includes a heat exchange method of a double-layer coil-type multi-stage heat exchanger, comprising the following steps: 1) The refrigerant is injected through the fluid inlet of the first-stage outer cylinder and inner cylinder, and finally discharged from the fluid outlet of the last-stage outer cylinder and inner cylinder; 2) The heat medium is injected through the fluid inlets of the first-stage multiple spiral tubes. Under the action of gravity potential energy, it continuously swirls around the inner wall of the spiral tube, thereby driving the turbulent element to rotate, and finally discharged from the fluid outlet of the corresponding spiral tube of the last stage; 3) The heat medium is injected through the jacket inlet and, also under the action of gravitational potential energy, continuously rotates around the spiral guide plate, and is blocked by the intercepting plate, extending the rotation cycle, and finally discharged from the jacket outlet of the heat exchanger body of the same level.

[0014] In summary, the present invention has the following advantages and beneficial technical effects: 1. The present invention sets a multi-stage heat exchanger body, extends the pipeline, and the temperature difference generated by the series connection is large. Therefore, during heat convection heat exchange, the heat exchange effect is good, and the series-connected heat exchanger bodies are easy to disassemble, repair, and clean, making full use of waste heat and reducing resource waste; the heat exchange structure is modularly designed, and the assembly and application are convenient and fast. It can be flexibly combined according to actual needs to meet the production needs of different situations and improve the scope of application; the multi-section heat exchanger body effectively improves the production efficiency and the output of heating products, while saving production costs and achieving energy saving and environmental protection.

[0015] 2. The double-layer coil of the present invention adopts a compact spiral structure design, which extends the length of the tube and makes full use of the heat exchange space of the outer tube and the inner tube. With the design of the jacket, it can be used for heating with 3 or more media, which is beneficial to improving the heat exchange efficiency; the two layers of spiral tubes increase the contact area with the refrigerant, and better transfer the heat of the heating medium to enhance the heating effect; the spiral design changes the fluid state in the shell, so that the fluid flows in a strong turbulent state, strengthens heat transfer, and greatly improves the heat transfer coefficient. At the same time, the tightly arranged spiral tubes can effectively eliminate the stress and pipeline vibration caused by thermal expansion and contraction.

[0016] 3. The present invention is provided with turbulence pieces, which can enhance heat transfer. At the same time, the centrifugal force generated by the rotation of the turbulence pieces and the cleaning brushes are used to rub against the inner wall of the spiral tube to effectively clean the scale on the tube wall. It is especially suitable for high-viscosity fluid media and can extend the service life of the heat exchanger. The cover is arranged downstream of the turbulence pieces to limit the turbulence pieces and prevent the turbulence pieces from losing and blocking the spiral pipe, thereby ensuring the circulation of the heat exchange medium. The hollow structure increases the air permeability of the cover and reduces the weight of the cover. Combined with the streamlined hemispherical design, it effectively reduces the resistance of the fluid during passage and improves the circulation efficiency of the fluid.

[0017] 4. The jacket in the present invention is used as auxiliary heating and is selectively applied to improve the selectivity and reliability of the heat exchanger heating. When the external temperature of the heat exchanger body is low, the jacket can be used as an insulation layer to enhance the heat exchange efficiency in the outer tube. The setting of the spiral guide plate increases the friction and turbulence of the fluid in the jacket by reducing the cross-sectional area of ​​the fluid and distorting the streamline, thereby changing the flow path and speed of the fluid, improving the heat transfer effect, and extending the cleaning cycle and service life of the heat exchanger. The setting of the interceptor plate further changes the path of the fluid, extends the rotation time of the fluid, gives full play to the heat exchange of the fluid, and reduces energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is a cross-sectional schematic diagram of the present invention; Figure 2 is a schematic diagram of the installation of the turbulence element in the first embodiment of the present invention; Figure 3 is a three-dimensional schematic diagram of a connecting member in Embodiment 1 of the present invention; Figure 4 It is a schematic diagram of the installation of the intercepting plate in the present invention; Figure 5 is a schematic diagram of the installation of the turbulence element in the second embodiment of the present invention; Figure 6 It is a three-dimensional schematic diagram of the connecting piece in the second embodiment of the present invention.

[0019] The reference numerals in the accompanying drawings are: 1. Heat exchanger body; 2. Outer tube; 3. Inner tube; 4. First layer of coil; 5. Second layer of coil; 6. Turbulence parts; 61. Cleaning brush; 7. Connecting piece; 71. Cover; 72. L-shaped plate; 73. Rotating shaft; 8. Jacket; 81. Guide plate; 82. Shut-off plate. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the implementation of the present invention clearer, the technical solution in the embodiment of the present invention will be described in more detail below in conjunction with the drawings in the embodiment of the present invention. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions; the described embodiments are part of the embodiments of the present invention, not all of the embodiments; the embodiments and directional terms described below with reference to the drawings are exemplary and intended to be used to explain the present invention, and cannot be understood as limitations on the present invention; based on the embodiments in 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. The embodiments of the present invention are described in detail below in conjunction with the drawings: The following is combined with Figure 1-Figure 6 The present invention is described in further detail: Embodiment 1 like Figure 1 As shown, this embodiment discloses a double-layer coil-type multi-stage heat exchanger, including a plurality of sets of heat exchanger bodies 1 connected in series, adjacent heat exchanger bodies 1 are fixedly connected, and the preferred connection method is: welding, flange with polytetrafluoroethylene gasket connection, the heat exchanger body 1 includes an outer tube 2, an inner tube 3, a first layer of coils 4 and a second layer of coils 5, the outer tube 2 is sleeved on the outer wall of the inner tube 3, the first-stage outer tube 2 is provided with a fluid inlet, and the last-stage outer tube 2 is provided with a fluid outlet, wherein the fluid outlet is connected to the fluid inlet of the first-stage outer tube 2, the inner tube 3 is provided with a connected fluid inlet and fluid outlet, and the fluid outlet of the upper-stage inner tube 3 is connected to the lower-stage inner tube 3 in sequence. The fluid inlet of the inner tube 3, the first layer coil 4 and the second layer coil 5 are both arranged in the annular cavity formed by the outer tube 2 and the inner tube 3; the outer diameter of the first layer coil 4 is smaller than the inner diameter of the second layer coil 5, the second layer coil 5 is detachably installed on the inner wall of the outer tube 2 through a pipe clamp, the first layer coil 4 is arranged on the inner circle of the second layer coil 5 through a pipe clamp, and the first layer coil 4 surrounds the outer wall of the inner tube 3, and the outer tube 2 and the inner tube 3 are both the inlet and outlet of the refrigerant medium; the first layer coil 4 and the second layer coil 5 each include a plurality of spiral tubes, the two layers of spiral tubes have opposite rotation directions and are intertwined, and the fluid outlet of the upper spiral tube is connected to the fluid inlet of the corresponding spiral tube of the next level.

[0021] like Figure 2-Figure 3 As shown, a turbulent element 6 is installed in the spiral tube; the turbulent element 6 is a spoiler ball, and a group of relative pipe clamping grooves are welded on the inner wall of each bending section of the spiral tube. The pipe clamping groove structure is preferably: a straight-insertion through groove, and the turbulent element 6 is clamped through the pipe clamping groove by a connector 7; the connector 7 includes a hemispherical cover shell 71 with a hollow structure and an L-shaped plate 72 symmetrically arranged on both sides of the cover shell 71, one end of the L-shaped plate 72 is welded to the hemispherical cover shell 71, and the other end is inserted into the pipe clamping groove adapted thereto, and a group of antipodal points are selected in the concave surface of the hemispherical cover shell 71, and the antipodal points Each is installed with a rotating shaft 73 that can rotate around the hemispherical cover shell 71, and the spoiler ball is provided with a group of mounting holes that are compatible with the rotating shaft 73. The spoiler ball is plugged into the rotating shaft 73 at the mounting hole, and the cover shell 71 is rotated at the same time. The concave direction of the hemispherical cover shell 71 is toward the flow direction of the fluid in the spiral tube, and the turbulence element 6 is located in the upstream direction of the cover shell 71; cleaning brushes 61 are symmetrically arranged on both sides of the turbulence element 6, and the cover shell 71 is provided with an annular avoidance groove that matches the cleaning brush 61, so that the cleaning brush 61 contacts the inner wall of the spiral tube.

[0022] like Figure 1-Figure 4 As shown, a jacket 8 is welded to the outer wall of the outer cylinder 2, and the jacket 8 is provided with a connected inlet and outlet; a spiral guide plate 81 is arranged in the annular cavity formed by the jacket 8 and the outer cylinder 2, and a plurality of groups of evenly arranged intercepting plates 82 are welded to the upper surface of the guide plate 81, and the installation line of the intercepting plate 82 is in a broken line shape, and the intercepting plate 82 is not connected to the outer cylinder 2 and the jacket 8.

[0023] Embodiment 2 like Figure 5-Figure 6 As shown, the difference between this embodiment and the first embodiment is that the turbulence element 6 is a fan, and the cover 71 is provided with a rotating shaft 73 from the inner concave vertex toward the center of the sphere, the inner ring of the fan impeller is inserted into the rotating shaft 73, and the concave surface of the impeller faces the downstream area of ​​the fluid, and a cleaning brush 61 is provided on the back of the impeller. When the heat exchange medium passes through the spiral tube, the fluid continuously rotates around the spiral tube until it descends to the turbulence element 6. At this time, the fan is driven to rotate by the impact force of the fluid, thereby forming turbulence in the tube, and the centrifugal force generated by the rotation of the fan and the cleaning brush 61 effectively inhibit the formation of dirt in the tube; the remaining technical features are the same.

[0024] Embodiment 3 A heat exchange method of a double-layer coil-type multi-stage heat exchanger of the present invention is: Step 1: The refrigerant is injected through the fluid inlet of the first-stage outer tube 2 and the inner tube 3, and after heat exchange with the outer wall of the inner tube 3 and the spiral tube in the annular cavity, it is finally discharged from the fluid outlet of the last-stage outer tube 2 and the inner tube 3; Step 2: The heat medium is injected through the fluid inlet of the first-stage spiral tube, and under the action of gravitational potential energy, it continuously swirls around the inner wall of the spiral tube, and is finally discharged from the fluid outlet of the corresponding spiral tube of the last stage. When the heat medium fluid flows through the bend of the spiral tube, stress is applied to the back of the turbulence element 6, which drives the turbulence element 6 to drive the cleaning brush 61 to rotate synchronously, thereby achieving turbulence and cleaning in the spiral tube; Step 3: The heat medium is injected through the inlet of the jacket 8, and is also affected by the gravitational potential energy, and continuously rotates around the spiral guide plate 81, and is finally discharged from the outlet of the jacket 8 of the heat exchanger body 1 of the same level, and is blocked by the intercepting plate 82, thereby reducing the flow rate of the heat medium fluid, extending the rotation period, and achieving sufficient heat exchange.

[0025] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A double-layer coil-type multi-stage heat exchanger, characterized in that: The invention comprises a plurality of sets of heat exchanger bodies connected in series in sequence, wherein the heat exchanger body comprises an outer tube, an inner tube, a first layer of coils and a second layer of coils; the outer tube is sleeved on the outer wall of the inner tube and is provided with a fluid inlet and a fluid outlet; the inner tube is provided with a fluid inlet and a fluid outlet that are connected to each other, and the fluid outlet of the inner tube of the previous stage is connected to the fluid inlet of the inner tube of the next stage; the first layer of coils and the second layer of coils are both arranged in an annular cavity formed by the outer tube and the inner tube.

2. A double-layer coil-type multi-stage heat exchanger according to claim 1, characterized in that: The outer diameter of the first layer of coils is not greater than the inner diameter of the second layer of coils. The first layer of coils is wound around the outer wall of the inner tube, and the second layer of coils is wound around the outer ring of the first layer of coils.

3. A double-layer coil-type multi-stage heat exchanger according to claim 2, characterized in that: The first layer of coils and the second layer of coils both include a plurality of staggered spiral tubes, and the fluid outlet of the upper layer of spiral tubes is connected to the fluid inlet of the lower layer of spiral tubes.

4. A double-layer coil-type multi-stage heat exchanger according to claim 3, characterized in that: A turbulent element is installed in the spiral tube.

5. A double-layer coil-type multi-stage heat exchanger according to claim 4, characterized in that: The turbulence piece is a spoiler ball or a fan, the inner wall of the spiral tube is fixedly connected with a plurality of tube clamping grooves, and the turbulence piece is clamped with the tube clamping grooves through a connecting piece.

6. A double-layer coil-type multi-stage heat exchanger according to claim 5, characterized in that: The connecting member includes a cover shell with a hollow structure and L-shaped plates symmetrically arranged on both sides of the cover shell, one end of the L-shaped plate is fixedly connected to the cover shell, and the other end is clamped in the pipe clamping groove, the turbulence member is rotatably connected to the cover shell through a rotating shaft, and the turbulence member is located in the upstream direction of the cover shell.

7. A double-layer coil-type multi-stage heat exchanger according to claim 6, characterized in that: The turbulent element is further provided with cleaning brushes, which are symmetrically arranged on both sides of the turbulent element and contact the inner wall of the spiral tube.

8. The double-layer coil-type multi-stage heat exchanger according to claim 7, characterized in that: The outer wall of the outer cylinder is provided with a jacket, and the jacket is provided with an inlet and an outlet which are connected to each other.

9. The double-layer coil-type multi-stage heat exchanger according to claim 8, characterized in that: A spiral guide plate is fixedly arranged in the jacket, and the guide plate is fixedly connected to multiple groups of intercepting plates.

10. A heat exchange method of a double-layer coil-type multi-stage heat exchanger, characterized in that: The heat exchange steps of the double-layer coil-type multi-stage heat exchanger described in claim 9 are: Step 1: The refrigerant is injected through the fluid inlet of the first-stage outer cylinder and the inner cylinder, and finally discharged from the fluid outlet of the last-stage outer cylinder and the inner cylinder; Step 2: The heat medium is injected through the fluid inlets of the first-stage multiple spiral tubes respectively, and under the action of gravitational potential energy, it continuously swirls around the inner wall of the spiral tube, thereby driving the turbulent element to rotate, and finally discharged from the fluid outlet of the corresponding spiral tube of the last stage; Step 3: The heat medium is injected through the jacket inlet, and is also affected by the gravitational potential energy, continuously rotating around the spiral guide plate, and is blocked by the intercepting plate, and is finally discharged from the jacket outlet of the heat exchanger body of the same stage.

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