Air electric heating device with central shunting and spiral diversion structure

Abstract

The invention relates to an air electric heating device with a central shunting and spiral flow guiding structure. The air electric heating device comprises a heat preservation outer shell, an air pipe, an electric heating pipe and an air outlet. A plurality of air distribution openings are formed in the pipe wall of the air pipe at intervals in the axial direction and used for dispersing air entering the air pipe to the outer side of the air pipe in the radial direction. A plurality of separation pieces are fixedly arranged on the outer wall of the air pipe at intervals in the axial direction, a heating interval is formed between every two adjacent separation pieces, the air distribution openings are located between every two adjacent separation pieces in the axial direction, and the electric heating pipes penetrate through the separation pieces and are positioned and fixed; a vortex-shaped flow guide sheet is arranged between every two adjacent separation sheets, the inner end of each vortex-shaped flow guide sheet is close to the air pipe, the outer end of each vortex-shaped flow guide sheet extends to the inner wall of the heat preservation outer shell, and sheet bodies of the separation sheets are arranged between the multiple adjacent electric heating pipes in a penetrating mode and used for forming spiral flow guide channels in the corresponding heating intervals; and air entering the heating section through the air distribution opening flows along the spiral path and exchanges heat with the electric heating pipe. And the air heating uniformity, the heat efficiency and the operation reliability of the device are improved.

Description

Technical Field

[0001] This invention relates to an air electric heating device with a central flow splitting and spiral flow guiding structure, and relates to the field of air heating equipment technology. Background Technology

[0002] Air electric heating devices, as a common type of industrial heating equipment, are widely used in petrochemical, energy and power, environmental engineering, and electronics manufacturing fields. Their basic working principle is to utilize the heat generated by electric heating elements to exchange heat with flowing air, thereby raising the air to a predetermined temperature. To improve heating efficiency and operational safety, existing technologies mainly focus on improving the arrangement of the electric heating elements and the structure of the airflow channels.

[0003] Currently, a common technical solution involves arranging multiple heating tubes parallel to the mainstream airflow direction within the insulation shell, and installing baffles at the inlet end or inside the heating tube array to ensure uniform airflow through the gaps between the heating tubes. Air typically enters from one end of the shell, is deflected or dispersed by the baffles, and then flows out from the other end after passing through the heating tube area. Another improved solution involves designing serpentine, labyrinthine, or multi-reversal airflow structures to extend the airflow path within the heating cavity, thereby increasing the contact time between the air and the heating tubes and improving heat exchange efficiency.

[0004] However, the above-mentioned technical solutions still have significant shortcomings in practical applications. First, since air is usually introduced from one end, the heating element near the inlet first comes into contact with the low-temperature air as it flows through the entire heating cavity, resulting in a high heat exchange intensity. However, by the time the air reaches the outlet, its temperature has risen significantly, leading to a marked reduction in the heat exchange load of the heating element at the outlet. This significant temperature gradient along the airflow direction results in extremely uneven operating temperature distribution along the length of the same heating element and between heating elements at different locations. This easily leads to thermal stress concentration in localized areas, which can cause heating element deformation, solder joint cracking, or premature aging of the resistance wire during long-term operation, thereby shortening the service life of the core heating element.

[0005] Secondly, although some existing technologies guide airflow by setting up deflectors or complex duct structures, it is still difficult to achieve a truly uniform distribution of the airflow field in three-dimensional space. This easily leads to the formation of "short-circuit" airflows with excessively high velocity and insufficient contact time with the heating element, or "dead zone" vortices with excessively slow velocity and difficulty in removing heat in time. This uneven airflow distribution not only reduces the overall heating uniformity but also causes large fluctuations in the outlet air temperature, affecting the operational stability of the equipment.

[0006] Secondly, to compensate for uneven heating, existing technologies often achieve the target outlet air temperature by increasing local heating power or further extending the airflow channel. However, these measures not only increase system energy consumption but may also pose safety hazards due to localized overheating. Meanwhile, while designs relying on complex fixed airflow structures improve heat exchange efficiency to some extent, they also significantly increase airflow resistance, leading to higher fan energy consumption. Furthermore, the complex structure and high manufacturing and maintenance costs of these devices are detrimental to long-term stable operation.

[0007] Therefore, how to achieve uniform distribution of cold air within a limited space, enabling the air to fully and evenly exchange heat with the heating element, and efficiently and orderly remove the hot air after heating is completed, thereby fundamentally alleviating problems such as uneven heating, large temperature difference stress, low thermal efficiency, and insufficient reliability, has become a technical challenge that urgently needs to be overcome in this field. Summary of the Invention

[0008] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide an air electric heating device with a central flow splitting and spiral flow guiding structure. By structurally reconstructing the air flow path and heating process inside the device, uniform air distribution, gradual heating and orderly exhaust are achieved, thereby improving heating uniformity, thermal efficiency and device operation reliability.

[0009] To solve the above-mentioned technical problems, the technical solution of the present invention is: an air electric heating device with a central diversion and spiral flow guiding structure, including an insulated outer shell, a duct that runs through the axis of the insulated outer shell, a plurality of electric heating tubes disposed in the insulated outer shell and distributed in a multi-layered ring around the outside of the duct, air inlets disposed at both ends of the duct, and air outlets disposed on the side wall of the insulated outer shell. The duct wall is provided with several air distribution ports spaced apart along the axial direction to radially disperse the air entering the duct to the outside of the duct. The outer wall of the duct is fixedly provided with several partition plates at intervals along the axial direction. The adjacent partition plates form a heating zone. The air outlet is located between two axially adjacent partition plates. The electric heating tube passes through the partition plates and is positioned and fixed. A vortex-shaped guide vane is provided between two adjacent partition plates. The inner end of the vortex-shaped guide vane is close to the air duct, and the outer end extends to the inner wall of the heat insulation shell. The partition plate is inserted between multiple adjacent electric heating tubes to form a spiral guide channel in the corresponding heating zone, so that the air entering the heating zone through the air outlet flows along the spiral path and exchanges heat with the electric heating tube.

[0010] Preferably, a partition plate is fixedly installed in the middle of the air duct, which divides the interior of the air duct into two air inlet chambers arranged symmetrically along the axial direction, and the air inlets are respectively connected to the corresponding air inlet chambers.

[0011] Preferably, the spiral pitch of the vortex guide vane gradually converges at the end away from the air duct, so that the air is accelerated when it flows through the area and flows towards the air outlet along the inner wall of the heat insulation shell.

[0012] Preferably, the air outlet is located in the middle of the side wall of the heat-insulating outer shell, and is situated on the confluence path of the airflow in the heating zones on both sides of the partition plate.

[0013] Preferably, the air duct is provided with an air guiding unit, which includes a rotating shaft rotatably disposed inside the air duct and radial fan blades disposed on the rotating shaft. The radial fan blades face the inner area of ​​the air distribution port to enhance the radial dispersion effect of air in the air duct.

[0014] Preferably, axial guide vanes are provided at both ends of the rotating shaft, and the axial guide vanes are located inside the air inlet to apply axial guidance to the air entering the duct.

[0015] Preferably, the central axis of the air inlet is set lower than the central axis of the duct, so that the incoming airflow impacts the axial guide vane at an inclined angle, thereby driving the shaft to rotate under the action of the airflow.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention constructs an air distribution structure characterized by central diversion by setting a through-duct at the axis of the heat-insulating outer shell and opening air distribution ports on its duct wall. This causes the air to change from axial flow to radial uniform diffusion before entering the heating area, which structurally improves the problem of uneven air distribution in traditional air electric heating devices and provides the basic conditions for uniform heating.

[0017] 2. This invention uses a multi-layered radial arrangement of heating elements in conjunction with a central distribution structure to create a gradual heating path from the inside out during the heating process. This allows the air temperature to rise slowly, effectively reducing the temperature gradient along the length of the heating elements and between different heating elements. This reduces the risk of thermal stress concentration and improves the operational reliability and service life of the heating elements.

[0018] 3. This invention divides the heating space into axial intervals using partition plates and sets up vortex guide vanes in each interval to form a spiral guide channel, so that the air flows along an orderly spiral path in the heating interval, extending the effective heat exchange path and residence time, and improving the heat exchange sufficiency; at the same time, it guides the heated air to collect and discharge in an orderly manner along the inner wall of the shell, realizing the optimization of the entire process of air distribution, heating to discharge, and improving the thermal energy utilization efficiency.

[0019] 4. The present invention has a compact overall structure and reasonable airflow organization. Combined with the heat insulation effect of the heat-insulating shell, it reduces ineffective heat loss. In the preferred embodiment, the enhancement of the central diversion process by the wind-guided unit can further improve the stability of air distribution and achieve aerodynamic self-drive under high air volume conditions, which is conducive to reducing system operating energy consumption and improving the practicality and economy of the device.

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of an air electric heating device with a central flow splitting and spiral flow guiding structure according to the present invention; Figure 2 This is a cross-sectional structural diagram of the thermal insulation outer shell of the present invention, showing the overall layout of the central air duct, electric heating tube and heating zone; Figure 3 This is a schematic diagram of the cooperation structure between the electric heating tube and the separator in the axial heating zone of the present invention; Figure 4 This is a schematic diagram of the structure of the central air duct and its air outlets within the insulation shell of the present invention; Figure 5 This is a schematic diagram showing the relative positional relationship between the vortex-shaped guide vane and the air duct within the heating zone of the present invention; Figure 6 This is a schematic diagram showing the location of the wind-guiding unit of the present invention inside the air duct; Figure 7 This is a cross-sectional structural diagram of the duct of the present invention, showing the relative arrangement of the wind-guiding unit and the air distribution outlet; In the diagram: 1. Insulated outer shell; 2. Air duct; 21. Air outlet; 22. Partition plate; 3. Air inlet; 4. Wind guide unit; 41. Rotating shaft; 42. Radial fan blade; 43. Axial guide fan blade; 44. Motor; 5. Electric heating tube; 6. Partition plate; 7. Air outlet; 8. Vortex guide vane. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] like Figures 1-7 As shown, this embodiment provides an air electric heating device with a central flow splitting and spiral flow guiding structure, including an insulated outer shell 1 and a plurality of electric heating tubes 5 installed inside the insulated outer shell 1. The insulated outer shell 1 has a closed structure, and its interior is used to form a space for air heating and flow. A duct 2 is provided through the axial position of the insulated outer shell 1, and the duct 2 extends along the axial direction of the device to guide air into the interior of the device axially.

[0026] Multiple heating elements 5 are arranged in a ring around the outside of the air duct 2, forming a multi-layered structure from the inside to the outside in the radial direction. This allows the air entering the device to sequentially contact and exchange heat with the heating elements 5 at different levels during radial diffusion. An air outlet 7 is provided on the side wall of the insulation shell 1 to exhaust the heated air.

[0027] The outer wall of the duct 2 is provided with several air distribution ports 21 spaced apart along its axial direction. Each air distribution port 21 is used to guide the air flowing along the axial direction of the duct 2 to the heating area outside the duct 2. Through the central flow distribution structure formed by the central duct 2 and the air distribution ports 21, the air entering the duct 2 changes from axial flow to radial dispersion flow, providing the basic conditions for uniform distribution and gradual heating of air inside the device.

[0028] During the air heating process, air enters the duct 2 from the external air supply equipment through the air inlet 3, then flows axially along the duct 2 and disperses to the outside of the duct 2 through the air distributor 21. After entering the heating area through the air distributor 21, the air first contacts and exchanges heat with the inner heating element 5 closest to the duct 2, and then gradually flows outward in the radial direction, continuing to contact and exchange heat with the outer heating element 5, thus forming a gradual heating path from the inside out. This heating method allows the air temperature to rise gradually in the radial direction, which helps to reduce the temperature gradient between different heating elements along the length of the heating element 5, improving heating uniformity and the operational reliability of the heating element 5.

[0029] like Figure 1 , Figure 3 , Figure 4 , Figure 6 and Figure 7 As shown, a partition plate 22 is fixedly installed in the middle of the duct 2. The partition plate 22 divides the interior of the duct 2 into two air inlet chambers symmetrically arranged along the axial direction. Air inlets 3 are respectively provided at both ends of the duct 2, and the two air inlets 3 respectively supply air to the corresponding air inlet chambers, thereby realizing bidirectional air intake. Through the above structure, air can be simultaneously supplied from both ends of the duct 2 to the middle, making the air intake conditions of each air outlet 21 at different positions along the axial direction of the duct 2 more consistent, thereby improving the uniformity of axial air distribution and laying the foundation for the uniform distribution of the axial temperature field.

[0030] like Figures 2-4 As shown, to further optimize the airflow organization inside the device, several circular partition plates 6 are fixedly installed at axial intervals on the outer wall of the duct 2. Each partition plate 6 is located between two axially adjacent group air outlets 21, and each electric heating tube 5 is sequentially inserted into the mounting holes provided on the partition plate 6, thereby positioning and supporting the electric heating tube 5 in the axial and radial directions and maintaining a reasonable distance between adjacent electric heating tubes 5. The outer diameter of the partition plate 6 is smaller than the inner diameter of the heat insulation shell 1, so that an annular channel is formed between the outer edge of the partition plate 6 and the inner wall of the heat insulation shell 1. This annular channel is used to guide the air to gather and be discharged along the inner wall of the shell after heating is completed.

[0031] With the arrangement of the aforementioned partition 6, the heating space inside the device is divided into multiple relatively independent heating zones in the axial direction, so that the air entering through the air distribution port 21 is constrained to flow within the corresponding heating zone. Structurally, this reduces the lateral mixing and disorderly disturbance of airflow between different axial zones, allowing the airflow in each heating zone to develop relatively independently and in an orderly manner, providing a stable flow environment for the effective function of the subsequent spiral guide structure.

[0032] like Figure 2 and Figure 5 As shown, within each heating zone, a vortex-shaped guide vane 8 is arranged between two adjacent partition plates 6. The inner end of the vortex-shaped guide vane 8 is located close to the air duct 2, and its outer end extends towards the inner wall of the insulation shell 1. The overall shape of the vortex-shaped guide vane 8 is used to form a continuous spiral guide channel within the corresponding heating zone. Part of the structure of the vortex-shaped guide vane 8 passes through the gap between adjacent electric heating tubes 5, so that the electric heating tubes 5 are orderly embedded in the spiral flow channel.

[0033] Air entering the heating zone radially through the central air duct 2 via the air distribution port 21 flows along a spiral path within the heating zone under the guidance of the vortex guide vanes 8. This spiral guide structure forcibly alters the airflow direction and velocity distribution, extending the effective flow path and residence time of the air within the heating zone. Furthermore, it allows the air to undergo multiple and thorough heat exchange processes with the surfaces of the multiple heating tubes 5 during its flow, thereby improving the heat absorption efficiency per unit volume of air.

[0034] When air flows along the spiral guide path to the outer end of the vortex guide vane 8, the airflow is guided tangentially along the inner wall of the insulation shell 1 by the curved guide structure at its end, and further converges to the air outlet 7 for discharge. Through the above-mentioned airflow guidance method, hot air can be effectively prevented from accumulating in the core area of ​​the heating zone or flowing back to the vicinity of the electric heating tube 5, affecting subsequent air heating. At the same time, the airflow is guided to be discharged in an orderly manner according to the preset path, realizing the continuous renewal of airflow in the heating zone.

[0035] like Figure 5 As shown, the spiral pitch of the vortex guide vane 8 gradually decreases at the end furthest from the duct 2, causing the cross-sectional area through which air can pass to gradually shrink, thus structurally accelerating the airflow. Through this pitch variation design, the air has sufficient kinetic energy after leaving the vortex guide vane 8, enabling it to flow stably along the inner wall of the insulation shell 1 towards the air outlet 7, preventing airflow stagnation or swirling at the end of the heating zone, and simultaneously enhancing the convective heat transfer intensity in this area.

[0036] like Figures 1-3 As shown, the air outlet 7 is located on the side wall of the insulation shell 1 and in the middle of the partition plate 22. Since the partition plate 22 divides the internal heating space into two symmetrical heating areas in the axial direction, the ends of the vortex guide vanes 8 on both sides of the partition plate 22 are bent in opposite directions, causing the airflow from the two heating areas to converge and flow towards the air outlet 7 in the middle area of ​​the insulation shell 1. By arranging the air outlet 7 on the confluence path of the airflow, the flow distance of the hot air after leaving the heating area can be shortened, reducing flow resistance and heat loss, thereby improving exhaust smoothness and overall flow efficiency.

[0037] like Figure 6 and Figure 7As shown, in this embodiment, a wind-guiding unit 4 can also be installed inside the duct 2 to enhance the air dispersion effect within the central duct 2. The wind-guiding unit 4 includes a rotating shaft 41 rotatably installed inside the duct 2. The rotating shaft 41 passes through the partition plate 22 and is supported by the partition plate 22. On the rotating shaft 41 on both sides of the partition plate 22, several sets of radial fan blades 42 are arranged axially, and each radial fan blade 42 is respectively arranged in the inner area of ​​the air distribution port 21. When the rotating shaft 41 is driven by the motor 44, the radial fan blades 42 apply centrifugal force to the air in the duct 2, causing the air to actively deflect towards the inner wall of the duct 2, thereby promoting the uniform outward dispersion of air through each air distribution port 21 and improving the stability of the radial flow distribution process.

[0038] like Figure 7 As shown, axial guide vanes 43 can also be installed at both ends of the rotating shaft 41, located inside the air inlet 3, to apply axial guidance to the airflow when the rotating shaft 41 rotates, assisting the air to enter the mid-to-far section region along the axial direction of the duct 2, ensuring that the air can reach each air distribution port 21. In a preferred embodiment, the central axis of the air inlet 3 is slightly offset relative to the central axis of the duct 2, so that the airflow entering the duct 2 impacts the axial guide vanes 43 at a certain angle, thereby directly driving the rotating shaft 41 to rotate when the airflow is large, realizing the aerodynamic self-drive of the wind-guided unit 4, so as to reduce energy consumption. It should be noted that the wind-guided unit 4 is a preferred enhanced structure of the present invention, and its setting is used to further improve the central diversion effect, but does not constitute a necessary condition for realizing the core technical solution of the present invention.

[0039] A method for operating an air electric heating device with a central flow splitting and spiral flow guiding structure includes the following steps: 1. Axial air delivery stage: The external air supply equipment delivers air into the air duct through the air inlets at both ends, and the axial guide vanes assist the airflow in being delivered axially to each air outlet area; if the air inlet is offset, the airflow can directly drive the rotating shaft to rotate and start the wind-guided unit.

[0040] 2. Central radial flow distribution stage: Air flows axially along the duct and is radially dispersed to the outer heating area through the air distribution port; the radial fan blades of the wind guide unit rotate to generate centrifugal force, which further promotes the uniform distribution of air to each heating zone.

[0041] 3. Gradual radial heating stage: After air enters the heating area, it flows from the inside to the outside through the inner and outer heating tubes, gradually completing the heat exchange. The temperature rises slowly along the radial direction, forming a stable gradual heating path.

[0042] 4. Spiral Guided Flow Enhanced Heat Exchange Stage: In each heating zone, the vortex guide vanes guide the air to flow along the spiral path, forcing the air to contact the heating tube multiple times for heat exchange, extending the residence time and improving the heat absorption efficiency; the reduced pitch at the end of the guide vanes accelerates the airflow and avoids the stagnation of hot air.

[0043] 5. Convergence and Discharge Stage: The heated air flows tangentially along the inner wall of the insulation shell, gathers in the central convergence area, and is discharged through the air outlet, completing the entire heating cycle.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. An air electric heating device with a central diversion and spiral flow guiding structure, comprising an insulated outer shell (1), a duct (2) passing through the axis of the insulated outer shell (1), a plurality of electric heating tubes (5) disposed inside the insulated outer shell (1) and arranged in a multi-layered, surrounding manner on the outside of the duct (2), air inlets (3) disposed at both ends of the duct (2), and air outlets (7) disposed on the side wall of the insulated outer shell (1), characterized in that: The duct (2) has several air distribution ports (21) spaced apart along the axial direction on its wall, which are used to radially disperse the air entering the duct (2) to the outside of the duct (2); The outer wall of the duct (2) is fixedly provided with a number of partition plates (6) at intervals along the axial direction. The adjacent partition plates (6) form a heating zone. The air outlet (21) is located between two axially adjacent partition plates (6). The electric heating tube (5) passes through the partition plate (6) and is positioned and fixed. A vortex guide plate (8) is provided between two adjacent partition plates (6). The inner end of the vortex guide plate (8) is close to the air duct (2), and the outer end extends to the inner wall of the heat insulation shell (1). The plate body of the partition plate (6) is inserted between multiple adjacent electric heating tubes (5) to form a spiral guide channel in the corresponding heating zone, so that the air entering the heating zone through the air outlet (21) flows along the spiral path and exchanges heat with the electric heating tubes (5).

2. The air electric heating device with a central flow splitting and spiral flow guiding structure according to claim 1, characterized in that: A partition plate (22) is fixedly installed in the middle of the air duct (2). The partition plate (22) divides the interior of the air duct (2) into two air inlet chambers arranged symmetrically along the axial direction. The air inlet (3) is connected to the corresponding air inlet chamber.

3. The air electric heating device with a central flow splitting and spiral flow guiding structure according to claim 1, characterized in that: The spiral pitch of the vortex guide vane (8) gradually converges at the end away from the air duct (2) so that the air is accelerated when it flows through the area and flows towards the air outlet (7) along the inner wall of the heat-insulating outer shell (1).

4. The air electric heating device with a central flow splitting and spiral flow guiding structure according to claim 2, characterized in that: The air outlet (7) is located in the middle of the side wall of the heat-insulating outer shell (1) and is located on the confluence path of the airflow in the heating zone on both sides of the partition plate (22).

5. The air electric heating device with a central flow splitting and spiral flow guiding structure according to claim 1, characterized in that: The air duct (2) is provided with an air guiding unit (4). The air guiding unit (4) includes a rotating shaft (41) rotatably disposed in the air duct (2) and a radial fan blade (42) disposed on the rotating shaft (41). The radial fan blade (42) faces the inner area of ​​the air distribution port (21) and is used to enhance the radial dispersion effect of air in the air duct (2).

6. The air electric heating device with a central flow splitting and spiral flow guiding structure according to claim 5, characterized in that: The two ends of the rotating shaft (41) are provided with axial guide vanes (43), which are located inside the air inlet (3) and are used to apply axial guidance to the air entering the air duct (2).

7. The air electric heating device with a central flow splitting and spiral flow guiding structure according to claim 5, characterized in that: The central axis of the air inlet (3) is set to be lower than the central axis of the air duct (2) so that the incoming airflow impacts the axial guide vane (43) at an inclined angle, thereby driving the rotating shaft (41) to rotate under the action of the airflow.

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