Flue guide structure

Abstract

The present application discloses a flue flow guide structure, comprising an outer frame and a plurality of flow guide plates. The outer frame is fixed to the inner wall of the flue and forms a hollow channel. The flow guide plates are arranged in the hollow channel and collectively form a flow guide area. Each flow guide plate is provided with a flow slowing part corresponding to the position of the outer periphery of the flow guide area. The orthographic projection of the flow slowing part at least partially falls into the flow guide area, dividing the flow guide area into a peripheral buffer zone and a central advection zone. An air hole is provided on the flow slowing part. A plurality of the flow guide structures can be arranged in the flue along the direction of the flue gas flow. The windward side of each flow guide structure is provided with a booster plate covering the flow guide area. The flow guide plate as a whole adopts an airfoil streamline structure. The wall surface thereof facing the flow guide area is provided with a rib extending along the direction of the flue gas flow. The present application can realize the partitioned flow slowing, uniform pressure boosting and smooth flow guiding of the flue gas, effectively improve the flue flow field distribution, eliminate vortex and deflection, reduce the flow resistance and equipment scouring, and improve the operation efficiency and stability of the flue gas system.

Description

Technical Field

[0001] This application relates to the technical field of flue gas emissions, and in particular to a flue gas guiding structure. Background Technology

[0002] In flue gas emission systems such as industrial boilers, incinerators, and desulfurization and denitrification systems, the flow efficiency of flue gas directly affects heat exchange efficiency, dust removal effect, equipment operation stability, and energy consumption level. To optimize the flue gas flow field, related technologies typically incorporate flow guiding structures within the flue, using fixed or adjustable guide plates to guide the flow of flue gas and avoid problems such as eddies and flow deviations caused by pipe bends, abrupt interface changes, or uneven airflow velocity.

[0003] The problem with the relevant technology is that when flue gas flows in the flue, the peripheral airflow is prone to forming a high-speed jet due to the boundary effect, which directly impacts the inner wall of the flue. Over time, this can lead to increased wear and corrosion of the inner wall, and even cause flue vibration and noise, which can seriously affect the structural safety of the flue. Furthermore, since the guide plates are mostly flat or simple arc-shaped designs, they cannot effectively buffer the high-speed flue gas on the periphery of the guide area. The speed difference between the high-speed flue gas and the central airflow can easily generate eddies. After the eddies rebound, they will further aggravate the secondary impact on the inner wall of the flue, while also disrupting the stability of the flow field and affecting the flue gas flow efficiency. Summary of the Invention

[0004] In order to reduce the impact of flue gas on the flue during the emission process and to ensure the flue gas flow efficiency, this application provides a flue gas guiding structure.

[0005] The flue gas guiding structure provided in this application adopts the following technical solution:

[0006] A flue gas flow guiding structure includes an outer frame and multiple guide plates. The outer frame is fixed to the inner wall of the flue and has a hollow channel. The multiple guide plates are spaced apart in the hollow channel and connected to the outer frame. The guide plates together form a flow guiding area. The structure is characterized in that: each guide plate has a flow-slowing section, which is located on the portion of each guide plate corresponding to the outer periphery of the flow guiding area. The orthographic projection of the flow-slowing section at least partially falls within the flow guiding area to block and slow down the flue gas, thereby dividing the flow guiding area into an outer buffer zone and a central horizontal flow zone. Ventilation holes are provided on the portion of the flow-slowing section where the orthographic projection falls within the flow guiding area. The ventilation holes are used to allow the blocked and slowed flue gas to be discharged in an orderly manner.

[0007] Optionally, the flow-retarding section includes a first part and a second part. The first part of the flow-retarding section is disposed on the two outermost guide plates, and the second part of the flow-retarding section is disposed at both ends of the remaining guide plates along their length.

[0008] Optionally, the first portion of the flow-retarding section extends along the length of the guide plate, and the extension length is the same as the length of the guide plate;

[0009] The second part of the flow-slowing section extends along the length of the guide plate and covers the corresponding flow-guiding areas on both sides of the guide plate, so that the outer perimeter of the flow-guiding area forms an outer buffer zone with a consistent annular diameter, ensuring that the flue gas velocity in the outer buffer zone is uniform.

[0010] Optionally, one end of the flow-retarding section is integrally connected to the leeward side of the guide plate, and the other end extends into the flow-guiding area in an arc shape, with the arc opening of the arc-shaped flow-retarding section facing the windward side of the guide plate.

[0011] Optionally, multiple flow guiding structures are provided at intervals along the flow direction of the flue gas in the flue. Each flow guiding structure also includes a pressure plate. The pressure plate is fixed to the windward side of the flow guiding structure and covers the flow guiding area. Several pressure-boosting holes are opened on the pressure plate. Each pressure-boosting hole is connected to the flow guiding area, and the orifice size at one end of the pressure-boosting hole connected to the flow guiding area is smaller than the orifice size at the other end.

[0012] Optionally, the pressure boosting hole is a tapered hole or a shrinkage hole, with its diameter decreasing linearly from the larger end to the smaller end, and the connection between the hole at both ends of the pressure boosting plate and the pressure boosting plate is a smooth transition with rounded corners.

[0013] Optionally, a flange is provided at one end of the outer frame, and the outer frame is fixedly installed on the inner wall of the flue through the flange. The pressure plate and each guide plate are fixedly connected to the outer frame, and the leeward side of the pressure plate and the windward side of each guide plate are spaced apart.

[0014] Optionally, the windward side of the pressure plate is provided with a flow guiding ring plate. The end of the flow guiding ring plate away from the pressure plate is inclined outward in the direction away from the flow guiding area, and this end is in close contact with the inner wall of the flue to guide the flue gas in the flue to converge into the pressure boosting hole of the pressure plate.

[0015] Optionally, the guide vane has an overall airfoil-shaped streamlined structure, and several ribs are spaced apart on the wall surface of each guide vane facing the guide area, with the ribs extending along the flue gas flow direction.

[0016] In summary, this application includes at least one of the following beneficial technical effects:

[0017] 1. By setting flow-damping sections on each guide plate, with the orthogonal projection of the flow-damping section falling within the guide area, the high-speed flue gas on the outer periphery of the guide area can be directly blocked, slowing down and buffering it, thus reducing the flue gas velocity on the outer periphery and significantly reducing the impact performance of the flue gas. Meanwhile, the middle advection zone has no excessive obstruction from the flow-damping section, allowing the flue gas to maintain a relatively fast flow velocity and pass smoothly, ensuring that the flue gas flow efficiency is not affected. At the same time, due to the difference in flue gas velocity between the outer buffer and the middle advection zone, under the action of the pressure difference, the flue gas on the outer periphery, after being buffered and slowed down, will actively move towards the middle advection zone, avoiding the formation of a wall-attached jet along the inner wall of the flue, further avoiding the direct impact of high-speed flue gas on the inner wall of the flue and the secondary impact caused by eddy rebound.

[0018] 2. The flow-retarding section consists of the first and second parts, which are adapted to the layout requirements of the guide vanes at different positions, ensuring that the outer buffer zone has a consistent ring diameter, ensuring uniform flue gas velocity on the outer perimeter, and avoiding localized impact concentration. At the same time, the vents on the flow-retarding section allow the buffered flue gas to be discharged in an orderly manner, preventing flue gas stagnation or increased resistance due to obstruction. Combined with the airfoil-like streamlined design of the guide vanes and the ribs extending in the flue gas flow direction, the aerodynamic performance is further optimized, reducing airflow separation and eddy loss, lowering flue gas resistance, and ensuring smooth flue gas flow.

[0019] 3. By setting up pressurizing plates in the flow guiding structures spaced apart along the flue gas flow direction, the conical or reduced-width hole design of the pressurizing plates pre-pressurizes and rectifies the flue gas, improving airflow stability and reducing irregular impacts caused by flow field turbulence; the flow guiding ring plate guides the dispersed airflow to converge towards the pressurizing hole, preventing the flue gas from escaping along the inner wall to form a high-speed jet, further reducing the risk of impact. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the main structure of the flow guiding structure in the embodiment of this application.

[0021] Figure 2 This is a schematic diagram of the main exploded structure of the flow guiding structure in the embodiment of this application.

[0022] Figure 3 This is a cross-sectional structural diagram of the flue in an embodiment of this application.

[0023] Figure 4 yes Figure 3 A magnified schematic diagram of the structure at point A in the middle.

[0024] Reference numerals: 1. Outer frame; 2. Guide plate; 21. Flow buffer section; 211. First part; 212. Second part; 22. Vent hole; 23. Rib; 3. Outer buffer zone; 4. Middle horizontal flow zone; 5. Pressure plate; 51. Pressure hole; 6. Flange; 7. Drainage ring plate. Detailed Implementation

[0025] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0026] This application discloses a flue gas guiding structure, mainly used in industrial flue gas systems such as power plant boilers, industrial kilns, and chemical reaction units, to reduce the impact of flue gas on the inner wall of the flue while ensuring flue gas flow efficiency. (Refer to...) Figure 1 A flue gas guiding structure includes an outer frame 1 and multiple guide plates 2. The outer frame 1 is an annular frame structure with an outer diameter that matches the inner diameter of the flue. One end of the outer frame 1 is integrally formed with a flange 6. The flange 6 has circumferentially evenly distributed mounting holes. Bolts are passed through the mounting holes and fixedly connected to the mounting seats preset on the inner wall of the flue, ensuring a stable assembly and reliable sealing, and preventing flue gas from leaking from the gap between the outer frame 1 and the inner wall of the flue.

[0027] The outer frame 1 has a hollow channel reserved inside, and multiple guide plates 2 are arranged at intervals in the hollow channel. Both ends of the guide plates 2 are welded and fixed to the inner sidewall of the outer frame 1. The guide plates 2 together and the guide plates 2 and the outer frame 1 together form a guide area, and the flue gas flows from upstream to downstream of the flue along the guide area.

[0028] Reference Figure 2 The guide vane 2 has an overall airfoil-like streamlined structure to optimize aerodynamic performance, reduce airflow separation and vortex losses, and ensure smooth flue gas flow. Multiple guide vanes 2 are evenly arranged radially or axially along the outer frame. Each guide vane 2 has a flow-slowing section 21. The flow-slowing section 21 is located on the outer periphery of the flow-guiding area of ​​each guide vane 2, and the orthographic projection of the flow-slowing section 21 at least partially falls within the flow-guiding area. The flow-guiding area is divided into an outer buffer zone 3 and a central advection zone 4 by the flow-slowing section 21.

[0029] Specifically, the flow buffer 21 includes a first part 211 and a second part 212, adapted to the layout requirements of the guide vanes 2 at different positions. The first part 211 is disposed on the two outermost guide vanes 2, extending along the length of the guide vanes 2 with the same extension length as the guide vanes 2, ensuring that the outer periphery of the corresponding flow guiding area of ​​the outermost guide vanes 2 is covered; the second part 212 is disposed at both ends of the length of the remaining guide vanes 2, extending along the length of the guide vanes 2 and covering the corresponding flow guiding areas on both sides of the guide vanes 2, ultimately forming an outer buffer zone 3 with a uniform annular diameter around the flow guiding area, ensuring uniform flue gas velocity in the outer buffer zone 3 and avoiding localized impact concentration.

[0030] The flow-slowing section 21 can be configured as an arc or a straight plate. When the flow-slowing section 21 is arc-shaped, one end is integrally connected to the leeward side of the guide plate 2, and the other end extends into the flow-guiding area, with the arc facing the windward side of the guide plate 2. The arc-shaped structure can smoothly guide the flue gas to deflect to the center of the flow-guiding area, reducing the obstruction resistance of the flow-slowing section 21 to the flue gas. When the flow-slowing section 21 is straight, one end is integrally connected to the leeward side of the guide plate 2, and the other end is inclined towards the flow-guiding area in a direction away from the windward side of the guide plate 2. The inclination angle is preferably 15°-30° (which can be adjusted according to the flue gas velocity; the higher the velocity, the smaller the inclination angle to avoid excessive resistance). By blocking the flue gas with a straight line, the flow-guiding section 2 is decelerated. At the same time, the inclination angle is used to guide the flue gas to converge towards the center, which is suitable for working conditions with medium flue gas velocity and requirements for cost control.

[0031] Furthermore, several ribs 23 are spaced apart on the wall surface of each guide plate 2 facing the guide area. The ribs 23 extend along the flue gas flow direction and are integrally formed with the guide plate 2 or fixed by welding. The ribs 23 can enhance the structural strength of the guide plate 2, making it less prone to deformation under the impact of high temperature and high flow velocity flue gas; on the other hand, they can further guide the airflow to flow in an orderly manner, reduce local eddy losses, and optimize the stability of the flow field.

[0032] Reference Figure 3 To achieve long-flow guidance of flue gas within the flue, multiple flow-guiding structures are spaced apart along the flow direction of the flue gas. A pressure-boosting plate 5 is added to the windward side of each flow-guiding structure, and the pressure-boosting plate 5 is fixed to the windward side of the flow-guiding structure and completely covers the flow-guiding area. The edge of the pressure-boosting plate 5 is welded and fixed to the inner wall of the outer frame 1, and the leeward side of the pressure-boosting plate 5 is spaced apart from the windward side of each flow-guiding plate 2, reserving buffer space for the flue gas.

[0033] A plurality of pressurizing holes 51 are provided on the pressurizing plate 5. Each pressurizing hole 51 is connected to the guide area, and the orifice size of the pressurizing hole 51 at one end connected to the guide area is smaller than the orifice size at the other end. In this embodiment, the pressurizing plate 51 is preferably a conical hole, the diameter of which decreases linearly from the end with the larger orifice size (windward end) to the end with the smaller orifice size (leeward end, i.e., the guide area side). The connection between the orifices at both ends of the pressurizing plate 5 and the pressurizing plate 5 is a smooth transition with rounded corners to avoid dead angles of airflow impact. Through the design of the pressurizing holes 51, the flue gas entering the guide area can be pre-pressurized and rectified, improving airflow stability and reducing irregular impacts caused by airflow turbulence.

[0034] Furthermore, a flow-guiding ring plate 7 is integrally connected to the circumferential side of the pressure plate 5. The end of the flow-guiding ring plate 7 away from the pressure plate 5 is inclined outward in the direction away from the flow-guiding area, with an inclination angle of 30°-45°, and this end is in close contact with the inner wall of the flue (which can be achieved by welding or by using an elastic sealing gasket). The flow-guiding ring plate 7 can guide the dispersed flue gas in the flue to accurately converge into the pressure-boosting holes 51 of the pressure plate 5, preventing the flue gas from escaping along the inner wall of the flue or forming dead zones, ensuring that more flue gas is pressurized and accelerated through the pressure-boosting holes 51, while reducing the impact of the wall jet, thus forming a functional synergy with the pressure plate 5.

[0035] The implementation principle of a flue gas guiding structure in this application embodiment is as follows: When the flue gas flows from the upstream of the flue and passes through the first set of guiding structures, it is first guided by the flow guide ring plate 7 to converge into the pressure boosting hole 51 of the pressure boosting plate 5, thus preventing it from escaping along the wall surface; then the flue gas passes through the conical pressure boosting hole 51, and due to the reduction in cross-sectional area, the gas pressure increases, the flow velocity increases, and the first stage of acceleration is completed. At the same time, the pressure boosting hole 51 pre-rectifies the flue gas to improve the airflow stability, and then it enters the guiding area;

[0036] When the flue gas flows through the outer periphery of the guide area, it is slowed down by the obstruction of the slow flow section 21, which significantly reduces the flue gas velocity in the outer periphery and greatly weakens its impact kinetic energy, reducing the direct impact on the inner wall of the flue from the source; the ventilation holes 22 on the slow flow section 21 allow the flue gas that has been buffered and slowed down to be discharged in an orderly manner, avoiding the formation of resistance due to flue gas stagnation.

[0037] The central part of the guide zone is free from excessive obstruction by the slow-flow section 21, and the flue gas, accelerated by the pressure boosting hole 51, maintains a relatively fast flow rate and passes smoothly here, ensuring overall flue gas flow efficiency. Due to the slow flue gas velocity in the outer buffer zone 3 and the fast flue gas velocity in the central advection zone 4, a natural pressure difference is formed between the two. Under the action of this pressure difference, the flue gas that has been buffered and slowed down on the periphery will actively move towards the central advection zone, completely eliminating the direct impact of high-speed flue gas on the inner wall and the secondary impact of vortex rebound.

[0038] When the flue gas flows to each group of guiding structures, the above process is repeated. Each group of pressurizing plates 5 achieves a staged pressurization, continuously compensating for the velocity decay during the flue gas flow process, so that the flue gas always maintains a high velocity and stable flow field state throughout the flue section, thereby enhancing the guiding effect and ensuring the overall flue gas flow efficiency.

[0039] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A flue gas flow guiding structure, comprising an outer frame and multiple flow guiding plates, wherein the outer frame is fixed to the inner wall of the flue and has a pre-reserved hollow channel, the multiple flow guiding plates are spaced apart within the hollow channel and connected to the outer frame, and the flow guiding plates and the flow guiding plates together constitute a flow guiding area, characterized in that: Each of the aforementioned guide plates has a flow-slowing section, which is located on the portion of each guide plate corresponding to the outer periphery of the flow-guiding area. The orthographic projection of the flow-slowing section falls at least partially within the flow-guiding area to block and slow down the flue gas, thereby dividing the flow-guiding area into an outer buffer zone and a central horizontal flow zone. Ventilation holes are provided in the portion of the flow-slowing section where the orthographic projection falls within the flow-guiding area. The ventilation holes are used to allow the flue gas that has been blocked and slowed down to be discharged in an orderly manner.

2. The flue gas flow guiding structure according to claim 1, characterized in that: The flow-retarding section includes a first part and a second part. The first part of the flow-retarding section is disposed on the two outermost guide plates, and the second part of the flow-retarding section is disposed at both ends of the remaining guide plates along their length.

3. The flue gas flow guiding structure according to claim 2, characterized in that: The first portion of the flow-retarding section extends along the length of the guide plate, and the extension length is the same as the length of the guide plate; The second part of the flow-slowing section extends along the length of the guide plate and covers the corresponding flow-guiding areas on both sides of the guide plate, so that the outer perimeter of the flow-guiding area forms an outer buffer zone with a consistent annular diameter, ensuring that the flue gas velocity in the outer buffer zone is uniform.

4. The flue gas flow guiding structure according to claim 1, characterized in that: One end of the flow-retarding section is integrally connected to the leeward side of the guide plate, and the other end extends into the flow-guiding area in an arc shape, with the arc opening of the arc-shaped flow-retarding section facing the windward side of the guide plate.

5. The flue gas flow guiding structure according to claim 1, characterized in that: Multiple flow guiding structures are spaced apart in the flue along the flow direction of the flue gas. Each flow guiding structure also includes a pressure plate. The pressure plate is fixed to the windward side of the flow guiding structure and covers the flow guiding area. Several pressure-boosting holes are opened on the pressure plate. Each pressure-boosting hole is connected to the flow guiding area, and the orifice size at one end of the pressure-boosting hole connected to the flow guiding area is smaller than the orifice size at the other end.

6. The flue gas flow guiding structure according to claim 5, characterized in that: The pressure boosting hole is a tapered hole or a shrinkage hole, and its diameter decreases linearly from the larger end to the smaller end. The connection between the hole at both ends of the pressure boosting plate and the pressure boosting plate is a smooth rounded corner.

7. The flue gas flow guiding structure according to claim 5, characterized in that: A flange is provided at one end of the outer frame, and the outer frame is fixedly installed on the inner wall of the flue through the flange. The pressure plate and each guide plate are fixedly connected to the outer frame, and the leeward side of the pressure plate and the windward side of each guide plate are spaced apart.

8. The flue gas flow guiding structure according to claim 5, characterized in that: The pressure plate has a flow guiding ring plate circumferentially arranged on the windward side. The end of the flow guiding ring plate away from the pressure plate is inclined outward in the direction away from the flow guiding area, and this end is in close contact with the inner wall of the flue to guide the flue gas in the flue to converge into the pressure boosting hole of the pressure plate.

9. The flue gas flow guiding structure according to claim 1, characterized in that: The guide vane has an overall airfoil-shaped streamlined structure, and several ribs are spaced apart on the wall surface of each guide vane facing the guide area, with the ribs extending along the flue gas flow direction.

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