Chimney damper

Abstract

The application relates to the technical field of industrial chimneys, and discloses an external liquid damper. The device is composed of an annular support body fixed to the outer wall of a chimney and dampers uniformly distributed on the annular support body; each damper is a closed box body, a horizontal porous plate is arranged in the box body, the box body is filled with damping liquid, and the liquid level is calibrated to be flush with the upper surface of the porous plate. When the chimney is shaken by wind or an earthquake, the damping liquid reciprocally flows through the holes and shears and partially loses with the hole wall, thereby forming high-efficiency energy consumption and significantly reducing displacement and acceleration response. Preferably, upper and lower double-layer box bodies are adopted, and the liquid levels can be independently adjusted and calibrated; the box body is provided with a liquid injection pipe and a venting opening, thereby facilitating construction and maintenance; and light damping particles can be added to the liquid surface to enhance disturbance of the free surface. The device is simple in structure, small in additional mass and convenient to install, is particularly sensitive to small-amplitude low-frequency vibration, and is suitable for reinforcing newly-built and existing chimneys.

Description

Technical Field

[0001] This application belongs to the field of industrial chimney technology, and in particular relates to a chimney damper. Background Technology

[0002] Tall chimneys are prone to large lateral displacement and acceleration responses under wind loads, earthquakes, and vortex-induced vibrations. Long-term vibration can lead to problems such as local cracking of masonry or steel cylinders, fatigue of equipment anchor bolts, and damage to auxiliary components. Existing external dampers are mostly viscous dampers, tuned mass dampers, or cavity liquid dampers, but they have shortcomings such as (1) large added mass of the structure and high maintenance costs; (2) insufficient contact between the liquid and internal components, resulting in limited energy dissipation efficiency; and (3) inconvenience in construction and maintenance. Therefore, there is an urgent need for a chimney damping device that is simple in structure, easy to install, and can efficiently dissipate energy even under small displacement conditions. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a chimney damper that addresses the shortcomings of the prior art by optimizing the contact and flow path between the liquid and the perforated plate, thereby improving the synergistic energy dissipation capacity of liquid shearing and pore friction, and thus reducing the chimney sway amplitude and acceleration response.

[0004] The technical solution adopted by this utility model to solve its technical problem is: A chimney damper includes an annular support body fixedly connected to the outer wall of a chimney, wherein multiple sets of dampers are radially and uniformly arranged on the annular support body. The damper includes a housing, a perforated plate is disposed inside the housing, and damping fluid is filled into the inner cavity of the housing, with the damping fluid flush with the upper surface of the perforated plate.

[0005] Preferably, the chimney damper of this utility model is configured as a double-layer box structure.

[0006] Preferably, in a chimney damper of the present invention, each injection chamber of the housing is provided with an injection pipe for injecting damping fluid.

[0007] Preferably, in the chimney damper of this utility model, the housing is configured as an annular shape.

[0008] Preferably, in the chimney damper of this utility model, the housing is configured as a rectangular ring structure.

[0009] Preferably, in a chimney damper of the present invention, damping particles are disposed inside the housing and the damping particles float on the surface of the damping liquid.

[0010] Preferably, in the chimney damper of this utility model, the thickness of the perforated plate is not less than 2mm.

[0011] The beneficial effects of this utility model are: (1) The damping fluid level is set to be flush with the upper surface of the orifice plate. When the chimney experiences small to medium amplitude swaying, the damping fluid immediately forms sufficient and repeated flow and shear coupling with the orifice plate holes. The local loss, eddy current and viscous resistance of the liquid passing through the pores are significantly amplified, thereby reducing the degree of chimney swaying. (2) The upper and lower double-layer box can form a "series-parallel" composite flow path, expanding the equivalent damping range; (3) Optional damping particles can enhance liquid surface disturbance and vortex dissipation, further improving energy consumption under high amplitude conditions. Attached Figure Description

[0012] The technical solution of this application will be further described below with reference to the accompanying drawings and embodiments.

[0013] Figure 1 This is a schematic diagram of the damper installation (vertical) state in Embodiment 1 or 2 of this application; Figure 2 This is a schematic diagram (top view) of the distribution of the annular damper in Embodiment 1 of this application; Figure 3 This is a schematic diagram (top view) of the distribution of the annular rectangular damper in Embodiment 2 of this application; The attached figures are labeled as follows: 10—Chimney; 20—Annular support; 30—Damper; 31—Box; 32—Perforated plate; 33—Injection pipe. Detailed Implementation

[0014] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0015] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0016] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

[0017] The technical solution of this application will now be described in detail with reference to the accompanying drawings and embodiments.

[0018] Example 1: This example provides a chimney damper. An annular support 20 is fixedly connected to the outer wall of the chimney 10 via welded clamps. Multiple dampers 30 are arranged at equal angles along the circumference. Each damper 30 is a sealed box 31, with a horizontally placed perforated plate 32 inside. Damping fluid is injected into the box 31, and the fluid level is calibrated to be strictly flush with the upper surface of the perforated plate 32, verified by an elevation scale and observation window. When the chimney experiences lateral swaying under wind or earthquake conditions, the box generates relative acceleration, causing the fluid to flow back and forth through the perforations of the perforated plate. The fluid undergoes localized rapid contraction and re-expansion through the holes, which, combined with the viscosity of the hole walls and fluid surface disturbance, causes significant energy dissipation, thereby reducing the structural response.

[0019] Perforated plate design parameters: Open area ratio 10%-45%, preferably 20%-35%; single hole diameter 10-40mm or equivalent oblong hole; plate thickness 2-10mm; material options include stainless steel or corrosion-resistant aluminum alloy. Damping fluid options include silicone oil, glycerin aqueous solution, or antifreeze water-based fluid; kinematic viscosity 10-200cSt, determined according to the target frequency band.

[0020] Liquid level control: Precise calibration is achieved by using the injection pipe 33 in conjunction with the overflow / vent port, so that the liquid level is flush with the upper surface of the porous plate with an allowable deviation of ≤±1mm.

[0021] like Figure 3 As shown, the damper 30 adopts a double-layer box structure. Each layer 31 is annular, with a perforated plate 32 coaxially arranged. Each layer is equipped with an injection pipe 33 and an observation window, facilitating independent adjustment of the liquid level for each layer. The upper end of the injection pipe 33 is tightly sealed with a cap to maintain the sealing of the injection chamber and prevent the damping fluid from evaporating and being consumed. The annular shape is conducive to forming a uniform circumferential flow channel and an axisymmetric inertial distribution, making it suitable for placement on the outer wall of a circular chimney.

[0022] Working effect: The annular channel enables continuous reciprocating flow of liquid along the circumferential direction. During the phase transition of the liquid above and below the orifice plate, rapid directional changes occur, resulting in stable local losses and shear energy dissipation. Experiments / simulations show that, under the same volume conditions, the annular shape achieves a more uniform damping distribution and less local stress concentration.

[0023] Example 2: Figure 3 As shown, the damper 30 has a rectangular ring structure. The perforated plate 32 is horizontally positioned, flush with the liquid surface. Several reinforcing ribs can be arranged within each straight-edge section to control the plate deflection. The rectangular ring structure facilitates installation on chimney sections supported by platforms or straight beams, and also facilitates modular assembly.

[0024] Working effect: The rectangular annular zigzag flow path increases the equivalent stroke of the liquid and the energy dissipation path, which has a stronger energy dissipation capacity for low-frequency large displacement conditions.

[0025] Example 3: In any one or two layers of the tank in Example 1 or 2, damping particles with a density lower than that of the liquid are added to the liquid surface, such as hollow polymer microspheres or closed-cell rubber particles. The particles move relative to each other on the liquid surface with the sloshing, enhancing the generation of free surface waves and eddies, increasing interfacial shear and collision dissipation, which is suitable for high-energy input conditions such as storms or strong earthquakes.

[0026] Based on the above-described preferred embodiments according to this application, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this application. The technical scope of this application is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A chimney damper, comprising an annular support (20) fixedly connected to the outer wall of a chimney (10), characterized in that, Multiple sets of dampers (30) are radially and uniformly arranged on the annular support (20); The damper (30) includes a housing (31), a perforated plate (32) is provided inside the housing (31), and the inner cavity of the housing (31) is filled with damping fluid, which is flush with the upper surface of the perforated plate (32).

2. A chimney damper according to claim 1, characterized in that, The damper (30) is configured as a double-layer box structure.

3. A chimney damper according to claim 2, characterized in that, Each injection chamber of the box (31) is equipped with an injection pipe for injecting damping fluid.

4. A chimney damper according to any one of claims 1-3, characterized in that, The box (31) is configured as a ring.

5. A chimney damper according to any one of claims 1-3, characterized in that, The box is designed as a rectangular ring structure.

6. A chimney damper according to claim 1, characterized in that, The box (31) contains damping particles that float on the surface of the damping liquid.

7. A chimney damper according to claim 1, characterized in that, The thickness of the perforated plate (32) is not less than 2 mm.

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