A type of silencer duct

Abstract

This invention provides a sound-absorbing duct, belonging to the field of building ventilation technology. The sound-absorbing duct includes a straight section and a curved section, connected together by a flange mechanism. The curved section contains multiple gas-guiding sound-absorbing plates, with adjacent plates forming a horn-shaped structure with one side larger than the other, the larger opening facing the gas flow direction. The straight section near its connection to the curved section has multiple sound-absorbing dampers. Each damper includes a sound-absorbing block and a spring, with the spring connected to the upper and lower surfaces of the sound-absorbing block, suspending it within the duct of the straight section. All the dampers form a sound-absorbing damping group, where each sound-absorbing block is spatially staggered within the duct of the straight section, with equidistant distances between adjacent blocks. This invention effectively eliminates duct noise while avoiding impacting the duct's air delivery efficiency.

Description

Technical Field

[0001] This invention belongs to the field of building ventilation technology, and specifically relates to a sound-absorbing duct. Background Technology

[0002] Air ducts are hollow pipe structures that facilitate air supply and ventilation. They are suitable for building ventilation or ventilation on various ships and vessels. Common air ducts are just single-layer straight pipes, which often generate a lot of noise when undertaking air supply and ventilation tasks.

[0003] Chinese invention patent (application number: CN202011112501.0) with publication number CN112212116A discloses a flexible duct docking and installation device that uses an airbag structure to achieve noise reduction. The device includes an installation device and a noise reduction device. A drive box is fixedly connected to the top of the installation device. Rotating frames are movably connected to both sides of the installation device. The noise reduction device is movably connected to the lower side of the installation device, and a receiving frame is movably connected to the lower side of the installation device. This flexible duct docking and installation device, which uses an airbag structure to achieve noise reduction, places the flexible duct in the center of the installation device. The first and second gear teeth on the outer side of the flexible duct are meshed, driving the gear to rotate. The gear meshes with the movable gear rack, causing the movable gear rack to rotate. The movable gear rack moves forward. The movable gear rack has teeth on both sides, so the teeth on the left and right sides drive the semi-circular gear to move to the right. A fixed ring is connected to the docking ring and the flexible duct.

[0004] While the invention addresses the issue of duct noise reduction, it also reduces the airflow efficiency of the duct due to the obstruction caused by the noise reduction structure, which affects the airflow speed. Summary of the Invention

[0005] In view of this, the present invention provides a noise-reducing duct that can effectively eliminate duct noise while avoiding affecting the air delivery efficiency of the duct.

[0006] This invention is implemented as follows:

[0007] This invention provides a sound-absorbing duct, comprising a straight section and a bend section, wherein the straight section and the bend section are connected together by a flange mechanism, wherein the bend section has multiple gas flow guiding sound-absorbing plates, and adjacent gas flow guiding sound-absorbing plates form a horn-shaped structure with one side having a larger opening and the other side having a smaller opening, the side with the larger opening facing the gas flow direction; the straight section has multiple sound-absorbing damping elements near the connection with the bend section;

[0008] The noise-absorbing damping includes a noise-absorbing block and a spring. The spring is connected to the upper and lower surfaces of the noise-absorbing block and suspends the noise-absorbing block in the air duct of the straight pipe section. All the noise-absorbing dampings form a noise-absorbing damping group. Each noise-absorbing block in the noise-absorbing damping group is evenly staggered in space in the air duct of the straight pipe section, and the distance between adjacent noise-absorbing blocks is the same.

[0009] The technical effects of the silencing duct provided by this invention are as follows: by using silencing damping, the impact force of airflow on the bend section of the duct can be reduced, and the vibration of the bend section caused by airflow hitting the bend section can be reduced, thereby reducing the noise generated by the duct; by using a gas flow guiding silencing plate, the airflow is noise-reduced by utilizing the principle of resistance silencing.

[0010] Based on the above technical solution, the silencing duct of the present invention can be further improved as follows:

[0011] The method for locating the noise-absorbing dampers in the straight pipe section is as follows:

[0012] S1: Establish a model for silencing block arrangement;

[0013] S2: Collect training data on the arrangement of silencers;

[0014] S3: Train the muffler block arrangement model using the muffler block arrangement training data;

[0015] S4: Using the aforementioned muffler block arrangement model, output the optimal arrangement of the muffler blocks;

[0016] The specific steps of S2 include:

[0017] Step 1: Establish a spatial coordinate system for the straight pipe section;

[0018] Step 2: Establish the three-dimensional coordinates of each noise-absorbing block in the noise-absorbing damping group based on the spatial coordinate system of the straight pipe section. The noise-absorbing blocks are all the same size.

[0019] Step 3: Obtain the position vector of each noise-absorbing block based on its three-dimensional coordinates;

[0020] Step 4: Experimentally obtain the air volume and noise level of the duct under the specified arrangement of silencers for this volume.

[0021] Step 5: Change the volume of the silencer block and repeat step 4 to obtain the air volume and noise level of the duct after changing the volume of the silencer block.

[0022] Step 6: Change the three-dimensional coordinates of the silencer block, for example, increase or decrease the distance between the front and rear silencer blocks, increase or decrease the vertical distance between the upper and lower silencer blocks, to obtain the position vector of the silencer block after the position is changed. Repeat step 4 to obtain the air volume of the duct and the noise decibel of the duct corresponding to the silencer block after the position is changed.

[0023] Furthermore, the specific method for S3, "training the muffler block arrangement model using the muffler block arrangement training data," is as follows:

[0024] The volume of the silencing block and the position vector of the silencing block are used as input data for the silencing block arrangement model, and the air volume of the corresponding air duct and the noise decibel of the air duct are used as training output data to train the silencing block arrangement model.

[0025] Furthermore, the "optimal arrangement of the silencers" in S4 refers to the arrangement in which the air volume of the duct is maximized and the noise level of the duct is minimized. The arrangement includes the three-dimensional coordinates of the silencers and the volume of the silencers.

[0026] The noise-absorbing block can be one of the following shapes: a regular square prism, a polygonal prism, or a sphere.

[0027] Furthermore, preferably, the noise-absorbing block is a sphere.

[0028] The gas flow silencing plate is made of rock wool, polyester fiber, or sound-absorbing glass wool.

[0029] The sound-absorbing block has a conical through hole, into which a matching conical high acoustic impedance material insert is embedded. The side of the through hole with a larger area is opposite to the flow direction of the gas in the duct.

[0030] The mute block arrangement model is a convolutional neural network, which includes one input layer, one backbone layer, one Flatten layer, one fully connected layer, and one output layer.

[0031] The gas flow silencing plate is wavy.

[0032] Compared with the prior art, the beneficial effects of the silencing duct provided by the present invention are: by using silencing damping, the impact force of airflow on the bend section of the duct can be reduced, and the vibration of the bend section caused by airflow hitting the bend section can be reduced, thereby reducing the noise generated by the duct; by using a gas flow guiding silencing plate, the airflow is noise-reduced by utilizing the principle of resistance silencing. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 A schematic diagram of a sound-absorbing duct provided by the present invention;

[0035] Figure 2 This invention provides a flowchart of a method for locating the arrangement of silencer blocks in a straight pipe section within a silencer duct;

[0036] Figure 3 This invention provides a schematic diagram of a damping block in a sound-absorbing duct;

[0037] Figure 4 This invention provides a schematic diagram of a damping block embedded in a sound-absorbing duct.

[0038] The attached diagram lists the components represented by each number as follows:

[0039] 1. Gas flow guide silencer; 3. Silencing damper; 31. Silencing block; 32. Spring. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0042] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0043] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0044] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0045] like Figure 1 The image shows a first embodiment of a sound-absorbing duct provided by the present invention. In this embodiment, it includes a straight pipe section and a bend pipe section. The straight pipe section and the bend pipe section are connected together by a flange mechanism. The bend pipe section has multiple gas flow sound-absorbing plates 1 inside. Adjacent gas flow sound-absorbing plates 1 form a horn-shaped structure with one side having a larger opening and the other side having a smaller opening. The side with the larger opening faces the gas flow direction. The straight pipe section has multiple sound-absorbing damping devices 3 near the connection with the bend pipe section.

[0046] The noise-absorbing damper 3 includes a noise-absorbing block 31 and a spring 32. The spring 32 is connected to the upper and lower surfaces of the noise-absorbing block 31. The spring 32 suspends the noise-absorbing block 31 in the air duct of the straight pipe section. All the noise-absorbing dampers 3 form a noise-absorbing damping group. In the noise-absorbing damping group, each noise-absorbing block 31 is evenly staggered in space in the air duct of the straight pipe section, and the distance between adjacent noise-absorbing blocks 31 is the same.

[0047] Reactive silencing is achieved by reducing the sound energy radiated outward from the silencer by reflecting or interfering with the sound energy caused by changes in impedance at abrupt changes in the cross-section of the pipeline or by a resonant cavity.

[0048] like Figure 2 As shown, in the above technical solution, the method for locating the noise-absorbing damper 3 in the straight pipe section is as follows:

[0049] S1: Establish a model for silencing block arrangement;

[0050] S2: Collect training data on the arrangement of silencers;

[0051] S3: Train the mute block arrangement model using mute block arrangement training data;

[0052] S4: Using the muffler block arrangement model, output the optimal arrangement of the muffler blocks;

[0053] The specific steps of S2 include:

[0054] Step 1: Establish a spatial coordinate system for the straight pipe section;

[0055] Step 2: Establish the three-dimensional coordinates of each noise-absorbing block 31 in the noise-absorbing damping group based on the spatial coordinate system of the straight pipe section. All noise-absorbing blocks 31 have the same volume.

[0056] Step 3: Based on the three-dimensional coordinates of each noise-absorbing block 31, obtain the position vector of each noise-absorbing block 31;

[0057] Step 4: The experiment was conducted to obtain the air volume and noise level of the duct under the arrangement of the 31 silencers of this volume.

[0058] Step 5: Change the volume of the silencer block 31, repeat step 4, and obtain the air volume and noise level of the duct after changing the volume of the silencer block 31.

[0059] Step 6: Change the three-dimensional coordinates of the silencer block 31, for example, increase or decrease the distance between the front and rear silencer blocks 31, increase or decrease the vertical distance between the upper and lower silencer blocks 31, to obtain the position vector of the silencer block 31 after the position is changed. Repeat step 4 to obtain the air volume of the duct and the noise decibel of the duct corresponding to the silencer block 31 after the position is changed.

[0060] The method for measuring the airflow of a duct can utilize Chinese invention patent CN113587410B (application number: CN202110789147.3), which discloses an airflow measuring device, a subway air conditioning system, and a control method. The airflow measuring device includes: a static pressure chamber with a first opening, a second opening, and a third opening. The static pressure chamber is connected to the return air chamber of the subway air conditioning system through the first opening and to the exhaust duct of the subway air conditioning system through the second opening; a pressure stabilizing pipe, including a first pipe section and a second pipe section connected to each other, with the first and second pipe sections having the same diameter. The static pressure chamber is connected to the first pipe section through the third opening, and the second pipe section is connected to the exhaust duct; and an orifice plate differential pressure flow meter is disposed between the first and second pipe sections. When the small fresh air mode of the subway air conditioning system is activated, the first and third openings are open, and the second opening is closed. The orifice plate differential pressure flow meter is used to measure the pressure difference to measure the exhaust airflow of the exhaust duct. This embodiment of the invention can achieve relatively accurate measurement of fresh air volume.

[0061] A method for measuring duct noise can be found in Chinese invention patent CN113548134B (application number: CN202110721058.5), which discloses a system and method for calculating air conditioning ventilation noise. The method includes: measuring the total airflow value Qi and the corresponding ventilation noise sound pressure level Li under multiple settings and levels in various modes; calculating the slope and constant of the functional relationship between the total airflow value Qi and the ventilation noise sound pressure level at each frequency fj when the airflow is Qi using linear fitting; and superimposing the noise values ​​at each frequency to obtain the total sound pressure level Li at the human ear. This method allows for the rapid calculation of noise at the human ear under any airflow level, and also allows for the calculation of the total airflow by measuring the noise value at the human ear.

[0062] The decibel (dB) is a unit of measurement in electrical and acoustic systems. It represents the ratio of two electrical or acoustic powers, or two voltage or current values, or similar sound quantities; the decibel is also a unit for measuring the relative loudness of sound. The decibel is expressed in dB.

[0063] The decibel represents a unit that is the ratio of two electrical or acoustic powers, or two voltage or current values, or similar sound quantities; the decibel is also a unit for measuring the relative loudness of a sound.

[0064] Furthermore, in the above technical solution, the specific method for S3 "training the muffler block arrangement model using muffler block arrangement training data" is as follows:

[0065] The volume of the silencing block 31 and the position vector of the silencing block 31 are used as input data for the silencing block arrangement model, and the air volume of the corresponding duct and the noise decibel of the duct are used as training output data to train the silencing block arrangement model.

[0066] Furthermore, in the above technical solution, the "optimal arrangement of the silencers" in S4 is the arrangement in which the air volume of the duct is maximized and the noise level of the duct is minimized. The arrangement includes the three-dimensional coordinates of the silencers 31 and the volume of the silencers 31.

[0067] In the above technical solution, the noise-absorbing block 31 can be one of the following shapes: a regular square prism, a polygonal prism, or a sphere.

[0068] Furthermore, in the above technical solution, preferably, the silencing block 31 is a sphere.

[0069] Since a sphere can be considered approximately streamlined, and streamline is an external shape of an object, it is usually characterized by a smooth and regular surface without large undulations or sharp edges. Fluids on the surface of streamlined objects mainly exhibit laminar flow with little or no turbulence, thus preventing the noise-absorbing block 31 from being violently shaken by the airflow.

[0070] In the above technical solution, the gas flow silencing plate 1 is made of rock wool silencing plate, polyester fiber silencing plate, or silencing glass wool plate.

[0071] Rock wool board, also known as rock wool insulation and decorative board, is an inorganic fiber board made from basalt as the main raw material and processed by high-temperature melting. It was successfully tested in June 1981 and is a new type of thermal insulation, fireproof and sound-absorbing material.

[0072] Glass wool is a roll-type product made by melting glass, fiberizing it, and then curing it with the addition of binders. The diameter of the glass wool fibers depends on the centrifugal extrusion technology. The difference lies in the centrifugal technology, and the most widely used centrifugal technology is Saint-Gobain's TEL centrifugal technology, which is the originator of glass wool products.

[0073] The gas flow silencing plate 1 has a supporting frame to prevent it from being deformed by the airflow.

[0074] In the above technical solution, the silencing block 31 has a conical through hole, in which a matching conical high acoustic impedance material insert is embedded, and the side with the larger area of ​​the through hole is opposite to the flow direction of the gas in the duct.

[0075] like Figure 3-4 As shown, the acoustic impedance of the silencing block 31 is the product of the density and the speed of sound.

[0076] If the sound-absorbing block 31 is divided into countless sections parallel to the horizontal direction, then the countless sections are stacked along the thickness direction to form the sound-absorbing layer material.

[0077] The density and sound velocity of each section are determined by the ratio of the low acoustic impedance polymer matrix to the high acoustic impedance block, because both the shape of the through-hole and the shape of the high acoustic impedance block adopt a conical structure.

[0078] Therefore, from the perspective of thickness, the ratio of low acoustic impedance polymer matrix to high acoustic impedance block changes continuously in countless cross-sections from the bottom to the top.

[0079] Therefore, the acoustic impedance of the cross section also changes continuously, and the acoustic impedance changes continuously along the thickness direction of the acoustic impedance layer.

[0080] Since the acoustic impedance is determined by the density and sound velocity of the materials of the insert and the matrix of the sound-absorbing block 31, the ratio of the polymer matrix and the high acoustic impedance insert on the two end faces in the thickness direction can be calculated based on the acoustic impedance of the selected high acoustic impedance insert and matrix material to achieve precise control of the acoustic impedance gradient of the material.

[0081] The acoustic impedance of the silencing block 31 with this structure can be easily and precisely controlled.

[0082] In the above technical solution, the mute block arrangement model is a convolutional neural network, including one input layer, one backbone layer, one Flatten layer, one fully connected layer, and one output layer.

[0083] Convolutional Neural Networks (CNNs) are a class of feedforward neural networks that incorporate convolutional computations and have a deep structure. They are one of the representative algorithms of deep learning. CNNs possess representation learning capabilities, enabling them to perform shift-invariant classification of input information according to their hierarchical structure; therefore, they are also known as Shift-Invariant Artificial Neural Networks (SIANNs).

[0084] In the above technical solution, the gas flow silencing plate 1 is wavy.

[0085] Specifically, the principle of this invention is as follows: when the airflow flows from the straight pipe section through the curved pipe section, the force of the airflow is first consumed by the noise damping 3. When the airflow hits the pipe wall of the curved pipe section, the impact force of the airflow will not cause the pipe wall of the curved pipe section to vibrate and generate noise. When the airflow passes between the gas guide noise damping plates 1, the diameter of the gas guide noise damping plates 1 suddenly increases, and the noise of the airflow is reduced by using resistance noise reduction.

[0086] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for locating the sound-absorbing damping arrangement position of a sound-absorbing duct, wherein, A sound-absorbing duct includes a straight section and a bend section, the straight section and the bend section being connected together by a flange mechanism. The bend section contains multiple gas-guiding sound-absorbing plates (1), and adjacent gas-guiding sound-absorbing plates (1) form a horn-shaped structure with one side having a larger opening and the other side having a smaller opening, allowing gas to flow from the side with the smaller opening to the side with the larger opening. The straight section has multiple sound-absorbing damping devices (3) near its connection to the bend section. The noise-absorbing damper (3) includes a noise-absorbing block (31) and a spring (32). The spring (32) is connected to the upper and lower surfaces of the noise-absorbing block (31). The spring (32) suspends the noise-absorbing block (31) in the air duct of the straight pipe section. All the noise-absorbing dampers (3) form a noise-absorbing damping group. Each noise-absorbing block (31) in the noise-absorbing damping group is evenly staggered in space in the air duct of the straight pipe section, and the distance between adjacent noise-absorbing blocks (31) is the same. The method for locating the noise-absorbing damper (3) in the straight pipe section is as follows: S1: Establish a model for silencing block arrangement; S2: Collect training data on the arrangement of silencers; S3: Train the muffler block arrangement model using the muffler block arrangement training data; S4: Using the aforementioned muffler block arrangement model, output the optimal arrangement of the muffler blocks; The specific steps of S2 include: Step 1: Establish a spatial coordinate system for the straight pipe section; Step 2: Establish the three-dimensional coordinates of each of the noise-absorbing blocks (31) in the noise-absorbing damping group based on the spatial coordinate system of the straight pipe section. The noise-absorbing blocks (31) are all the same size. Step 3: Based on the three-dimensional coordinates of each of the noise-absorbing blocks (31), obtain the position vector of each of the noise-absorbing blocks (31); Step 4: The experiment was conducted to obtain the air volume and noise level of the duct under the arrangement of the silencers (31) at this volume. Step 5: Change the volume of the silencer block (31), repeat step 4, and obtain the air volume and noise decibel of the duct corresponding to the change of the volume of the silencer block (31); Step 6: Change the three-dimensional coordinates of the silencing block (31). By increasing or decreasing the distance between the front and rear silencing blocks (31) and increasing or decreasing the vertical distance between the upper and lower silencing blocks (31), obtain the position vector of the silencing block (31) after the position is changed. Repeat Step 4 to obtain the air volume of the duct and the noise decibel of the duct corresponding to the silencing block (31) after the position is changed. The specific method for S3, "training the muffler block arrangement model using the muffler block arrangement training data," is as follows: The volume of the silencing block (31) and the position vector of the silencing block (31) are used as input data for the silencing block arrangement model, and the air volume of the corresponding air duct and the noise decibel of the air duct are used as training output data to train the silencing block arrangement model.

2. The method for locating the sound-absorbing damping arrangement of a sound-absorbing duct according to claim 1, characterized in that, The "optimal arrangement of the silencers" in S4 refers to the arrangement in which the air volume of the duct is maximized and the noise level of the duct is minimized. The arrangement includes the three-dimensional coordinates of the silencers (31) and the volume of the silencers (31).

3. The method for locating the sound-absorbing damping arrangement position of a sound-absorbing duct according to claim 1, characterized in that, The noise-absorbing block (31) is one of the following shapes: a regular square prism, a polygonal prism, or a sphere.

4. The method for locating the sound-absorbing damping arrangement position of a sound-absorbing duct according to claim 3, characterized in that, The noise-absorbing block (31) is a sphere.

5. The method for locating the sound-absorbing damping arrangement of a sound-absorbing duct according to claim 1, characterized in that, The gas flow silencing plate (1) is made of rock wool, polyester fiber, or sound-absorbing glass wool.

6. The method for locating the sound-absorbing damping arrangement position of a sound-absorbing duct according to claim 1, characterized in that, The silencing block (31) has a conical through hole, in which a matching conical high acoustic impedance material insert is embedded, and the larger side of the through hole is opposite to the flow direction of the gas in the duct.

7. The method for locating the sound-absorbing damping arrangement position of a sound-absorbing duct according to claim 1, characterized in that, The mute block arrangement model is a convolutional neural network, including one input layer, one backbone layer, one Flatten layer, one fully connected layer, and one output layer.

8. The method for locating the sound-absorbing damping arrangement position of a sound-absorbing duct according to claim 1, characterized in that, The gas flow silencing plate (1) is wavy.

Images