WO2023028813A1 - 一种低通声滤波器组宽频吸声体 - Google Patents

一种低通声滤波器组宽频吸声体 Download PDF

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Publication number
WO2023028813A1
WO2023028813A1 PCT/CN2021/115552 CN2021115552W WO2023028813A1 WO 2023028813 A1 WO2023028813 A1 WO 2023028813A1 CN 2021115552 W CN2021115552 W CN 2021115552W WO 2023028813 A1 WO2023028813 A1 WO 2023028813A1
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low
cavity
sound wave
channel
main channel
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PCT/CN2021/115552
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English (en)
French (fr)
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梅玉林
王晓明
王元秀
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大连理工大学
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Priority to US17/792,026 priority Critical patent/US20230215411A1/en
Priority to EP21912326.2A priority patent/EP4174843A4/en
Priority to PCT/CN2021/115552 priority patent/WO2023028813A1/zh
Publication of WO2023028813A1 publication Critical patent/WO2023028813A1/zh

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    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62—Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84—Sound-absorbing elements
    • E04B1/86—Sound-absorbing elements slab-shaped
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/162—Selection of materials
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/20—Reflecting arrangements
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62—Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84—Sound-absorbing elements
    • E04B2001/8457—Solid slabs or blocks
    • E04B2001/8476—Solid slabs or blocks with acoustical cavities, with or without acoustical filling
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/02—Mechanical acoustic impedances; Impedance matching, e.g. by horns; Acoustic resonators
    • G10K11/04—Acoustic filters ; Acoustic resonators

Definitions

  • the invention belongs to the technical field of vibration reduction and noise reduction, and relates to a low-pass sound filter group broadband sound absorbing body.
  • a low-pass acoustic filter group broadband sound absorber comprising a micro-perforated plate, a cavity behind the micro-perforated plate, a meandering sound wave main channel communicated with the plate back cavity, and a low-pass sound wave arranged along the meandering sound wave main channel acoustic filter bank;
  • the micro-perforated plate has a plate thickness not greater than 2mm, a perforated diameter not greater than 0.5mm, and a perforation rate not greater than 5%; one side of the micro-perforated plate is the external sound wave incident end, and a cavity is arranged behind the other side.
  • the cavity is surrounded by side walls, and the volume of the cavity is estimated by multiplying the area of the micro-perforated plate by the numerical result of the perforation rate.
  • the end of the cavity communicates with the beginning of the main sound channel; Then enter the main acoustic channel from the cavity;
  • the main meandering sound wave channel is a circuitous, curved, coiled or helical channel; the main sound wave channel is either a channel with variable cross-section or a channel with equal cross-section.
  • the pattern of layers or layers is closely arranged; the beginning of the sound wave main channel communicates with the end of the cavity behind the micro-perforated plate, and the end of the sound wave main channel is closed; The channels between them are connected to ensure that the sound wave main channel is connected from the beginning to the end; in the single-layer or multi-layer meandering sound wave main channel, according to the design requirements, sound-absorbing materials are arranged or not arranged;
  • Described low-pass acoustic filter bank is made up of a plurality of low-pass acoustic filters with different cut-off frequencies, and acoustic filter is arranged along the main channel of the sound wave of zigzag according to the order of cut-off frequency from high to low;
  • the low-pass acoustic filters N1, N2...Ni...Nn are arranged in sequence along the main sound channel, and the cut-off frequency of these low-pass acoustic filters satisfies f1>f2>...>fi>...>fn; the first low-pass The cut-off frequency f1 of the acoustic filter N1 is the highest, arranged near the beginning of the sound wave main channel; the cut-off frequency fn of the last low-pass acoustic filter Nn is the lowest, arranged near the end of the sound wave main channel;
  • Each of the low-pass acoustic filters arranged along the meandering sound wave main channel is composed of one or more cavities and a section of sound wave main channel communicating with the cavity; each cavity is surrounded by a plurality of free-form surfaces, Either surrounded by multiple planes, or jointly surrounded by multiple curved surfaces and planes, the cavity is either arranged with sound-absorbing materials or not arranged; when the low-pass acoustic filter only includes a single cavity, the single cavity or the sound wave The main channel is directly connected, or a thin branch tube is arranged between the single cavity and the main sound wave channel, so that the single cavity communicates with the main sound wave channel through the thin branch tube; when the low-pass acoustic filter includes multiple cavities, the definition is the same as that of the main sound wave channel The cavity adjacent to the channel is the interface cavity.
  • the interface cavity is either directly communicated with the main acoustic channel, or a thin branch tube is arranged between the interface cavity and the main acoustic channel to communicate with the main acoustic channel.
  • the function of the interface cavity is to guide The sound waves from the meandering main channel are passed into the low-pass acoustic filter, or the sound waves in the low-pass acoustic filter are guided out of the acoustic filter into the meandering main channel; when the low-pass acoustic filter includes multiple cavities, the multiple cavities
  • the cavities are communicated through one or more thin branch tubes to ensure that all the cavities of the low-pass acoustic filter are communicated with the main channel of the sound wave; Shunt, part of it enters the cavity of the low-pass acoustic filter or is absorbed or reflected, and part of it continues to propagate along the main channel of the sound wave;
  • the low-pass acoustic filter group arranged along the meandering sound wave main channel defines the equivalent sum of all cavity volumes of each low-pass acoustic filter as the volume of the low-pass acoustic filter, and represents the low-pass acoustic filter with Vi
  • the low-pass acoustic filter bank composed of acoustic filters, at the arranged n low-pass acoustic filters, realizes the expansion of the sound wave propagation space to the cavity of
  • thin branch tubes can be arranged between one or more cavities of the filter and the main acoustic channel according to the design requirements, while retaining the cavity of the filter and the main acoustic channel. On the basis of the path, add additional paths;
  • the thin branch tube that communicates between the cavity of the low-pass acoustic filter and the main acoustic channel, or extends to the interior of the cavity and the main acoustic channel, or does not extend; between multiple cavities of the low-pass acoustic filter
  • the thin branch tube that plays a communicating role either extends to the inside of the cavity or does not extend; for a low-pass acoustic filter that only contains a single cavity, when its cavity directly communicates with the main acoustic channel, the main acoustic wave that communicates with the cavity
  • the channel either extends to the inside of the cavity or does not extend; for a low-pass acoustic filter comprising multiple cavities, when the interface cavity of the acoustic filter is directly communicated with the main acoustic channel, the main acoustic channel communicated with the interface cavity or extend to the interior of the cavity, or not extend;
  • the most important feature of the low-pass acoustic filter bank broadband sound absorber is that it adopts a main sound wave channel to meet the phase propagation delay requirements of a micro-perforated plate for absorbing sound waves in different center frequency bands, and realize ultra-broadband sound absorption from low frequency to high frequency. Acoustic, combined with the meandering arrangement of the main channel of the sound wave, to achieve ultra-thin structural size.
  • Figure 1 is a schematic diagram of a low-pass acoustic filter bank broadband sound absorber.
  • Fig. 2 is a schematic diagram of a low-pass acoustic filter bank broadband sound absorbing body.
  • Fig. 3 is a schematic diagram of a low-pass acoustic filter bank broadband sound absorbing body.
  • Fig. 4 is a schematic diagram of an "L" shaped sound wave main channel.
  • Fig. 5 is a schematic diagram of a "U" shaped acoustic wave main channel.
  • Fig. 6 is a schematic diagram of a spiral sound wave main channel.
  • Fig. 7 is a schematic diagram of the main channel of the serpentine sound wave.
  • Fig. 8 is a schematic diagram of a three-layer acoustic wave main channel.
  • Fig. 9 is a low-pass acoustic filter composed of a single cavity and a section of variable-section acoustic wave main channel.
  • Figure 10 is a low-pass acoustic filter composed of a single cavity, a thin branch tube and a section of equal-section acoustic wave main channel.
  • Figure 11 is a low-pass acoustic filter composed of a single cavity and a section of variable-section acoustic wave main channel.
  • Fig. 12 is a low-pass acoustic filter composed of a single cavity, a thin branch pipe and a section of variable-section acoustic wave main channel.
  • Figure 13 is a low-pass acoustic filter composed of a single cavity and a section of equal-section acoustic wave main channel.
  • Figure 14 is a low-pass acoustic filter composed of a single cavity and a section of equal-section acoustic wave main channel.
  • Fig. 15 is a low-pass acoustic filter composed of double chambers, thin branch pipes and a section of variable-section acoustic wave main channel.
  • Fig. 16 is a low-pass acoustic filter composed of double chambers, thin branch pipes and a section of equal-section acoustic wave main channel.
  • Fig. 17 is the low-pass acoustic filter that is made of double cavity, thin branch pipe and a section of variable section acoustic wave main channel.
  • Fig. 18 is a low-pass acoustic filter composed of double chambers, thin branch pipes and a section of variable-section acoustic wave main channel.
  • Fig. 19 is a low-pass acoustic filter composed of double cavities, thin branch pipes and a section of equal-section acoustic wave main channel.
  • Fig. 20 is: a low-pass acoustic filter composed of double chambers, thin branch pipes and a section of equal-section acoustic wave main channel.
  • Fig. 21 is a low-pass acoustic filter composed of double chambers, thin branch pipes and a section of variable-section acoustic wave main channel.
  • Fig. 22 is a low-pass acoustic filter composed of double chambers, thin branch pipes and a section of variable-section acoustic wave main channel.
  • Fig. 23 is the low-pass acoustic filter that is made of double cavity, thin branch pipe and a section of variable section sound wave main channel.
  • Figure 24 is a low-pass acoustic filter composed of three cavities, thin branch pipes and a section of variable-section acoustic wave main channel.
  • Figure 25 is a low-pass acoustic filter composed of three cavities, thin branch pipes and a section of equal-section acoustic wave main channel.
  • Fig. 26 is a low-pass acoustic filter composed of three cavities, thin branch pipes and a section of variable-section acoustic wave main channel.
  • Figure 27 is a low-pass acoustic filter composed of five cavities, thin branch pipes and a section of variable-section acoustic wave main channel.
  • the micro-perforated plate 2. The cavity behind the micro-perforated plate; 3. The beginning of the main acoustic channel (the end of the cavity behind the micro-perforated plate); 4. The main channel of the acoustic wave; 5. The end of the main acoustic channel; 6. Along the main acoustic channel Arranged low-pass acoustic filter; 7. Thin branch tube; 8. Low-pass acoustic filter interface cavity; 9. Low-pass acoustic filter auxiliary cavity;
  • the arrow in the figure indicates the propagation direction of the sound wave.
  • Embodiment 1 as shown in Figure 1
  • the low-pass acoustic filter bank broadband sound absorber consists of a micro-perforated plate 1, a cavity 2 behind the micro-perforated plate, a meandering sound wave main channel 4 communicating with the plate back cavity 2, and a main meandering sound wave channel 4 arranged along the meandering sound wave main channel 4.
  • Low-pass sound filter bank composition
  • the micro-perforated plate 1 has an external sound wave incident end on one side, and a cavity 2 is arranged on the other side.
  • the cavity 2 is surrounded by side walls.
  • the volume of the cavity 2 is calculated according to the area of the micro-perforated plate 1 multiplied by its perforation Estimated by the numerical results of the rate, the end of the cavity 2 is connected to the beginning 3 of the main acoustic channel; the external incident sound wave enters the subsequent cavity 2 through the micro-perforated plate 1, and then enters the main acoustic channel 4 from the cavity 2;
  • the meandering sound wave main channel 4 is an approximately U-shaped variable cross-section single-layer channel, and porous sound-absorbing materials are arranged locally in the channel, and the end 5 of the sound wave main channel is closed;
  • the low-pass sound filter bank is arranged along the sound wave main channel 4; the low-pass sound filter bank is made up of 6 low-pass sound filters 11, 12, 13, 14, 15 and 16; Acoustic filters 12 and 13 are respectively composed of a single cavity and a section of equal-section sound wave main channel communicating with the cavity, and the single cavity is directly connected with the sound wave main channel; low-pass acoustic filters 11, 14, 15 and 16 are composed of A single cavity and a section of variable-section sound wave main channel communicated with the cavity are formed, and the single cavity is directly communicated with the sound wave main channel; the cutoff frequencies of the low-pass acoustic filters 11, 12, 13, 14, 15 and 16 are respectively f1, f2, f3, f4, f5 and f6 satisfy f1>f2>f3>f4>f5>f6; use V1, V2, V3, V4, V5 and V6 to represent low-pass acoustic filters 11, 12, 13, 14, The equivalent volumes of 15 and 16 satisfy V1 ⁇ V
  • the sound waves from the meandering main channel 4 are shunted when passing through the low-pass acoustic filters 11, 12, 13, 14, 15 and 16 communicating with the main channel 4, and a part enters the cavity of the low-pass acoustic filter or is absorbed or Reflected, a part continues to propagate along the main acoustic channel 4, as shown by the arrow in Figure 1;
  • 6 low-pass acoustic filters communicated with the main channel are arranged along the meandering sound wave main channel 4, and at the low-pass acoustic filters 11, 12, 13, 14, 15 and 16 of the arrangement, the propagation space of the sound wave is realized toward the main channel. 4, and the expansion space becomes larger with the increase of the depth of the main channel 4, and then at the six low-pass acoustic filters 11, 12, 13, 14, 15 and 16, the reflection of high-frequency to low-frequency sound waves is realized in sequence.
  • Embodiment 2 as shown in Figure 2
  • Embodiment 2 is basically the same as Embodiment 1, the main difference is:
  • the low-pass acoustic filter 13 is composed of a single cavity and a section of variable-section acoustic wave main channel communicated with the cavity;
  • the low-pass acoustic filter 14 is composed of a single cavity and a section of variable-section sound wave main channel communicated with the cavity, and the variable-section sound wave main channel extends to the inside of the cavity;
  • the low-pass acoustic filter 15 is composed of an interface cavity 8, an auxiliary cavity 9, a thin branch tube 7 communicating with the double cavities 8 and 9, and a section of equal-section sound wave main channel communicated with the interface cavity 8, and the thin branch tube 7 extends into the cavity;
  • the low-pass acoustic filter 16 is composed of an interface cavity 8, an auxiliary cavity 9, a thin branch tube 7 communicating with the double cavities 8 and 9, and a section of variable-section sound wave main passage communicated with the interface cavity 8.
  • the thin branch tube 7 is not extend;
  • a porous sound-absorbing material is arranged in the double chambers 8 and 9 of the low-pass acoustic filter 16 .
  • Embodiment 3 as shown in Figure 3
  • the low-pass acoustic filter bank broadband sound absorber consists of a micro-perforated plate 1, a cavity 2 behind the micro-perforated plate, a meandering sound wave main channel 4 communicating with the plate back cavity 2, and a main meandering sound wave channel 4 arranged along the meandering sound wave main channel 4.
  • Low-pass sound filter bank composition
  • the micro-perforated plate 1 has an external sound wave incident end on one side, and a cavity 2 is arranged on the other side.
  • the cavity 2 is surrounded by side walls.
  • the volume of the cavity 2 is calculated according to the area of the micro-perforated plate 1 multiplied by its perforation Estimated by the numerical results of the rate, the end of the cavity 2 is connected to the beginning 3 of the main acoustic channel; the external incident sound wave enters the subsequent cavity 2 through the micro-perforated plate 1, and then enters the main acoustic channel 4 from the cavity 2;
  • the meandering sound wave main channel 4 is a meandering single-layer channel with equal cross-section, and the end 5 of the main sound wave channel is closed;
  • the low-pass sound filter bank is arranged along the sound wave main channel 4;
  • the low-pass sound filter bank is made up of 5 low-pass sound filters 11, 12, 13, 14 and 15;
  • the low-pass sound filter Devices 11 and 12 are respectively composed of an annular single cavity and a section of equal-section sound wave main channel communicating with the cavity, and the cavity is directly connected with the sound wave main channel 4;
  • low-pass acoustic filters 13 and 14 are respectively composed of an interface cavity cavity 8, an auxiliary cavity 9, a thin branch tube 7 communicating with the double cavities, and a section of equal-section sound wave main channel communicating with the interface cavity 8.
  • the interface cavities 8 of the low-pass acoustic filters 13 and 14 are respectively connected to the The sound wave main channel 4 is directly connected; the low-pass acoustic filter 15 consists of an interface cavity 8, two auxiliary cavities 9, two thin branch tubes 7 connecting the three cavities, and a section communicating with the interface cavity 8, etc.
  • the cross-section sound wave main channel is formed, the interface cavity 8 of the low-pass acoustic filter 15 communicates with the sound wave main channel 4 through a thin branch tube, the thin branch tube connecting the cavity 8 and the sound wave main channel 4 does not extend, and the thin branch tube connecting the cavity 8 and 9
  • the branch pipe does not extend, and the thin branch pipe 7 connecting the two auxiliary cavities 9 extends to the inside of the cavity;
  • the cut-off frequencies of the five low-pass acoustic filters 11, 12, 13, 14 and 15 are respectively f1, f2, f3, f4 and f5, satisfy f1>f2>f3>f4>f5;
  • use V1, V2, V3, V4 and V5 to represent the equivalent volumes of low-pass acoustic filters 11, 12, 13, 14 and 15 respectively, and they satisfy V1 ⁇ V2 ⁇ V3 ⁇ V4 ⁇ V5;
  • the first low-pass acoustic filter 11 is arranged near the beginning 3 of the sound wave main channel, its cut-off frequency f
  • the sound waves from the meandering main channel 4 are shunted when passing through the low-pass acoustic filters 11, 12, 13, 14 and 15 communicating with the main channel 4, and a part enters the cavity of the low-pass acoustic filter or is absorbed or reflected, A part continues to propagate along the main acoustic channel 4, as shown by the arrow in the figure;
  • 5 low-pass acoustic filters communicated with the main channel are arranged along the meandering sound wave main channel 4, and at the arranged low-pass acoustic filters 11, 12, 13, 14 and 15, the propagation space of the sound wave is realized outside the main channel 4 expansion, and the expansion space becomes larger with the increase of the depth of the main channel 4, and then at the five low-pass acoustic filters 11, 12, 13, 14 and 15, the reflection of high-frequency to low-frequency sound waves is realized in sequence.
  • Porous sound-absorbing materials are arranged near the low-pass sound filter in the channel.
  • Embodiment 4 is basically the same as Embodiment 1, the main difference is:
  • the meandering sound wave main channel 4 adopts the type shown in Fig. 4 , Fig. 5 , Fig. 6 or Fig. 7 .
  • Embodiment 5 is basically the same as Embodiment 3, the main difference is:
  • the meandering sound wave main channel 4 adopts a spiral arrangement of three layers superimposed, as shown in Figure 8, channel communication holes 20 are arranged between adjacent layers to ensure that the sound wave main channel is connected from the beginning 3 to the end 5, and the meandering sound wave main channel 4 is a variable cross-section channel;
  • Single-cavity low-pass acoustic filters 11 and 12 adopt the type of Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13 or Fig. 14;
  • Double-cavity low-pass acoustic filter 13 and 14 adopt the type of Fig. 15, Fig. 16, Fig. 17, Fig. 18, Fig. 19, Fig. 20, Fig. 21, Fig. 22 or Fig. 23;
  • the three-cavity low-pass acoustic filter 15 is in the form of Fig. 24, Fig. 25 or Fig. 26.
  • Embodiment 6 is a diagrammatic representation of Embodiment 6
  • Embodiment 6 is basically the same as Embodiment 3, the main difference is:
  • the meandering sound wave main channel 4 is a variable section channel
  • FIG. 27 Replace the three-cavity low-pass filter 15 with a five-cavity low-pass filter, and the five-cavity low-pass filter is shown in Figure 27. It consists of 2 interface cavities 8, 3 auxiliary cavities 9, and a connecting cavity The thin branch tube 7 and a section of variable section acoustic wave main channel communicated with the interface cavity 8 are formed.

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Abstract

一种低通声滤波器组宽频吸声体，包括一张微穿孔板、微穿孔板后空腔、与板后空腔相通的一条等截面或变截面曲折声波主通道，以及从声波主通道入口开始沿声波主通道按照截止频率从高到低的顺序布置的多个低通声滤波器。微穿孔板一侧为外部声波入射端，另一侧后布置有空腔，空腔末端与声波主通道的始端相通；外部入射的声波通过微穿孔板进入其后的空腔，而后由空腔进入声波主通道；曲折声波主通道是一条末端封闭的、迂回弯曲的通道，以单层或多层的型式在吸声体中紧密布置；当声波主通道以多层型式布置时，相邻层之间的通道相通，以保证声波主通道从始端到末端连通。该低通声滤波器组宽频吸声体，既能实现采用一条声波主通道，满足一张微穿孔板对吸收不同中心频带声波的相位传播延迟的要求，同时结合声波主通道曲折布置，也能实现超薄的结构尺寸。

Description

一种低通声滤波器组宽频吸声体 技术领域
本发明属于减振降噪技术领域，涉及到一种低通声滤波器组宽频吸声体。
背景技术
目前吸声结构普遍存在的问题是：在严格限制结构尺寸的条件下，中高频吸声效果好，但低频吸声效果差，若将低频吸声截止频率下限拓展至100Hz以下，且兼顾宽频吸声性能，设计将十分困难。
发明内容
本发明采用的技术方案如下：
一种低通声滤波器组宽频吸声体，包括一张微穿孔板、微穿孔板后空腔、与板后空腔相通的一条曲折声波主通道，以及沿曲折声波主通道布置的低通声滤波器组；
所述的一张微穿孔板，板厚不大于2mm，穿孔直径不大于0.5mm，穿孔率不大于5％；微穿孔板一侧为外部声波入射端，另一侧后布置有空腔，空腔由侧壁围成，空腔容积根据微穿孔板面积乘以穿孔率的数值结果估算，空腔末端与声波主通道的始端相通；外部入射的声波通过微穿孔板进入其后的空腔，而后由空腔进入声波主通道；
所述的一条曲折声波主通道，为迂回、弯曲、盘绕或螺旋形的通道；声波主通道或者为变截面通道，或者为等截面通道，在低通声滤波器组宽频吸声体中以单层或多层的型式紧密布置；声波主通道始端与微穿孔板后空腔的末端相通，声波主通道末端封闭；当曲折声波主通道在吸声体中以多层型式布置时，相邻层之间的通道相通，以保证声波主通道从始端到末端连通；在单层或多层的曲折声波主通道中，根据设计需求，或布置吸声材料或不布置；
所述的低通声滤波器组由多个具有不同截止频率的低通声滤波器组成，声 滤波器按照截止频率从高到低的顺序沿曲折的声波主通道布置；用Ni(i＝1、2……n)表示第i个低通声滤波器，用fi(i＝1、2……n)表示第i个低通声滤波器Ni的截止频率，则从声波主通道入口开始，沿声波主通道依次布置低通声滤波器N1、N2……Ni……Nn，这些低通声滤波器的截止频率满足f1>f2>……>fi>……>fn；第1个低通声滤波器N1的截止频率f1最高，布置在声波主通道始端附近；最后一个低通声滤波器Nn的截止频率fn最低，布置在声波主通道末端附近；
所述的沿曲折声波主通道布置的每个低通声滤波器，由一个或多个空腔和与空腔相通的一段声波主通道构成；每个空腔或者由多个自由曲面围成，或者由多个平面围成，或者由多个曲面和平面共同围成，空腔中或者布置吸声材料或者不布置；当低通声滤波器仅包括单空腔时，单空腔或者与声波主通道直接相通，或者在单空腔和声波主通道之间布置细支管，使单空腔通过细支管与声波主通道相通；当低通声滤波器包括多个空腔时，定义与声波主通道邻近的空腔为接口空腔，接口空腔或者与声波主通道直接相通，或者在接口空腔和声波主通道之间布置细支管使其与声波主通道相通，接口空腔的作用是引导来自曲折主通道的声波传入低通声滤波器，或引导低通声滤波器中的声波传出声滤波器进入曲折主通道；当低通声滤波器包括多个空腔时，多个空腔之间通过一个或多个细支管连通，以保证低通声滤波器的所有空腔和声波主通道连通；来自曲折主通道的声波，在经过与主通道连通的低通声滤波器时被分流，一部分进入低通声滤波器的空腔或被吸收或被反射，一部分沿声波主通道继续传播；
所述的沿曲折声波主通道布置的低通声滤波器组，定义每个低通声滤波器所有空腔容积的等效和为该低通声滤波器的容积，用Vi表示低通声滤波器Ni(i＝1、2、3……n)的容积；从声波主通道入口开始，按照截止频率从高到低 的顺序，沿曲折声波主通道布置n个低通声滤波器N1、N2……Ni……Nn，它们的容积满足V1<V2<……<Vi<……<Vn；按照低通声滤波器容积从小到大的顺序，沿曲折声波主通道，布置由n个低通声滤波器组成的低通声滤波器组，在布置的n个低通声滤波器处，实现声波传播空间向主通道以外的低通声滤波器的空腔扩张，且扩张空间随主通道深度的增加而变大，进而在n个低通声滤波器N1、N2……Ni……Nn处，依次实现高频到低频声波的反射；
沿声波主通道布置的低通声滤波器，根据设计需求，可在滤波器的一个或多个空腔与声波主通道之间布置细支管，在保留滤波器的空腔和声波主通道原有通路的基础上，增加额外的通路；
在低通声滤波器的空腔和声波主通道之间起连通作用的细支管，或者延伸至空腔和声波主通道内部，或者不延伸；在低通声滤波器的多个空腔之间起连通作用的细支管，或者延伸至空腔内部，或者不延伸；对于仅包含单空腔的低通声滤波器，当其空腔与声波主通道直接相通时，与空腔连通的声波主通道或者延伸至空腔内部，或者不延伸；对于包含多空腔的低通声滤波器，当声滤波器的接口空腔与声波主通道直接相通时，与接口空腔连通的声波主通道或者延伸至空腔内部，或者不延伸；
所述低通声滤波器组宽频吸声体最主要的特点是：采用一条声波主通道，满足一张微穿孔板对吸收不同中心频带声波的相位传播延迟的要求，实现从低频到高频超宽带吸声，同时结合声波主通道曲折布置，实现超薄的结构尺寸。
附图说明
图1是低通声滤波器组宽频吸声体示意图。
图2是低通声滤波器组宽频吸声体示意图。
图3是低通声滤波器组宽频吸声体示意图。
图4是“L”形声波主通道示意图。
图5是“U”形声波主通道示意图。
图6是螺旋形声波主通道示意图。
图7是蛇形声波主通道示意图。
图8是三层声波主通道示意图。
图9是由单腔和一段变截面声波主通道构成的低通声滤波器。
图10是由单腔、细支管和一段等截面声波主通道构成的低通声滤波器。
图11是由单腔和一段变截面声波主通道构成的低通声滤波器。
图12是由单腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图13是由单腔和一段等截面声波主通道构成的低通声滤波器。
图14是由单腔和一段等截面声波主通道构成的低通声滤波器。
图15是由双腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图16是由双腔、细支管和一段等截面声波主通道构成的低通声滤波器。
图17是由双腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图18是由双腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图19是由双腔、细支管和一段等截面声波主通道构成的低通声滤波器。
图20是：由双腔、细支管和一段等截面声波主通道构成的低通声滤波器。
图21是由双腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图22是由双腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图23是由双腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图24是由三腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图25是由三腔、细支管和一段等截面声波主通道构成的低通声滤波器。
图26是由三腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图27是由五腔、细支管和一段变截面声波主通道构成的低通声滤波器。
图中：
1.微穿孔板；2.微穿孔板后空腔；3.声波主通道始端(微穿孔板后空腔末端)；4.声波主通道；5.声波主通道末端；6.沿声波主通道布置的低通声滤波器；7.细支管；8.低通声滤波器接口空腔；9.低通声滤波器辅助空腔；
11.沿声波主通道布置的第1个低通声滤波器；12.沿声波主通道布置的第2 个低通声滤波器；13.沿声波主通道布置的第3个低通声滤波器；14.沿声波主通道布置的第4个低通声滤波器；15.沿声波主通道布置的第5个低通声滤波器；16.沿声波主通道布置的第6个低通声滤波器；17.第1层声波主通道；18.第2层声波主通道；19.第3层声波主通道；20.多层声波主通道相邻层间通道的连通孔；
注：图中箭头表示声波的传播方向。
具体实施方式
实施例1：如图1所示
低通声滤波器组宽频吸声体由一张微穿孔板1、微穿孔板后空腔2、与板后空腔2相通的一条曲折声波主通道4，以及沿曲折声波主通道4布置的低通声滤波器组构成；
所述微穿孔板1，一侧为外部声波入射端，另一侧后布置有空腔2，空腔2由侧壁围成，空腔2的容积根据微穿孔板1的面积乘以其穿孔率的数值结果估算，空腔2末端与声波主通道始端3相接相通；外部入射的声波通过微穿孔板1进入其后的空腔2，而后由空腔2进入声波主通道4；
所述的曲折声波主通道4，为近似U形的变截面单层通道，在通道的局部布置多孔吸声材料，声波主通道末端5封闭；
从声波主通道入口3开始，沿声波主通道4布置低通声滤波器组；低通声滤波器组由6个低通声滤波器11、12、13、14、15和16组成；低通声滤波器12和13，分别由单空腔和与空腔相通一段等截面声波主通道构成，单空腔与声波主通道直接相通；低通声滤波器11、14、15和16，分别由单空腔和与空腔相通的一段变截面声波主通道构成，单空腔与声波主通道直接相通；低通声滤波器11、12、13、14、15和16的截止频率分别为f1、f2、f3、f4、f5和f6，满足f1>f2>f3>f4>f5>f6；用V1、V2、V3、V4、V5和V6分别表示低通声滤波器11、12、13、14、15和16的等效容积，它们满足V1<V2<V3<V4<V5<V6；第1个低通声滤波器11，布置在声波主通道始端3附近，它的截止频率f1最高，容积V1最小；第6个低通声滤波器16，布置在声波主通道末端5附近，它的截止频 率f6最小，容积V6最大；
来自曲折主通道4的声波，在经过与主通道4连通的低通声滤波器11、12、13、14、15和16时被分流，一部分进入低通声滤波器的空腔或被吸收或被反射，一部分沿声波主通道4继续传播，如图1中箭头所示；
沿曲折声波主通道4布置与主通道相通的6个低通声滤波器，在布置的低通声滤波器11、12、13、14、15和16处，实现将声波的传播空间向主通道4以外扩张，且扩张空间随主通道4深度的增加而变大，进而在6个低通声滤波器11、12、13、14、15和16处，依次实现高频到低频声波的反射。
实施例2：如图2所示
实施例2与实施例1基本相同，主要区别是：
低通声滤波器13，由单空腔和与空腔相通的一段变截面声波主通道构成；
低通声滤波器14，由单空腔和与空腔相通的一段变截面声波主通道构成，且变截面声波主通延伸至空腔的内部；
低通声滤波器15，由接口空腔8、辅助空腔9、连通双空腔8和9的细支管7，以及与接口空腔8相通的一段等截面声波主通道构成，细支管7延伸至空腔内；
低通声滤波器16，由接口空腔8、辅助空腔9、连通双空腔8和9的细支管7，以及与接口空腔8相通的一段变截面声波主通道构成，细支管7不延伸；
在低通声滤波器16的双腔8和9中布置多孔吸声材料。
实施例3：如图3所示
低通声滤波器组宽频吸声体由一张微穿孔板1、微穿孔板后空腔2、与板后空腔2相通的一条曲折声波主通道4，以及沿曲折声波主通道4布置的低通声滤波器组构成；
所述微穿孔板1，一侧为外部声波入射端，另一侧后布置有空腔2，空腔2由侧壁围成，空腔2的容积根据微穿孔板1的面积乘以其穿孔率的数值结果估算，空腔2末端与声波主通道始端3相接相通；外部入射的声波通过微穿孔板1进入其后的空腔2，而后由空腔2进入声波主通道4；
所述的曲折声波主通道4，为等截面曲折单层通道，声波主通道末端5封闭；
从声波主通道入口3开始，沿声波主通道4布置低通声滤波器组；低通声滤波器组由5个低通声滤波器11、12、13、14和15组成；低通声滤波器11和12，分别由环形单空腔和与空腔相通的一段等截面声波主通道构成，空腔与声波主通道4直接相通；低通声滤波器13和14，分别由1个接口空腔8、1个辅助空腔9、连通双空腔的细支管7，以及与接口空腔8相通的一段等截面声波主通道构成，低通声滤波器13和14的接口空腔8分别与声波主通道4直接相通；低通声滤波器15，由1个接口空腔8、2个辅助空腔9、连通三空腔的两个细支管7，以及与接口空腔8相通的一段等截面声波主通道构成，低通声滤波器15的接口空腔8与声波主通道4通过细支管连通，连通空腔8与声波主通道4的细支管不延伸，连通空腔8和9的细支管不延伸，连通2个辅助空腔9的细支管7延伸至空腔内部；5个低通声滤波器11、12、13、14和15的截止频率分别为f1、f2、f3、f4和f5，满足f1>f2>f3>f4>f5；用V1、V2、V3、V4和V5分别表示低通声滤波器11、12、13、14和15的等效容积，它们满足V1<V2<V3<V4<V5；第1个低通声滤波器11布置在声波主通道始端3附近，它的截止频率f1最高，容积V1最小；第5个低通声滤波器15布置在声波主通道末端5附近，它的截止频率f5最小，容积V5最大；
来自曲折主通道4的声波，在经过与主通道4连通的低通声滤波器11、12、13、14和15时被分流，一部分进入低通声滤波器的空腔或被吸收或反射，一部分沿声波主通道4继续传播，如图中箭头所示；
沿曲折声波主通道4布置与主通道相通的5个低通声滤波器，在布置的低通声滤波器11、12、13、14和15处，实现将声波的传播空间向主通道4以外扩张，且扩张空间随主通道4深度的增加而变大，进而在5个低通声滤波器11、12、13、14和15处依次实现高频到低频声波的反射。
在通道中低通声滤波器的附近，布置多孔吸声材料。
实施例4：
实施例4与实施例1基本相同，主要区别是：
曲折声波主通道4，采用如图4、图5、图6或图7的型式。
实施例5：
实施例5与实施例3基本相同，主要区别是：
曲折声波主通道4采用3层叠加的螺旋形布置型式，如图8所示，在相邻层之间布置通道连通孔20，以保证声波主通道从始端3到末端5连通，曲折声波主通道4为变截面通道；
单腔低通声滤波器11和12，采用如图9、图10、图11、图12、图13或图14的型式；
双腔低通声滤波器13和14，采用如图15、图16、图17、图18、图19、图20、图21、图22或图23的型式；
三腔低通声滤波器15，采用如图24、图25或图26的型式。
实施例6：
实施例6与实施例3基本相同，主要区别是：
曲折声波主通道4为变截面通道；
用五腔低通声滤波器替代三腔低通声滤波器15，五腔低通声滤波器如图27所示，它由2个接口空腔8、3个辅助空腔9、连通空腔的细支管7，以及与接口空腔8相通的一段变截面声波主通道构成。

Claims (3)

  1. 一种低通声滤波器组宽频吸声体，其特征是：包括一张微穿孔板、微穿孔板后空腔、与板后空腔相通的一条曲折声波主通道，以及沿曲折声波主通道布置的低通声滤波器组；
    所述微穿孔板，板厚不大于2mm，穿孔直径不大于0.5mm，穿孔率不大于5％；微穿孔板一侧为外部声波入射端，另一侧后布置有空腔，空腔由侧壁围成，空腔容积根据微穿孔板面积乘以穿孔率的数值结果估算，空腔末端与声波主通道的始端相通；外部入射的声波通过微穿孔板进入其后的空腔，而后由空腔进入声波主通道；
    所述曲折声波主通道，为迂回、弯曲、盘绕或螺旋形的通道；声波主通道为变截面通道或等截面通道；声波主通道在低通声滤波器组宽频吸声体中，以单层或多层的型式紧密布置；声波主通道始端与微穿孔板后空腔的末端相通，声波主通道末端封闭；当曲折声波主通道在吸声体中以多层型式布置时，相邻层之间的通道相通，保证声波主通道从始端到末端连通；单层或多层的曲折声波主通道中，布置吸声材料或不布置吸声材料；
    所述的低通声滤波器组由多个具有不同截止频率的低通声滤波器组成；声滤波器按照截止频率从高到低的顺序沿曲折的声波主通道布置，用Ni(i＝1、2……n)表示第i个低通声滤波器，用fi(i＝1、2……n)表示第i个低通声滤波器Ni的截止频率，则从声波主通道入口开始，沿声波主通道依次布置低通声滤波器N1、N2……Ni……Nn，这些低通声滤波器的截止频率满足f1>f2>……>fi>……>fn；第1个低通声滤波器N1的截止频率f1最高，布置在声波主通道始端附近；最后一个低通声滤波器Nn的截止频率fn最低，布置在声波主通道末端附近；
    所述的沿曲折声波主通道布置的每个低通声滤波器，由至少一个空腔和与空 腔相通的一段声波主通道构成；每个空腔或者由多个自由曲面围成，或者由多个平面围成，或者由多个曲面和平面共同围成，空腔中布置吸声材料或者不布置吸声材料；对于仅包括单空腔的低通声滤波器，单空腔或者与声波主通道直接相通，或者在单空腔和声波主通道之间布置细支管，使单空腔通过细支管与声波主通道相通；对于包括多个空腔的低通声滤波器，定义与声波主通道邻近的空腔为接口空腔，接口空腔或者与声波主通道直接相通，或者在接口空腔和声波主通道之间布置细支管使其与声波主通道相通，接口空腔的作用是引导来自曲折主通道的声波传入低通声滤波器，或引导低通声滤波器中的声波传出声滤波器进入曲折主通道；对于包括多个空腔的低通声滤波器，多个空腔之间通过一个或多个细支管连通，以保证低通声滤波器的所有空腔和声波主通道连通；来自曲折主通道的声波，在经过与主通道连通的低通声滤波器时被分流，一部分进入低通声滤波器的空腔或被吸收或被反射，一部分沿声波主通道继续传播；所述的沿曲折声波主通道布置的低通声滤波器组，定义每个低通声滤波器所有空腔容积的等效和为该低通声滤波器的容积，用Vi表示低通声滤波器Ni(i＝1、2、3……n)的容积；从声波主通道入口开始，按照截止频率从高到低的顺序，沿曲折声波主通道布置n个低通声滤波器N1、N2……Ni……Nn，它们的容积满足V1<V2<……<Vi<……<Vn；按照低通声滤波器容积从小到大的顺序，沿曲折声波主通道，布置由n个低通声滤波器组成的低通声滤波器组，在布置的n个低通声滤波器处，实现声波传播空间向主通道以外的低通声滤波器的空腔扩张，且扩张空间随主通道深度的增加而变大，进而在n个低通声滤波器N1、N2……Ni……Nn处，依次实现高频到低频声波的反射；
    所述低通声滤波器组宽频吸声体采用一条声波主通道，满足一张微穿孔板对吸收不同中心频带声波的相位传播延迟的要求，实现从低频到高频超宽带吸 声，同时结合声波主通道曲折布置，实现超薄的结构尺寸。
  2. 如权利要求1所述的一种低通声滤波器组宽频吸声体，其特征是：沿声波主通道布置的每个低通声滤波器，在滤波器包括的空腔与声波主通道之间至少有一个通路。
  3. 如权利要求1和2所述的一种低通声滤波器组宽频吸声体，其特征是：在低通声滤波器的空腔和声波主通道之间起连通作用的细支管，或者延伸至空腔和声波主通道内部，或者不延伸；在低通声滤波器的多个空腔之间起连通作用的细支管，或者延伸至空腔内部，或者不延伸；对于仅包含单空腔的低通声滤波器，当其空腔与声波主通道直接相通时，与空腔连通的声波主通道或者延伸至空腔内部，或者不延伸；对于包含多空腔的低通声滤波器，当声滤波器的接口空腔与声波主通道直接相通时，与接口空腔连通的声波主通道或者延伸至空腔内部，或者不延伸。
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107071663A (zh) * 2017-04-26 2017-08-18 大连理工大学 宽带超薄声波扩散结构
CN110503936A (zh) * 2019-08-13 2019-11-26 安徽建筑大学 一种可调亚波长低频吸声结构
US20190378490A1 (en) * 2017-04-26 2019-12-12 Dalian University Of Technology Broadband ultrathin sound absorption or sound insulation structure controlling an acoustic wave propagation path
WO2020098477A1 (zh) * 2018-11-15 2020-05-22 中车株洲电力机车有限公司 一种低频耦合吸声结构
CN111402852A (zh) * 2019-01-02 2020-07-10 香港科技大学 频率离散主动面板的低频吸声和软边界效应

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101727894B (zh) * 2010-01-08 2012-05-23 中国科学院声学研究所 一种内置共振腔体的复合吸声装置
CN112049269B (zh) * 2020-08-19 2023-01-24 中国铁路设计集团有限公司 一种组合频带式吸声复合结构

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107071663A (zh) * 2017-04-26 2017-08-18 大连理工大学 宽带超薄声波扩散结构
US20190378490A1 (en) * 2017-04-26 2019-12-12 Dalian University Of Technology Broadband ultrathin sound absorption or sound insulation structure controlling an acoustic wave propagation path
WO2020098477A1 (zh) * 2018-11-15 2020-05-22 中车株洲电力机车有限公司 一种低频耦合吸声结构
CN111402852A (zh) * 2019-01-02 2020-07-10 香港科技大学 频率离散主动面板的低频吸声和软边界效应
CN110503936A (zh) * 2019-08-13 2019-11-26 安徽建筑大学 一种可调亚波长低频吸声结构

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4174843A4 *

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