CN116856569B - 一种超通风声学超材料消音罩 - Google Patents

一种超通风声学超材料消音罩

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CN116856569B
CN116856569B CN202310824691.6A CN202310824691A CN116856569B CN 116856569 B CN116856569 B CN 116856569B CN 202310824691 A CN202310824691 A CN 202310824691A CN 116856569 B CN116856569 B CN 116856569B
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absorbing
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channel
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CN116856569A (zh
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黄映洲
吴朝林
王力
史海洋
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Chongqing University
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    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, 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
    • E04B1/84Sound-absorbing elements
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, 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
    • E04B1/8209Heat, 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 sound absorbing devices
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, 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
    • E04B1/84Sound-absorbing elements
    • E04B1/8409Sound-absorbing elements sheet-shaped
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, 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
    • E04B1/84Sound-absorbing elements
    • E04B2001/8423Tray or frame type panels or blocks, with or without acoustical filling
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, 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
    • E04B1/84Sound-absorbing elements
    • E04B2001/8423Tray or frame type panels or blocks, with or without acoustical filling
    • E04B2001/8433Tray or frame type panels or blocks, with or without acoustical filling with holes in their face
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, 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
    • E04B1/84Sound-absorbing elements
    • E04B2001/8457Solid slabs or blocks
    • E04B2001/8476Solid slabs or blocks with acoustical cavities, with or without acoustical filling
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04BGENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82Heat, 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
    • E04B1/84Sound-absorbing elements
    • E04B2001/8457Solid slabs or blocks
    • E04B2001/8476Solid slabs or blocks with acoustical cavities, with or without acoustical filling
    • E04B2001/848Solid slabs or blocks with acoustical cavities, with or without acoustical filling the cavities opening onto the face of the element

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  • Acoustics & Sound (AREA)
  • Engineering & Computer Science (AREA)
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Abstract

本发明提出了一种超通风声学超材料消音罩,包括消音罩骨架,消音罩骨架为立式矩形框架结构,消音罩骨架的各裸露面均通过至少一个方形管充满,以形成通风吸声墙;方形管贯通消音罩内、外,在方形管的内壁一圈铺有声学超材料吸声贴片,且内壁的一圈声学超材料吸声贴片围成通风降噪通道;单个声学超材料吸声贴片包括贴片外壳,其内设有呈水平矩阵排列的多个超材料吸声单元,单个超材料吸声单元包括至少四个超材料吸声结构,各超材料吸声结构关于超材料吸声单元的中心旋转对称;在贴片外壳的顶面对应每个超材料吸声单元的中心位置处均设有吸声入口,每个超材料吸声结构分别与吸声入口相通。本发明能同时解决噪声装置的消声与散热问题。

Description

一种超通风声学超材料消音罩
技术领域
本发明涉及消音罩技术领域,特别涉及一种超通风声学超材料消音罩。
背景技术
目前大多数装置利用传统吸声材料如吸音棉、吸声泡沫和多孔板等结构来搭建噪音装置的隔音墙。为了能让噪音装置产生的热量耗散,只能在几个面上放置隔音板,其他面则敞开,所以部分声音会从敞开的面向外传播,吸声效果大打折扣,即现有隔音装置存在不能同时兼顾高效通风散热和高效吸声的问题。声学超材料与电磁(包括光)超材料类似,是人工制造具有负等效质量密度和负等效模量的人工亚波长的一种复合结构。由于它结构尺寸单元远小于声波波长,具有很多自然材料所不具备的特殊性质,极大地扩展了声学材料的作用及其应用领域。在低频噪声领域中,由于低频噪声声波较长、传播距离远、衰落弱等特点,对其有效控制一直是噪声控制领域有挑战性的难题。声学超材料的出现,弥补了传统的线性隔声材料应对低频噪声问题上的缺陷,表现出了良好的低频降噪性能。
发明内容
针对上述现有技术中存在的问题,本发明旨在提供一种超通风声学超材料消音罩,以同时解决噪音装置的消声与散热问题。
为了实现上述目的,本发明提出了一种超通风声学超材料消音罩,包括消音罩骨架,所述消音罩骨架为立式矩形框架结构,所述消音罩骨架的各裸露面均通过至少一个方形管充满,以形成通风吸声墙;所述方形管贯通消音罩内、外,在方形管的内壁一圈铺有声学超材料吸声贴片,且内壁的一圈声学超材料吸声贴片围成通风降噪通道;
单个所述声学超材料吸声贴片包括贴片外壳,所述贴片外壳内设有呈水平矩阵排列的多个超材料吸声单元,各所述超材料吸声单元紧密连接;单个超材料吸声单元包括至少四个超材料吸声结构,各所述超材料吸声结构关于超材料吸声单元的中心旋转对称;在贴片外壳的顶面对应每个超材料吸声单元的中心位置处均设有吸声入口,每个超材料吸声结构分别与吸声入口相通。
上述方案中:所述超材料吸声结构为复合亥姆霍兹谐振腔,所述复合亥姆霍兹谐振腔由两个内嵌共振腔串联而成,所述内嵌共振腔内设有环形通道,所述环形通道内包裹有一矩形腔,且矩形腔与环形通道相通。声波能量可进入吸声超材料贴片内的亥姆霍兹谐振腔里实现共振消耗,达到消声的目的。
上述方案中:所述超材料吸声结构为迷宫结构,所述迷宫结构的内部设有锯齿状通道,所述锯齿状通道与吸声入口相通。声波进入吸声学超材料吸声单元后在狭窄的锯齿状通道内传播,当声波频率与结构的固有频率接近时,会产生共振,在通道内剧烈震荡,由声波与通道壁间的热粘性损耗和摩擦损耗,将声能转化为热能并耗散掉,从而实现消声的效果;锯齿结构通过折叠声音传播的路径,可以很方便的改变吸声单元的共振频率。
上述方案中:所述锯齿状通道借助若干交错设置的锯齿形成,相邻两锯齿之间设有通道间距,锯齿状通道更有利于吸声降噪。
上述方案中:单个所述声学超材料吸声贴片的内部由至少两行两列排列的4个声学超材料吸声单元组成,通过相邻单元间的弱耦合,可以实现声音的低频高效吸收。
上述方案中:所述锯齿状通道通过水平设置的吸声通道与吸声入口相通,当锯齿状通道的宽度为l,吸声入口的宽度为k,吸声通道的宽度为a,单个声学超材料吸声单元内的锯齿数量为n,锯齿壁厚为w时,相邻两锯齿之间的间距d=(k+w+l-a-n*w)/n。
上述方案中:所述声学超材料吸声贴片的厚度不超过3cm,超薄的结构,可以使方形管内的流体近乎完美的自由流通以及实现方形管的小型化,有利于获得较大的通风比。
本发明的有益效果是:声波能量可进入吸声超材料贴片内的超材料吸声单元里实现消耗,达到消声的目的,再通过相邻超材料吸声单元间的弱耦合,实现准完美吸声或者实现宽频吸声;本发明基于声学超材料吸声原理,通过将通风吸声超材料搭建成一面墙,再利用这种通风吸声墙从各个方向将噪声装置罩住,能同时解决噪声装置的消声与散热问题;通过参数调节,通风面积比可达到80%以上,吸声率可超过90%。
附图说明
图1是本发明的结构示意图。
图2是声学超材料吸声贴片安装于方形管内部的示意图。
图3是声学超材料吸声贴片的外部结构示意图。
图4是声学超材料吸声贴片的一种内部结构示意图。
图5是图4中单个超材料吸声单元的结构示意图。
图6是声学超材料吸声贴片的另一种内部结构示意图。
图7是图6中单个超材料吸声单元的结构示意图。
具体实施方式
如图1—7所示,一种超通风声学超材料消音罩,主要由消音罩骨架1、方形管2和声学超材料吸声贴片3组成。图2中箭头方向为方形管2的通风方向。
消音罩骨架1为立式矩形框架结构,其罩设于噪音装置外侧。
消音罩骨架1的各裸露面均通过至少一个方形管2充满,以形成通风吸声墙;方形管2贯通消音罩内、外,在方形管2的内壁一圈铺有声学超材料吸声贴片3,且内壁的一圈声学超材料吸声贴片3围成通风降噪通道。
在不影响散热的情况下,为了节约成本,可以选择只放置其中部分面上的通风吸声墙,但为了充分降噪,避免声音泄露,其他不放置通风吸声墙的面选择用硬性背板代替。
单个声学超材料吸声贴片3包括贴片外壳33,贴片外壳33内设有呈水平矩阵排列的多个超材料吸声单元31,各超材料吸声单元31紧密连接。单个超材料吸声单元31包括至少四个超材料吸声结构32,各超材料吸声结构32关于超材料吸声单元31的中心旋转对称。
在贴片外壳33的顶面对应每个超材料吸声单元31的中心位置处均设有吸声入口A,每个超材料吸声结构32分别与吸声入口A相通。
最好是,超材料吸声结构32为复合亥姆霍兹谐振腔,复合亥姆霍兹谐振腔由两个内嵌共振腔34串联而成,内嵌共振腔34内设有环形通道D,环形通道D内包裹有一矩形腔35,且矩形腔35与环形通道D相通。声波能量可进入吸声超材料贴片内的亥姆霍兹谐振腔里实现共振消耗,达到消声的目的。
最好是,超材料吸声结构32为迷宫结构,迷宫结构的内部设有锯齿状通道B,锯齿状通道B与吸声入口A相通。声波进入吸声学超材料吸声单元31后在狭窄的锯齿状通道B内传播,当声波频率与结构的固有频率接近时,会产生共振,在通道内剧烈震荡,由声波与通道壁间的热粘性损耗和摩擦损耗,将声能转化为热能并耗散掉,从而实现消声的效果;锯齿结构通过折叠声音传播的路径,可以很方便的改变吸声单元的共振频率。
最好是,锯齿状通道B借助若干交错设置的锯齿321形成,相邻两锯齿321之间设有通道间距,锯齿状通道B更有利于吸声降噪。
最好是,单个声学超材料吸声贴片3的内部由至少两行两列排列的4个声学超材料吸声单元31组成,通过相邻单元间的弱耦合,可以实现声音的低频高效吸收。
最好是,锯齿状通道B通过水平设置的吸声通道C与吸声入口A相通,当锯齿状通道B的宽度为l,吸声入口A的宽度为k,吸声通道C的宽度为a,单个声学超材料吸声单元31内的锯齿321数量为n,锯齿321壁厚为w时,相邻两锯齿321之间的间距d=(k+w+l-a-n*w)/n。
最好是,声学超材料吸声贴片3的厚度不超过3cm,超薄的结构,可以使方形管2内的流体近乎完美的自由流通以及实现方形管2的小型化,有利于获得较大的通风比。

Claims (5)

1.一种超通风声学超材料消音罩,其特征在于:包括消音罩骨架(1),所述消音罩骨架(1)为立式矩形框架结构,所述消音罩骨架(1)的各裸露面均通过至少一个方形管(2)充满,以形成通风吸声墙;所述方形管(2)贯通消音罩内、外,在方形管(2)的内壁一圈铺有声学超材料吸声贴片(3),且内壁的一圈声学超材料吸声贴片(3)围成通风降噪通道;
单个所述声学超材料吸声贴片(3)包括贴片外壳(33),所述贴片外壳(33)内设有呈水平矩阵排列的多个超材料吸声单元(31),各所述超材料吸声单元(31)紧密连接;单个超材料吸声单元(31)包括至少四个超材料吸声结构(32),各所述超材料吸声结构(32)关于超材料吸声单元(31)的中心旋转对称;在贴片外壳(33)的顶面对应每个超材料吸声单元(31)的中心位置处均设有吸声入口(A),每个超材料吸声结构(32)分别与吸声入口(A)相通;
所述超材料吸声结构(32)为复合亥姆霍兹谐振腔或迷宫结构;
所述复合亥姆霍兹谐振腔由两个内嵌共振腔(34)串联而成,所述内嵌共振腔(34)内设有环形通道(D),所述环形通道(D)内包裹有一矩形腔(35),且矩形腔(35)与环形通道(D)相通;所述迷宫结构的内部设有锯齿状通道(B),所述锯齿状通道(B)与吸声入口(A)相通。
2.根据权利要求1所述的超通风声学超材料消音罩,其特征在于:所述锯齿状通道(B)借助若干交错设置的锯齿(321)形成,相邻两锯齿(321)之间设有通道间距。
3.根据权利要求1所述的超通风声学超材料消音罩,其特征在于:单个所述声学超材料吸声贴片(3)的内部由至少两行两列排列的4个声学超材料吸声单元(31)组成。
4.根据权利要求2所述的超通风声学超材料消音罩,其特征在于:所述锯齿状通道(B)通过水平设置的吸声通道(C)与吸声入口(A)相通,当锯齿状通道(B)的宽度为l,吸声入口(A)的宽度为k,吸声通道(C)的宽度为a,单个声学超材料吸声单元(31)内的锯齿(321)数量为n,锯齿(321)壁厚为w时,相邻两锯齿(321)之间的间距d=(k+w+l-a-n*w)/n。
5.根据权利要求1所述的超通风声学超材料消音罩,其特征在于:所述声学超材料吸声贴片(3)的厚度不超过3cm。
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