WO2000061888A1 - Materiau absorbant, constitue d'une matiere poreuse a double porosite - Google Patents
Materiau absorbant, constitue d'une matiere poreuse a double porosite Download PDFInfo
- Publication number
- WO2000061888A1 WO2000061888A1 PCT/FR2000/000912 FR0000912W WO0061888A1 WO 2000061888 A1 WO2000061888 A1 WO 2000061888A1 FR 0000912 W FR0000912 W FR 0000912W WO 0061888 A1 WO0061888 A1 WO 0061888A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- porosity
- absorbent material
- perforations
- range
- panel
- Prior art date
Links
- 239000000463 material Substances 0.000 title claims abstract description 48
- 230000002745 absorbent Effects 0.000 title claims abstract description 18
- 239000002250 absorbent Substances 0.000 title claims abstract description 18
- 238000010521 absorption reaction Methods 0.000 claims description 24
- 239000011148 porous material Substances 0.000 claims description 9
- 239000006260 foam Substances 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 230000035699 permeability Effects 0.000 description 3
- 239000012814 acoustic material Substances 0.000 description 2
- 239000011491 glass wool Substances 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 1
- 230000001143 conditioned effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000002045 lasting effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002557 mineral fiber Substances 0.000 description 1
- 239000011490 mineral wool Substances 0.000 description 1
- 210000000056 organ Anatomy 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000009182 swimming Effects 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
- 210000002268 wool Anatomy 0.000 description 1
Classifications
-
- 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
-
- 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
- E04B2001/848—Solid slabs or blocks with acoustical cavities, with or without acoustical filling the cavities opening onto the face of the element
- E04B2001/849—Groove or slot type openings
-
- 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
- E04B2001/848—Solid slabs or blocks with acoustical cavities, with or without acoustical filling the cavities opening onto the face of the element
- E04B2001/8495—Solid slabs or blocks with acoustical cavities, with or without acoustical filling the cavities opening onto the face of the element the openings going through from one face to the other face of the element
Definitions
- Absorbent material consisting of a porous material with double porosity
- the present invention relates to an improvement made to acoustic and sound absorption materials.
- It relates more particularly to absorbent porous materials intended for buildings (wall coverings) and public works (anti-noise devices), for which it is desired to improve the performance of the products, in particular in terms of absorption coefficient, especially at the level of a specific frequency band.
- acoustic absorbent materials because of their properties, limit the amount of energy that is reflected.
- the sound absorption of this material is also a function of the sensitivity in terms of bandwidth of the receiving organ, which when it comes to the human ear, is between 20 and 20,000 Hz.
- bandwidth of the receiving organ which when it comes to the human ear, is between 20 and 20,000 Hz.
- materials are used which take the form of panels or of pulverulent products which are sprayed, and which are made from mineral glass wool, foam, fabric or rigid perforated panels.
- Japanese patent JP10-175263 which describes an absorbent material formed of a "sandwich" consisting in particular of a first layer of material provided with a plurality of orifices which open out within a plurality of cavities formed in a second layer backed by the first.
- this absorbent material works according to the Helmholtz principle, the energy of the sound waves dissipating in the cavities.
- absorbent materials can be used both outdoors and in a confined (indoor) environment.
- mineral wools and certain foams with open porosity a material is said to have open porosity when its pores are connected to each other and with the outside
- open porosity a material is said to have open porosity when its pores are connected to each other and with the outside
- they are used in acoustic correction applications of ceilings or false ceilings (installation in plenum) rather than in insulation of conventional walls.
- these products based on glass wool or foam have suitable absorption properties but have drawbacks which are of three types: - they are usually relatively fragile and therefore not very durable, in particular because of the low densities employed taking into account that we want to get a relatively high permeability and porosity, this mechanical fragility makes it difficult to install;
- American patent 4 113 053 discloses an acoustic absorption material formed from an inorganic porous material and comprising a plurality of perforations positioned at an angle less than 80 ° relative to a specific dimension of the material.
- these perforations have a cross section (square, circular or rectangular) with a surface that can reach several tens of mm 2 .
- DE 33 39 701 a soundproofing panel made of fibers and comprising a plurality of perforations arranged on its surface at an angle between 10 ° and 80 °.
- the cross section of these perforations can be chosen arbitrarily.
- the present invention therefore aims to overcome these drawbacks, by proposing improvements to acoustic materials which give them significant mechanical properties (mechanical resistance), even when these materials have a small thickness while retaining optimum acoustic absorption properties for them, especially in the area of low frequencies.
- the absorbent material consisting of a porous material with open porosity, comprising a plurality of perforations of varied cross section and positioned at an angle ⁇ relative to a specific dimension of the material, thus conferring added porosity (Pa ) to the material which is the subject of the invention characterized in that the added porosity (Pa) is included in a range of 10 to 30% and in that it comprises an absorption coefficient included in a range ranging between 0.7 and 0.95 approximately for low frequencies, of the order in particular of 300 Hz.
- FIG. 1 is a perspective view of an absorbent material according to a first embodiment of one invention
- Figure 2 is a sectional view in plan elevation of Figure 1;
- Figure 3 is a sectional view in side elevation of Figure 2;
- FIG. 4 is a perspective view of an absorbent material according to a second embodiment of the invention.
- Figure 5 is a sectional view in side elevation of Figure 4.
- FIG. 6 is a graph illustrating the evolution of the absorption coefficient of the panel which is the subject of the invention, for different values of the frequency according to various porosities;
- FIG. 7 is a graph illustrating the evolution of the absorption coefficient of the panel which is the subject of the invention, for different values of the frequency according to different values of the angle of inclination ⁇ ;
- FIGS. 1 and 4 illustrate two different embodiments of the acoustic material, the latter comprising a basic material represented by the reference 1 in the figures.
- This material is packaged in a nonlimiting manner in the form of panels or boards of suitable dimensions so that they can be easily handled by a single user.
- this material is porous and has an open porosity (an open porosity is defined as follows: the pores are connected to each other and to the outside.
- a material based on mineral wool, concrete with mineral fibers, wood or synthetics, or more generally foams exhibits this property.
- the size of the pores (represented by the reference 2 in FIGS. 1 and 4) is less than a millimeter.
- the flow of air within this material and the absorption of the corresponding acoustic wave through this material is a function of the dynamic permeability and the frequency of the wave.
- the dynamic permeability of this material is itself a function of the geometrical characteristics of the material and by modifying the geometrical properties of the panel 1, the absorption factors of an acoustic wave passing through it are acted upon.
- a plurality of additional perforations 3 are produced within the panel 1.
- the specific dimension of the perforation in the case of a circle: its diameter, and in the case of a rectangular profile slot: its width, can vary within a range of between 0.005 and 0.1 m approximately. .
- the porosity added to the single-porosity material using the aforementioned parameters (inclination and / or choice of the specific dimension of the perforation), as a function of the following equation where Pa represents the added porosity which is defined as follows, this being the ratio of the volume of the cylinders to the total volume of the panel.
- Pa represents the added porosity which is defined as follows, this being the ratio of the volume of the cylinders to the total volume of the panel.
- n number of perforations per m 2
- d specific dimension in meters
- ⁇ inclination of the perforation.
- a double porosity panel which is the subject of the invention has coefficients absorption significantly higher than those of the prior art panels (cf. Figures 6, 7 and 8), this absorption coefficient being between 0.8 and 0.95 approximately for frequency values between 400 and 600 Hz for Figures 6 and 7 and close to the range 225-350 Hz in Figure 8.
- the invention as described above offers multiple advantages because it can be implemented from single-porosity panels known from the prior art, the optimal results in terms of absorption coefficient being obtained for relatively porosity values. low, which is preferable when one wishes to benefit from a high mechanical strength, guaranteeing great ease of implementation and lasting results.
- the added porosity (Pa) of the absorbent material (1) is within a range of 10 to 30%.
- the absorption coefficient is within a range extending between 0.7 and 0.95 approximately for low frequencies, of the order in particular of 300 Hz. It remains of course that the present invention is not limited to the exemplary embodiments described and shown above, but that it encompasses all variants thereof.
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Multimedia (AREA)
- Electromagnetism (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Building Environments (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP00917175A EP1169526A1 (fr) | 1999-04-13 | 2000-04-10 | Materiau absorbant, constitue d'une matiere poreuse a double porosite |
US09/958,665 US6615951B1 (en) | 1999-04-13 | 2000-04-10 | Absorbent material, consisting of a porous substance with double porosity |
AU38271/00A AU3827100A (en) | 1999-04-13 | 2000-04-10 | Absorbent material, consisting of a porous matter with double porosity |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR99/04603 | 1999-04-13 | ||
FR9904603A FR2792348B1 (fr) | 1999-04-13 | 1999-04-13 | Materiau absorbant, constitue d'une matiere poreuse a double porosite |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2000061888A1 true WO2000061888A1 (fr) | 2000-10-19 |
Family
ID=9544336
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FR2000/000912 WO2000061888A1 (fr) | 1999-04-13 | 2000-04-10 | Materiau absorbant, constitue d'une matiere poreuse a double porosite |
Country Status (5)
Country | Link |
---|---|
US (1) | US6615951B1 (fr) |
EP (1) | EP1169526A1 (fr) |
AU (1) | AU3827100A (fr) |
FR (1) | FR2792348B1 (fr) |
WO (1) | WO2000061888A1 (fr) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2848232A1 (fr) * | 2002-12-10 | 2004-06-11 | Jean Luc Sandoz | Structure antibruit |
FR2917882A1 (fr) * | 2007-06-21 | 2008-12-26 | Renault Sas | Materiau absorbant comportant des cabites a peau resistive et procede pour la fabrication d'un tel materiau |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1607544B1 (fr) * | 2004-06-17 | 2009-04-15 | Heimbach GmbH & Co. KG | Dispositif d'amortissement du son pour un revêtement de mur, de plafond ou de sol |
EP1653021A1 (fr) * | 2004-10-30 | 2006-05-03 | Allan Stefan Wojcinski | Revêtement acoustique pour murs et plafonds, notamment pour stands de tir |
US20080216969A1 (en) * | 2005-03-03 | 2008-09-11 | Barkman Arthur P | Sound absorbing blind systems |
US20060196617A1 (en) * | 2005-03-03 | 2006-09-07 | Barkman Arthur P | Sound absorbing composite blind systems |
US20100326606A1 (en) * | 2005-03-03 | 2010-12-30 | Barkman Arthur P | Composite sound absorbing blind systems |
KR20080092838A (ko) * | 2007-04-12 | 2008-10-16 | 가부시끼 가이샤 구보다 | 캐빈을 구비한 주행 차량 |
DE102007022616C5 (de) * | 2007-05-15 | 2013-01-17 | Airbus Operations Gmbh | Mehrschichtplatte mit schräger Schlitzung des Plattenkerns zur Reduzierung der Körperschallabstrahlung und zur Erhöhung der Schalldämmung bei Beibehalten der mechanischen Stabilität |
KR20130060885A (ko) * | 2011-11-30 | 2013-06-10 | 삼성디스플레이 주식회사 | 충격 흡수 시트 및 이를 구비하는 표시 장치 |
WO2013153491A1 (fr) * | 2012-04-12 | 2013-10-17 | Koninklijke Philips N.V. | Élément de construction acoustique électroluminescent |
US9792891B2 (en) * | 2012-06-20 | 2017-10-17 | Philips Lighting Holding B.V. | Acoustic panel having lighting properties |
US9873105B2 (en) * | 2014-10-24 | 2018-01-23 | City University Of Hong Kong | Sorbent material and a method for enhancing sorption performance thereof |
CN105118497A (zh) * | 2015-09-18 | 2015-12-02 | 贵州大学 | 一种管束式穿孔板和弹簧环状结构吸声装置 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE520833C (de) * | 1925-05-16 | 1931-03-14 | Dahlberg & Company Inc | Schalldaempfende Bauplatte aus porigem Faserstoff |
DE2441164A1 (de) * | 1974-08-28 | 1976-03-11 | Loehlein Ziegelwerke Geb | Schallschluck-wandelement |
US4113053A (en) * | 1976-10-06 | 1978-09-12 | Bridgestone Tire Company Limited | Sound absorbing body |
DE3339701A1 (de) * | 1983-11-03 | 1985-05-23 | Karl 5249 Hamm Rische | Schalldaemmende und schalldaempfende platte |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR970706559A (ko) * | 1994-10-11 | 1997-11-03 | 사가라 아츠히코 | 흡음체, 흡음판 및 흡음유니트 |
JPH10175263A (ja) | 1996-12-18 | 1998-06-30 | Nikki Kogyo Kk | 吸音体 |
-
1999
- 1999-04-13 FR FR9904603A patent/FR2792348B1/fr not_active Expired - Lifetime
-
2000
- 2000-04-10 WO PCT/FR2000/000912 patent/WO2000061888A1/fr not_active Application Discontinuation
- 2000-04-10 US US09/958,665 patent/US6615951B1/en not_active Expired - Fee Related
- 2000-04-10 AU AU38271/00A patent/AU3827100A/en not_active Abandoned
- 2000-04-10 EP EP00917175A patent/EP1169526A1/fr not_active Withdrawn
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE520833C (de) * | 1925-05-16 | 1931-03-14 | Dahlberg & Company Inc | Schalldaempfende Bauplatte aus porigem Faserstoff |
DE2441164A1 (de) * | 1974-08-28 | 1976-03-11 | Loehlein Ziegelwerke Geb | Schallschluck-wandelement |
US4113053A (en) * | 1976-10-06 | 1978-09-12 | Bridgestone Tire Company Limited | Sound absorbing body |
DE3339701A1 (de) * | 1983-11-03 | 1985-05-23 | Karl 5249 Hamm Rische | Schalldaemmende und schalldaempfende platte |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2848232A1 (fr) * | 2002-12-10 | 2004-06-11 | Jean Luc Sandoz | Structure antibruit |
WO2004055284A1 (fr) * | 2002-12-10 | 2004-07-01 | Jean-Luc Sandoz | Structure antibruit |
FR2917882A1 (fr) * | 2007-06-21 | 2008-12-26 | Renault Sas | Materiau absorbant comportant des cabites a peau resistive et procede pour la fabrication d'un tel materiau |
WO2009004258A2 (fr) * | 2007-06-21 | 2009-01-08 | Renault S.A.S | Materiau absorbant comportant des cavites a peau resistive et procede pour la fabrication d'un tel materiau |
WO2009004258A3 (fr) * | 2007-06-21 | 2010-10-21 | Renault S.A.S | Materiau absorbant comportant des cavites a peau resistive et procede pour la fabrication d'un tel materiau |
Also Published As
Publication number | Publication date |
---|---|
AU3827100A (en) | 2000-11-14 |
FR2792348A1 (fr) | 2000-10-20 |
US6615951B1 (en) | 2003-09-09 |
FR2792348B1 (fr) | 2001-07-06 |
EP1169526A1 (fr) | 2002-01-09 |
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