Thermal and acoustic insulation assembly comprising a thermal and acoustic insulation product and a membrane located at the front face

Abstract

The invention relates to a thermal and acoustic insulation assembly comprising: a thermal and acoustic insulation product (1) made of mineral wool, said thermal and acoustic insulation product (1) comprising a first face, referred to as the front face (1a), intended to face the interior of a room, and a second face, referred to as the back face (1b), intended to face a wall (2), and a microperforated membrane (3) arranged on said front face (1a) of said thermal and acoustic insulation product (1). The invention makes it possible to significantly improve the sound absorption performance without reducing the sound insulation performance.

Description

Technical Field

[0001] The present invention relates to a thermal and acoustic insulation assembly for marine applications, such as ships, enabling the insulation of metal walls of the ship. Background Art

[0002] It is known to insulate this type of wall using thermal insulation products made of mineral wool, such as the Ultimate product sold by Saint-Gobain Isover. To improve the sound insulation effect, a film is placed on the front side of the thermal and sound insulating product, that is, on the side of the product facing the room to be insulated (opposite to the side intended to face the wall). This film generally has a density of 2 to 10 kg / m 2 and a surface density of 2000 to 2200 kg / m 3 The volume density of the membrane is significantly improved, resulting in a significant improvement in sound insulation. However, the main disadvantage of this membrane is that it is airtight, which has a negative impact on sound absorption. As a result, the noise level in the sound emission room can be significantly increased.

[0003] Therefore, there is a need for a thermal and acoustic insulation assembly comprising a thermal and acoustic insulation product and a membrane at the front face that significantly improves sound absorption without compromising sound insulation. Summary of the Invention

[0004] To this end, the present invention proposes a heat and sound insulation assembly, comprising:

[0005] - thermal and acoustic insulating products made of mineral wool, comprising a first side, called the front side, intended to face the interior of the room, and a second side, called the back side, intended to face the wall,

[0006] - Microperforated membrane arranged on the front face of the thermal and acoustic insulating product.

[0007] According to another feature, the microperforated membrane has an air flow resistance of between 0.5 kPa.s / m and 10 kPa.s / m, preferably between 1 kPa.s / m and 5 kPa.s / m.

[0008] According to another feature, the microperforated film has, for a thickness L, a perforation degree φ and a perforation diameter D such that φD 2 =32η × L / (σL), where σL represents the airflow resistance of the membrane, and η represents the dynamic viscosity of the air.

[0009] According to another particular feature, the microperforated film has:

[0010] - a degree of perforation between 0.01% and 5%, preferably between 0.05% and 2%, or even between 0.1% and 1%,

[0011] - a perforation radius between 0.01 and 0.5 mm, preferably between 0.1 and 0.25 mm.

[0012] According to another feature, the microperforated membrane has a surface density between 2 and 10 kg / m 2 between.

[0013] According to another characteristic, the density of the thermal and acoustic insulation product is 13 kg / m 3 and 200 kg / m 3 between, preferably between 13kg / m 3 and 100 kg / m 3 between, even at 24 kg / m 3 and 100 kg / m 3 between.

[0014] According to another feature, the thickness of the thermal and acoustic insulating product is between 10 mm and 150 mm, preferably between 15 mm and 150 mm, or even between 20 mm and 150 mm.

[0015] According to another feature, the thermal and acoustic insulating product consists essentially of aluminosilicate type glass fibers.

[0016] According to another feature, the microperforated film is at least partially adhered or bonded or mated to the front face of the thermal and acoustic insulation product.

[0017] According to another feature, the thermal and acoustic insulating assembly also comprises a surface made of mineral wool, which is arranged on the face of the microperforated membrane opposite to the thermal and acoustic insulating product.

[0018] According to another feature, the surface has a surface density of 0.01 kg / m 2 and 10 kg / m 2 between, preferably between 0.1 kg / m 2 and 5 kg / m 2 between.

[0019] According to another characteristic, the density of the surface is 20 kg / m 3 and 200 kg / m 3 between, preferably between 30 kg / m 3 and 150kg / m 3 between, even between 30 kg / m 3 and 90 kg / m 3 between.

[0020] According to another feature, the thickness of the surface is between 0.5 mm and 20 mm, preferably between 5 mm and 15 mm, or even between 5 mm and 15 mm.

[0021] The invention also relates to the use of the thermally and acoustically insulating assembly described above on the metal wall of a ship. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Other features and advantages of the present invention will now be described with reference to the accompanying drawings, in which:

[0023] Figure 1 A cross-sectional view showing a thermal and acoustic insulation assembly according to the invention mounted on a metal wall of a ship.

[0024] The same reference numbers in different drawings identify the same or similar elements. DETAILED DESCRIPTION

[0025] The present invention relates to a thermal and acoustic insulation assembly comprising:

[0026] - thermal and acoustic insulating products made of mineral wool, comprising a first side, called the front side, intended to face the interior of the room, and a second side, called the back side, intended to face the wall,

[0027] - Microperforated membrane arranged on the front face of the thermal and acoustic insulating product.

[0028] The micropores in the membrane enable control over both sound absorption and sound insulation. In effect, the membrane acts as a resistive curtain, enhancing wave dissipation in the thermal and acoustic insulation product behind it. Compared to an unperforated membrane, the presence of the micropores only slightly reduces sound insulation while improving sound absorption. The size and degree of perforation can be tailored to control both sound absorption and sound insulation. Low perforation limits degradation of insulation compared to prior art airtight membranes. Furthermore, the perforations are small in size to optimize energy dissipation through viscous friction of the air (moved by sound waves). Consequently, sound absorption is significantly enhanced.

[0029] Figure 1 A cross-sectional view of a thermal and acoustic insulation assembly according to the present invention is shown, mounted on a wall 2, such as the steel or aluminum metal wall of a ship. The thermal and acoustic insulation assembly comprises a thermal and acoustic insulation product 1 made of mineral wool. The thermal and acoustic insulation product 1 comprises a first side, referred to as the front side 1a, which is intended to face the interior of the room to be insulated, and a second side, referred to as the back side 1b, which is intended to face the wall 2 of the room to be insulated. In this figure, the back side 1b of the thermal and acoustic insulation product is placed against the wall 2.

[0030] The thermal and acoustic insulation product is made of glass wool or rock wool, for example consisting essentially of aluminosilicate glass fibers containing a weight fraction of aluminum oxide Al 2 O 3 between 13% and 28%.

[0031] The thermal and acoustic insulating assembly further comprises a microperforated membrane 3 positioned on the front face 1 a of the thermal and acoustic insulating product 1 made of mineral wool.

[0032] Microperforated membranes 3 typically have a strength between 2 and 10 kg / m 2 Therefore, it is a thick film that provides good sound insulation for thermal and acoustic insulation components.

[0033] The microperforated membrane 3 is typically a viscoelastic layer, optionally having at least one of the following properties:

[0034] - the structural damping η, which is equal to tan δ and is a function of frequency and is greater than or equal to 5% regardless of the frequency, and / or

[0035] - Young's modulus E, which is also a function of frequency and is less than or equal to 500 MPa. This "low" Young's modulus value gives the membrane a certain elasticity / workability, which is particularly useful for installation on the wall of a ship.

[0036] Typically, the microperforated membrane 3 has an air flow resistance of between 0.5 kPa.s / m and 10 kPa.s / m, preferably between 1 kPa.s / m and 5 kPa.s / m. The air flow resistance is measured according to standard ISO 9053.

[0037] The airflow resistance of the microperforated membrane 3 represents the limited ability of air to pass through it, likely due to the presence of micropores in the membrane. Because the airflow resistance of the microperforated membrane 3 is between 0.5 kPa.s / m and 10 kPa.s / m, it introduces energy dissipation through viscous friction in the air (moved by sound waves). As a result, absorption is significantly improved, particularly at low frequencies. If the airflow resistance is too low, sound attenuation due to internal friction is minimal, and the absorption provided by the membrane is low. However, the membrane's high permeability enables the waves to be absorbed by underlying thermal and acoustic insulation products. If the resistance is too high, most of the sound waves are reflected, and absorption is reduced. Typically, below 0.5 kPa.s / m, or even below 1 kPa.s / m, sound insulation deteriorates. Above 10 kPa.s / m, absorption no longer increases.

[0038] Preferably, for a thickness L, the microperforated membrane 3 also has a perforation degree φ and a perforation diameter D such that φD 2 = 32η × L / (σL), where σL represents the airflow resistance of the microperforated membrane and η represents the dynamic viscosity of air. For a given airflow resistance, the relationship between porosity and perforation diameter can therefore be defined. Microperforated membranes can be perforated with microperforations of various diameters. The perforations can have any geometric shape, such as circular, oval, or slot-shaped.

[0039] Thus, for example, the microperforated membrane 3 has:

[0040] - a porosity (percentage of pore surface area / total surface area) between 0.01% and 5%, preferably between 0.05% and 2%, or even between 0.1% and 1%,

[0041] - a perforation radius between 0.01 and 0.5 mm, preferably between 0.1 and 0.25 mm.

[0042] A perforation range between 0.01% and 5%, preferably between 0.05% and 2%, or even between 0.1% and 1%, makes it possible to optimize both sound insulation and sound absorption. At lower perforation values, the film tends to become airtight, while at higher perforation values, there is a risk of significantly reducing the insulation performance. Thus, a perforation range between 0.01% and 5% advantageously makes it possible to achieve an acceptable compromise between a significant gain in sound absorption and a very modest loss in sound insulation.

[0043] The microperforated membrane 3 is preferably at least partially bonded or joined or fitted to the front face 1a of the thermal and acoustic insulation product 1. The connection or bonding is preferably produced by an adhesive bond, for example in the form of glue dots or glue lines. The entire surface of the backing layer of the membrane does not necessarily have to be coated with adhesive.

[0044] Furthermore, the thermal and acoustic insulation product 1 generally has a 3 and 200 kg / m 3 The density is between 13kg / m 3 and 100 kg / m 3 between, even at 24 kg / m 3 and 100 kg / m 3 This density range confers sufficient mechanical strength properties to the thermal and acoustic insulation product for the intended application, namely the insulation of substantially vertical walls of ships.

[0045] The thermal and acoustic insulating product 1 also typically has a thickness between 10 mm and 150 mm, preferably between 15 mm and 150 mm, or even between 20 mm and 150 mm. This thickness range allows the thermal and acoustic insulating product to have good mechanical strength and, for the intended application, sufficient sound absorption.

[0046] Preferably, the thermal and acoustic insulating product 1 has a Young's modulus between 5 kPa and 2 MPa and a damping between 0% and 50%. Young's modulus and damping are measured according to ISO 18437 and according to the article "Polynomial relations for quasi-static mechanical characterization of isotropicporoelastic materials" by C. Langlois, R. Panneton, and N. Atalla, published in J. Acoust. Soc. Am., volume 110, pages 3032–3040, 2001. Young's modulus is important for sound insulation performance.

[0047] Optionally, the thermal and acoustic insulating component further includes a surface 6 made of mineral wool, which is disposed on the side of the microperforated membrane opposite the thermal and acoustic insulating product 1, and thus on the front side of the microperforated membrane 3, with the back side of the microperforated membrane 3 being positioned against the front side 1a of the thermal and acoustic insulating product 1. Surface 6 is a thin layer relative to the thermal and acoustic insulating product 1. Surface 6 further improves sound absorption, particularly at higher frequencies than the microperforated membrane 3.

[0048] The surface density of surface 6 is usually 0.01 kg / m 2 and 10 kg / m 2 between, preferably between 0.1 kg / m 2 and 5 kg / m 2 This range of surface density gives the surface 6 sound insulation properties.

[0049] The density of surface 6 is usually 20 kg / m 3 and 200 kg / m 3 between, preferably between 30 kg / m 3 and 150 kg / m 3 between, even between 30 kg / m 3 and 90 kg / m 3 This density range imparts mechanical strength properties to the surface 6.

[0050] The thickness of the surface 6 is generally between 0.5 mm and 20 mm, preferably between 5 mm and 15 mm, or even between 5 mm and 15 mm. This density range gives the surface 6 mechanical strength and sound-absorbing properties.

[0051] according to Figure 1In the embodiment shown in FIG, the assembly formed by the thermal and acoustic insulating product 1 and the microperforated membrane 3 is attached to the metal wall 2 by means of a pin 5 and a washer 4, the pin 5 passing through the washer 4, the microperforated membrane 3 and the thermal and acoustic insulating product 1 and embedded in the wall 2. When the surface 6 is present, the surface 6 can also be retained by the pin 4 and the washer 5, or as Figure 1 The surface 6 may also be bonded on top of the microperforated membrane as shown in FIG. The mating of the thermal and acoustic insulating assembly to the metal wall 2 may be accomplished by any other known means for attaching membranes to insulation products.

[0052] Three thermal and acoustic insulation assemblies were tested for their sound absorption and sound insulation properties:

[0053] - a first reference assembly comprising a thermal and acoustic insulating product and an airtight membrane;

[0054] - a second assembly comprising the same thermal and acoustic insulating product and a microperforated membrane according to the invention;

[0055] - A third assembly comprising the same thermal and acoustic insulating product, a microperforated membrane according to the invention and a surface.

[0056] The thermal and acoustic insulation product common to the three thermal and acoustic insulation components is a mineral wool board from Saint-Gobain Isover under the brand name Ultimate, having a density of 24 kg / m3 and a thickness of 50 mm.

[0057] The airtight membrane of the first thermal and acoustic insulating component has an airflow resistance of 70 kPa.s / m and is a membrane from Saint-Gobain Isover under the trademark SeaProtect dB Flex Alu.

[0058] The microperforated membrane of the second and third thermal and acoustic insulation components is the same membrane from Saint-Gobain Isover under the trademark SeaProtect dB Flex Alu, but is perforated. After perforation, its airflow resistance is 0.640 kPa.s / m, its thickness is 1.7 mm and its surface density is 3 kg / m 2 The perforation degree is 0.4%, and the micro-perforation radius is 0.319 mm. The surface density of the micro-perforated membrane is 3.25 kg / m 2 .

[0059] The surface of the third thermally and acoustically insulating component is the surface from Saint-Gobain Isover under the brand name Ultimate. Its surface density is 0.36 kg / m 2 , with a density of 24 kg / m 3 , and the thickness is 15 mm.

[0060] The first heat and sound insulation component has a sound absorption coefficient α of 0.05 W and 51 dB noise reduction R w .

[0061] The second thermal and acoustic insulation component has a sound absorption coefficient α of 0.25 W and 50 dB noise reduction R w .

[0062] The third thermal and acoustic insulation component has a sound absorption coefficient α of 0.65 W and 51 dB noise reduction R w .

[0063] The sound absorption coefficient and the sound insulation were measured on three products. The sound absorption coefficient α was measured according to ISO 354. S α is then calculated according to standard ISO 11654 W index.

[0064] The sound insulation is measured according to ISO 10140-2. R is then calculated according to ISO 717-1. w index.

[0065] A gain in sound absorption coefficient (α) of 0.2 was observed between the second thermally and acoustically insulating assembly (according to the invention) and the first thermally and acoustically insulating assembly (reference). W ) and -1dB sound insulation loss (R w ), a sound absorption coefficient gain (α ) of 0.6 was observed between the third thermally and acoustically insulating assembly (according to the present invention) and the first thermally and acoustically insulating assembly (reference). W ) without loss of sound insulation.

[0066] It has thus been demonstrated that the thermally and acoustically insulating assembly according to the invention clearly makes it possible to significantly improve the sound absorption performance while at the same time hardly or not at all reducing the sound insulation performance, this effect being even more pronounced when a surface is also present.

[0067] The invention also relates to the use of the thermally and acoustically insulating assembly according to the invention in a metal wall of a ship made of steel or aluminum, in order to significantly improve the sound absorption while hardly or not at all reducing the sound insulation inside the ship's interior.

Claims

1. A thermal and acoustic insulation assembly for marine applications, comprising: - a thermal and acoustic insulating product (1) made of mineral wool, comprising a first face, called the front face (1a), intended to face the interior of the room, and a second face, called the back face (1b), intended to face the wall (2), - a microperforated film (3) arranged on the front face (1a) of the thermal and acoustic insulating product (1), Characterized in that the microperforated membrane (3) is a viscoelastic layer, and wherein, for a thickness L, the microperforated membrane (3) has a perforation degree φ and a perforation diameter D such that φD 2 =32η×L / (σL), where σL represents the airflow resistance of the membrane, and η represents the dynamic viscosity of air.

2. The heat and sound insulation assembly according to claim 1, characterized in that The micro-perforated membrane (3) has: - a structural damping η greater than or equal to 5% whatever the frequency, and / or - a Young's modulus E, which is less than or equal to 500 MPa, whatever the frequency.

3. The heat and sound insulation assembly according to claim 1 or 2, characterized in that: The air flow resistance of the micro-perforated membrane (3) is between 0.5 kPa.s / m and 10 kPa.s / m.

4. The heat and sound insulation assembly according to claim 1 or 2, characterized in that: The micro-perforated membrane (3) has: - a degree of perforation between 0.01% and 5%, - Perforation radius between 0.01 and 0.5 mm.

5. The heat and sound insulation assembly according to claim 1 or 2, characterized in that: The surface density of the micro-perforated membrane (3) is between 2 and 10 kg / m 2 between.

6. The heat and sound insulation assembly according to claim 1 or 2, characterized in that: The density of the heat and sound insulation product (1) is 13 kg / m 3 and 200kg / m 3 between.

7. The heat and sound insulation assembly according to claim 1 or 2, characterized in that: The thickness of the heat-insulating and sound-insulating product (1) is between 10 mm and 150 mm.

8. The heat and sound insulation assembly according to claim 1 or 2, characterized in that: The heat and sound insulating product (1) mainly consists of aluminosilicate glass fibers.

9. The heat and sound insulation assembly according to claim 1 or 2, characterized in that: The microperforated membrane (3) is at least partially bonded or incorporated or fitted to the front face of the thermal and acoustic insulation product.

10. The heat and sound insulation assembly according to claim 1 or 2, characterized in that: It also comprises a surface (6) made of mineral wool, said surface (6) being arranged on the face of said microperforated membrane (3) opposite to said thermal and acoustic insulating product (1).

11. The thermal and acoustic insulation assembly according to claim 10, wherein: The surface density of the surface (6) is 0.01 kg / m 2 and 10kg / m 2 between.

12. The thermal and acoustic insulation assembly according to claim 11, characterized in that The density of the surface (6) is 20 kg / m 3 and 200kg / m 3 between.

13. The thermal and acoustic insulation assembly according to claim 11 or 12, characterized in that The thickness of the surface (6) is between 0.5 mm and 20 mm.

14. The thermal and acoustic insulation assembly according to claim 3, wherein: The air flow resistance of the micro-perforated membrane (3) is between 1 kPa.s / m and 5 kPa.s / m.

15. The thermal and acoustic insulation assembly according to claim 4, wherein: The micro-perforated membrane (3) has: - a degree of perforation between 0.05% and 2%, - Perforation radius between 0.1 and 0.25 mm.

16. The thermal and acoustic insulation assembly according to claim 4, wherein: The micro-perforated membrane (3) has: - a degree of perforation between 0.1% and 1%.

17. The thermal and acoustic insulation assembly according to claim 6, wherein: The density of the heat and sound insulation product (1) is 13 kg / m 3 and 100kg / m 3 between.

18. The thermal and acoustic insulation assembly according to claim 6, wherein: The density of the heat and sound insulation product (1) is 24 kg / m 3 and 100kg / m 3 between.

19. The thermal and acoustic insulation assembly according to claim 7, wherein: The thickness of the heat-insulating and sound-insulating product (1) is between 15 mm and 150 mm.

20. The thermal and acoustic insulation assembly according to claim 7, wherein: The thickness of the heat-insulating and sound-insulating product (1) is between 20 mm and 150 mm.

21. The thermal and acoustic insulation assembly according to claim 11, wherein: The surface density of the surface (6) is 0.1 kg / m 2 and 5kg / m 2 between.

22. The thermal and acoustic insulation assembly according to claim 12, wherein: The density of the surface (6) is 30 kg / m 3 and 150kg / m 3 between.

23. The thermal and acoustic insulation assembly according to claim 12, wherein: The density of the surface (6) is 30 kg / m 3 and 90kg / m 3 between.

24. The thermal and acoustic insulation assembly of claim 13, wherein: The thickness of the surface (6) is between 5 mm and 15 mm.

25. Use of the thermal and acoustic insulation assembly according to any one of claims 1 to 24 on a metal wall of a ship.

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