CN102568465A - Under-water self-adapting curved-surface composite acoustic material - Google Patents
Under-water self-adapting curved-surface composite acoustic material Download PDFInfo
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- CN102568465A CN102568465A CN2012100110676A CN201210011067A CN102568465A CN 102568465 A CN102568465 A CN 102568465A CN 2012100110676 A CN2012100110676 A CN 2012100110676A CN 201210011067 A CN201210011067 A CN 201210011067A CN 102568465 A CN102568465 A CN 102568465A
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Abstract
The invention aims at providing an under-water self-adapting curved-surface composite acoustic material, which comprises a damping layer, a self-adapting sound-insulation decoupling layer and a lower-radiation curved-surface sound-absorption layer, which are sequentially connected with one another, wherein the damping layer is a damping polymer material, the thickness of the damping layer is 10mm to 15mm, the self-adapting sound-insulation decoupling layer comprises a low-modulus polymer material of a periodic hollow cavity structure and a porous sponge material which is filled inside the periodic hollow cavity structure, the thickness of the self-adapting sound-insulation decoupling layer is 15mm to 20mm, the low-radiation curved-surface sound-absorption layer is a polymer material, and the low-radiation curved-surface sound-absorption layer is provided with through holes. By adopting of the under-water self-adapting curved-surface composite acoustic material, the under-water vibration sound radiation of the structure can be inhibited within a wide bandwidth range, and the under-water vibration sound radiation environment of a ship and an ocean engineering structure can be effectively improved.
Description
Technical field
What the present invention relates to is the acoustical material in a kind of ship machinery vibration and noise control technology field.
Background technology
The vibration under water of boats and ships and offshore engineering structure not only can influence the operate as normal of equipment; The security of harm structure; Also can produce the underwateracoustic radiation, the ambient ocean environment is formed noise pollution, and underwater sound detection, the location of Naval Architecture and Ocean Engineering structure exerted an influence in structure and surface, flow field; Particularly along with the increase of pressure; The acoustical behavior of general acoustics material will decline to a great extent, and cause boats and ships and offshore engineering structure Deep Water Acoustics barrier propterty significantly to reduce, and have a strong impact on the normal performance of boats and ships and offshore engineering structure performance.Therefore, vibration noise is significant for reducing sea noise pollution, raising boats and ships and offshore engineering structure performance under water to reduce boats and ships and ocean structure.
For reducing the vibration under water of boats and ships and offshore engineering structure; Reduce the underwateracoustic radiation of boats and ships and offshore engineering structure; The acoustic protection material has obtained developing rapidly: proposed a kind of conical cavity underwater sound absorption plate structure like Chinese patent CN200620049617.3; This structure has good sound absorbing capabilities, and the surface is comparatively smooth after installing.Chinese patent CN200920303498.3 has invented a kind of sound absorption and the sound absorption of sound insulation property and complex sound barrier that insulates against sound of having concurrently, makes it to have concurrently sound absorption and sound insulation property; But this complex structure, and be mainly used in the absorption and the isolation of air-borne sound, be not suitable for the underwater sound protection of boats and ships and offshore engineering structure.Russ P RU2138858 has introduced a kind of sound-screen under water, and by two-layer composition up and down, lower floor is made by elastomeric material; Inboard deep trouth and the boss that chadless is arranged of layer; The upper strata is by the big material of rigidity, and there is boss the inboard, and its xsect is equivalent to the section of rod; The boss on upper strata is inserted in the deep trouth of subsurface material, formed the confined air air cavity; The two-layer combination process of this structure is complicated, and practical applications has big limitation.U.S. Pat 4164727 has been introduced a kind of underwater sound sound absorption and reflection equipment, and it is formed by three layers, intermediate rubber layer band air chamber, and two-layer up and down is the metallic seal cover plate.The shortcoming of this structure is that its resistance to pressure is poor, and pressure increases will have a strong impact on its sound insulation efficient, and in addition, there is the metal shielding of rigidity in this structure, so this structure is difficult to stick in the warp architecture surface.
Summary of the invention
The object of the present invention is to provide and in the broad frequency band scope, to suppress the radiation of chatter under water of structure, effectively improve the compound acoustical material of the curved surface of self-adaptation under water of the radiation environment of chatter under water of boats and ships and offshore engineering structure.
The objective of the invention is to realize like this:
The present invention is the compound acoustical material of self-adaptation curved surface under water; It is characterized in that: comprise successively the damping layer, the self-adaptation sound insulation that link to each other decouple layer, low radiation curved surface absorbent treatment; Described damping layer is a damping polymer material; The thickness of damping layer is 10-15mm, and the described self-adaptation sound insulation layer of decoupling comprises low modulus macromolecular material with cavity structure periodically and be filled in the periodically mandruka material of cavity structure, and the decouple thickness of layer of self-adaptation sound insulation is 15-20mm; Described low radiation curved surface absorbent treatment is a macromolecular material, has through hole on the low radiation curved surface absorbent treatment.
The present invention can also comprise:
1, described damping polymer material comprises high-damping rubber, polyurethane.
2, described low modulus macromolecular material comprises soft rubber, polyurethane material, urethane rubber material, and the mandruka material comprises vulcanized rubber, polyurethane material.
3, described cavity structure is cylindrical cavity or square cavity, and the diameter of cavity, height or the length of side are 20-30mm, and the centre distance of cavity is 26-36mm.
4, described macromolecular material comprises polyurethane material, and low radiation curved surface absorbent treatment surface is two dimension or three-dimensional sinusoidal, cosine curved surface, and when wavelength was h for the λ wave height, λ was 5-8mm, and h/ λ is 1.5-2.
Advantage of the present invention is:
1, the present invention is made up of decouple layer and low radiation curved surface absorbent treatment three part-structures of damping layer, self-adaptation sound insulation, and damping layer, self-adaptation sound insulation are decoupled layer and low radiation curved surface absorbent treatment successively through the tackifier adhesion, and through the cure under pressure moulding;
Multiple noise reduction technologies such as 2, this structural design comprehensive utilization damping loss absorption, impedance mismatching, reduction radiation efficiency, the compound acoustical material of self-adaptation curved surface integrates multiple functions such as sound absorption, sound insulation and the noise reduction that shakes but make under water;
3, in the low radiation curved surface absorbent treatment of the present invention through hole is set, can ensures that self-adaptation sound insulation decouples and have identical hydrostatic force inside and outside the layer, thereby significantly improve the water pressure resistance performance of material, make material under deep-water pressure, still can keep acoustical behavior preferably;
4, the present invention is a curved surface acoustical material under water, and its absorbent treatment surface is coarse curved surface, and sound insulation and noise reducing effect is better with the plate acoustical material of weight under water for it, and applicable band is wideer;
5, material of the present invention is pasted on the safeguard structure surface through tackifier, has prevented contacting of seawater and safeguard structure, can improve the corrosion resistance and the security of safeguard structure;
6, the present invention is simple in structure, and easy construction has a good application prospect.
Description of drawings
Fig. 1 is a structural representation of the present invention;
Fig. 2 is the A-A view;
Fig. 3 is the B-B view.
Embodiment
For example the present invention is done description in more detail below in conjunction with accompanying drawing:
In conjunction with Fig. 1～3, but the object of the present invention is to provide a kind of withstand voltage, wideband sound absorption compound acoustical material of noise reduction that shakes under water, reduce the radiation of chatter under water of boats and ships and offshore engineering structure preferably, improve safeguard structure underwater sound environment.
The present invention realizes through following technical scheme, and the compound acoustical material of the said curved surface of self-adaptation under water is made up of decouple layer, low radiation curved surface absorbent treatment of damping layer, self-adaptation sound insulation.Decouple layer, low radiation curved surface absorbent treatment of damping layer, self-adaptation sound insulation is distributed in the safeguard structure outside surface successively; Damping layer, self-adaptation insulate against sound and decouple layer and hang down radiation curved surface absorbent treatment through the tackifier adhesion, and pass through the cure under pressure moulding.
Said damping layer is the damping polymer material (like materials such as high-damping rubber and polyurethane) with high resiliency and loss modulus; But damping layer thickness is confirmed by the noise reduction index of shaking of the compound acoustical material of self-adaptation curved surface under water, is generally can be controlled between 10mm～15mm; Suitably increase the surface vibration velocity that damping layer thickness can reduce safeguard structure, thereby reduce the radiation of chatter under water of safeguard structure.
The sound insulation of said self-adaptation is decoupled layer by the low modulus macromolecular material (like soft rubber, polyurethane material, urethane rubber material etc.) with cavity structure periodically and be filled in periodically that the mandruka material of cavity constitutes.Periodically cavity is through the self-adaptation sound insulation layer thickness direction of decoupling, and cavity can be cylindrical cavity or square cavity, and the cavity diameter or the length of side are generally 20mm～30mm, and the cavity center spacing is generally 26mm～36mm.Vulcanized rubber or polyurethane material that the mandruka material is lower by elastic modulus, loss characteristic is bigger constitute, and the mandruka material is filled in cylindricality or square cavity is inner.Layer thickness is confirmed by the noise reduction index of shaking of the compound acoustical material of self-adaptation curved surface under water but self-adaptation sound insulation is decoupled, and is generally 15mm～20mm.Cavity is big more, its low frequency sound insulation property better, applicable band is wideer; Sound insulating layer is thicker, and its defening effect better.
Said low radiation curved surface absorbent treatment is by having high loss characteristic, shaggy macromolecular material (like polyurethane material) and constituting through the micro through-hole of thickness direction, and its impedance is with the seawater medium is comparatively approaching on every side, so that the sound wave in the seawater around absorbing.Rough surface can make the acoustic radiation efficiency of curved surface absorbent treatment lower, and making under water, the radiation efficiency of the compound acoustical material of self-adaptation curved surface reduces.Low radiation curved surface absorbent treatment surface be two dimension or three-dimensional sine, cosine curved surface, makes under water that the radiation efficiency of the compound acoustical material of self-adaptation curved surface further reduces, and curve form is definite by the applicable band scope of the compound acoustical material of self-adaptation curved surface under water; As to establish sinusoidal wave wavelength be λ, and wave height is h, and h is generally 5mm～8mm, and h/ λ is generally 1.5～2; Increase h/ λ or h, can improve the sound absorption and the defening effect of the compound acoustical material of self-adaptation curved surface under water.Micro through-hole runs through the curved surface absorbent treatment, and it is inner to ensure that the external sea aqueous medium flows into the self-adaptation sound insulation layer of decoupling, and makes under water that the external and internal pressure of the withstand voltage acoustics compound substance of self-adaptation is consistent, and improves the withstand voltage properties of material.
The principle of work of the compound acoustical material of self-adaptation curved surface is under water:
But multiple vibration and noise reducing modes such as the integrated use damping is shaken, impedance mismatching sound insulation, loss absorption, waveform transformation, reduction radiation efficiency constitute the MULTILAYER COMPOSITE acoustical material: utilize damping vibration attenuation principle profit damping layer to be set to reduce the safeguard structure surface vibration velocity; Utilize loss sound absorption principle,, make the structure-borne sound transmission waveform transformation occur and, increase its sound absorption performance than lossy in the self-adaptation sound insulation layer set inside mandruka structure of decoupling; In conjunction with the sound radiation principle, the absorbent treatment outside surface is designed to the waveform curve form, to reduce the acoustic radiation efficiency of the compound acoustical material of self-adaptation curved surface under water, reach the effect of abundant dissipation acoustic wave energy; Based on the impedance mismatching principle, decouple layer, absorbent treatment of damping layer, self-adaptation sound insulation is designed to different impedance layers, intercept the transmission of acoustic wave energy, with effective reduction structural vibration and radiation to the external world; In the low radiation curved surface absorbent treatment through hole is set, can ensures that the material external and internal pressure is consistent, the compound acoustical material of self-adaptation curved surface still can ensure the noise reduction of shaking preferably under the deep-water pressure effect but make under water.
When the compound acoustical material of self-adaptation curved surface is applied to real ship and the protection of offshore engineering structure underwater sound, can take following mode to implement under water:
(1) the safeguard structure vibration characteristics is analyzed, confirmed that the safeguard structure sound transmission dominates pipeline, and then definite safeguard structure laying area position, size and shape.
(2) requirement of shelter of the compound acoustical material of self-adaptation curved surface (performance, withstand voltage properties and bandwidth requirement but sound absorbing capabilities, sound insulation property shake) is proposed under water.
(3) but according to the shake performance and the bandwidth requirement design damping layer of the compound acoustical material of self-adaptation curved surface under water; According to sound insulation property, withstand voltage properties and the sound insulation of bandwidth requirement design self-adaptation of the compound acoustical material of self-adaptation curved surface under water decouple layer thickness and material; Hang down radiation curved surface sound absorbing material layer, thickness and curve form parameter (seeing shown in the accompanying drawing 2) according to the sound absorbing capabilities and the bandwidth requirement design of the compound acoustical material of self-adaptation curved surface under water.When confirming under water the compound acoustics material structure of self-adaptation curved surface size, need take into full account the characteristic of vibration noise under water of safeguard structure: but shake sound insulation when having relatively high expectations like safeguard structure, can suitably increase damping layer and the self-adaptation sound insulation layer thickness 3mm～5mm that decouples; As require under water that the compound acoustical material of self-adaptation curved surface possesses good sound absorbing capabilities, then can strengthen low radiation curved surface absorbent treatment thickness 3mm～5mm.
(4) the compound acoustics material structure of the curved surface of the self-adaptation under water form of confirming according to said method; Make the mould of 0.5m * 0.5m or 0.75m * 0.75m size; And decouple layer and low radiation curved surface absorbent treatment of damping layer, self-adaptation sound insulation placed successively, adopt the moulding of tackifier cure under pressure.
(5) confirm quantity and the fixed form that acoustical material is arranged according to geometric shape, the size of laying area.To the laying area surface eliminate rust, surface preparation, adopt tackifier with the damping aspect with the surface of steel plate pressing is bonding gets final product.
Claims (9)
1. the compound acoustical material of self-adaptation curved surface under water; It is characterized in that: comprise successively the damping layer, the self-adaptation sound insulation that link to each other decouple layer, low radiation curved surface absorbent treatment; Described damping layer is a damping polymer material; The thickness of damping layer is 10-15mm, and the described self-adaptation sound insulation layer of decoupling comprises low modulus macromolecular material with cavity structure periodically and be filled in the periodically mandruka material of cavity structure, and the decouple thickness of layer of self-adaptation sound insulation is 15-20mm; Described low radiation curved surface absorbent treatment is a macromolecular material, has through hole on the low radiation curved surface absorbent treatment.
2. the compound acoustical material of the curved surface of self-adaptation under water according to claim 1, it is characterized in that: described damping polymer material comprises high-damping rubber, polyurethane.
3. the compound acoustical material of the curved surface of self-adaptation under water according to claim 1 and 2; It is characterized in that: described low modulus macromolecular material comprises soft rubber, polyurethane material, urethane rubber material, and the mandruka material comprises vulcanized rubber, polyurethane material.
4. the compound acoustical material of the curved surface of self-adaptation under water according to claim 1 and 2, it is characterized in that: described cavity structure is cylindrical cavity or square cavity, and the diameter of cavity, height or the length of side are 20-30mm, and the centre distance of cavity is 26-36mm.
5. the compound acoustical material of the curved surface of self-adaptation under water according to claim 3, it is characterized in that: described cavity structure is cylindrical cavity or square cavity, and the diameter of cavity, height or the length of side are 20-30mm, and the centre distance of cavity is 26-36mm.
6. the compound acoustical material of the curved surface of self-adaptation under water according to claim 1 and 2; It is characterized in that: described macromolecular material comprises polyurethane material; Low radiation curved surface absorbent treatment surface is two dimension or three-dimensional sinusoidal, cosine curved surface; When wavelength was h for the λ wave height, λ was 5-8mm, and h/ λ is 1.5-2.
7. the compound acoustical material of the curved surface of self-adaptation under water according to claim 3; It is characterized in that: described macromolecular material comprises polyurethane material, and low radiation curved surface absorbent treatment surface is two dimension or three-dimensional sinusoidal, cosine curved surface, when wavelength is h for the λ wave height; λ is 5-8mm, and h/ λ is 1.5-2.
8. the compound acoustical material of the curved surface of self-adaptation under water according to claim 4; It is characterized in that: described macromolecular material comprises polyurethane material, and low radiation curved surface absorbent treatment surface is two dimension or three-dimensional sinusoidal, cosine curved surface, when wavelength is h for the λ wave height; λ is 5-8mm, and h/ λ is 1.5-2.
9. the compound acoustical material of the curved surface of self-adaptation under water according to claim 5; It is characterized in that: described macromolecular material comprises polyurethane material, and low radiation curved surface absorbent treatment surface is two dimension or three-dimensional sinusoidal, cosine curved surface, when wavelength is h for the λ wave height; λ is 5-8mm, and h/ λ is 1.5-2.
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Cited By (8)
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| CN104464714A (en) * | 2014-11-05 | 2015-03-25 | 大连理工大学 | Three-dimensional sound invisible cloak structure |
| CN107263967A (en) * | 2017-07-20 | 2017-10-20 | 北京海月星科技有限公司 | One kind sound insulation isolator and preparation method and application |
| CN110580895A (en) * | 2019-09-24 | 2019-12-17 | 哈尔滨工程大学 | sound baffle combination for underwater detection equipment |
| CN112164383A (en) * | 2020-09-07 | 2021-01-01 | 南京航空航天大学 | Underwater sound absorption structure with sine partition board filled with viscoelastic material |
| CN112289294A (en) * | 2020-09-07 | 2021-01-29 | 南京航空航天大学 | Underwater sound absorption structure with fish scale-shaped partition board filled with viscoelastic material |
| CN113380219A (en) * | 2021-06-07 | 2021-09-10 | 哈尔滨工程大学 | Bendable and foldable air interlayer type flexible sound reflection structure and application thereof |
| CN113536055A (en) * | 2021-07-16 | 2021-10-22 | 三一重机有限公司 | Method for determining acoustic material on construction machine |
| CN114242026A (en) * | 2021-11-04 | 2022-03-25 | 中国船舶重工集团公司第七二五研究所 | Low-frequency pressure-resistant underwater sound insulation acoustic structure |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104464714A (en) * | 2014-11-05 | 2015-03-25 | 大连理工大学 | Three-dimensional sound invisible cloak structure |
| CN104464714B (en) * | 2014-11-05 | 2017-06-23 | 大连理工大学 | A kind of three-dimensional Sound stealth cape structure |
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| CN107263967B (en) * | 2017-07-20 | 2019-07-16 | 北京海月星科技有限公司 | A kind of sound insulation isolator and the preparation method and application thereof |
| CN110580895A (en) * | 2019-09-24 | 2019-12-17 | 哈尔滨工程大学 | sound baffle combination for underwater detection equipment |
| CN112289294A (en) * | 2020-09-07 | 2021-01-29 | 南京航空航天大学 | Underwater sound absorption structure with fish scale-shaped partition board filled with viscoelastic material |
| CN112164383A (en) * | 2020-09-07 | 2021-01-01 | 南京航空航天大学 | Underwater sound absorption structure with sine partition board filled with viscoelastic material |
| CN112164383B (en) * | 2020-09-07 | 2023-07-25 | 南京航空航天大学 | Underwater sound absorption structure with sine partition plate filled with viscoelastic material |
| CN113380219A (en) * | 2021-06-07 | 2021-09-10 | 哈尔滨工程大学 | Bendable and foldable air interlayer type flexible sound reflection structure and application thereof |
| CN113380219B (en) * | 2021-06-07 | 2022-05-20 | 哈尔滨工程大学 | Bendable and foldable air interlayer type flexible sound reflection structure and application thereof |
| CN113536055A (en) * | 2021-07-16 | 2021-10-22 | 三一重机有限公司 | Method for determining acoustic material on construction machine |
| CN114242026A (en) * | 2021-11-04 | 2022-03-25 | 中国船舶重工集团公司第七二五研究所 | Low-frequency pressure-resistant underwater sound insulation acoustic structure |
| CN114242026B (en) * | 2021-11-04 | 2024-05-28 | 中国船舶重工集团公司第七二五研究所 | Low-frequency pressure-resistant underwater sound insulation acoustic structure |
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Application publication date: 20120711 |