CN116477028A - Local small-curvature-radius airfoil structure for underwater vehicle - Google Patents
Local small-curvature-radius airfoil structure for underwater vehicle Download PDFInfo
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- CN116477028A CN116477028A CN202310462819.9A CN202310462819A CN116477028A CN 116477028 A CN116477028 A CN 116477028A CN 202310462819 A CN202310462819 A CN 202310462819A CN 116477028 A CN116477028 A CN 116477028A
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- underwater vehicle
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- radius
- shielding structure
- curvature
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- 239000000463 material Substances 0.000 claims abstract description 22
- 229920002635 polyurethane Polymers 0.000 claims abstract description 16
- 239000004814 polyurethane Substances 0.000 claims abstract description 16
- 239000010410 layer Substances 0.000 claims description 9
- 239000002356 single layer Substances 0.000 claims description 4
- 238000010521 absorption reaction Methods 0.000 abstract description 6
- 230000000694 effects Effects 0.000 abstract description 6
- 238000000034 method Methods 0.000 abstract description 6
- 238000005265 energy consumption Methods 0.000 abstract description 2
- 238000001514 detection method Methods 0.000 description 4
- 238000013461 design Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000011358 absorbing material Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 238000012938 design process Methods 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 239000010432 diamond Substances 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
- B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
- B63G8/14—Control of attitude or depth
- B63G8/20—Steering equipment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63C—LAUNCHING, HAULING-OUT, OR DRY-DOCKING OF VESSELS; LIFE-SAVING IN WATER; EQUIPMENT FOR DWELLING OR WORKING UNDER WATER; MEANS FOR SALVAGING OR SEARCHING FOR UNDERWATER OBJECTS
- B63C11/00—Equipment for dwelling or working underwater; Means for searching for underwater objects
- B63C11/52—Tools specially adapted for working underwater, not otherwise provided for
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
- B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T70/00—Maritime or waterways transport
- Y02T70/10—Measures concerning design or construction of watercraft hulls
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Aviation & Aerospace Engineering (AREA)
- Ocean & Marine Engineering (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
The local small-curvature-radius airfoil structure comprises a front edge small-radius semi-cylindrical structure, a resonant cavity and a rear edge shielding structure, wherein the front edge small-radius semi-cylindrical structure is tightly connected with the rear edge shielding structure, and a plurality of identical truncated cone-shaped resonant cavities are embedded in the outer side of the rear edge shielding structure at equal intervals. The invention reduces the target strength in the transverse direction or even in the whole space by locally improving the appearance without changing the appearance and the structure of the original underwater vehicle, and the externally added airfoil structure can be quickly disassembled and is easy to pour and form according to a certain line type and easy to process. The resonant cavity can improve the low-frequency sound absorption effect of the structure through resonance, and the layered polyurethane material can increase energy consumption and reduce reflection. The device can be designed with a target body at the same time in the future, is combined with a control surface (rudder; wing), improves stealth performance while improving control capability, and provides engineering application value for controlling the target strength of the underwater vehicle.
Description
Technical Field
The invention belongs to the technical field of underwater target sound stealth, and particularly relates to a local small-curvature-radius airfoil structure for an underwater vehicle.
Background
The target intensity TS (Target Strength) is a measure of the target's ability to reflect sound, and is closely related to the active detection band, the target's shape and internal structure, the detection angle, the sonar detection mode, etc. The target strength of the underwater equipment determines the detection performance of the active sonar, and is directly related to the stealth capability of the underwater target to the active sonar, so that the design with low target strength becomes an indispensable content in the underwater target sound stealth design in the future. In recent years, research on theoretical prediction, evaluation and test of target intensity has been paid attention to. Therefore, effective reduction of geometric echo (rigid echo) is a key to reducing underwater target strength and improving sound concealment performance. For research on changing the target line type, foreign countries have been involved, and us nosrop-lattice Lu Man company has proposed a new concept submarine model, and domestic middle ship 702 has also reported a new concept submarine or submarine.
There are two approaches to underwater vehicle target strength control, namely acoustic cladding and contour/structural design techniques. The underwater acoustic coating is used as an effective stealth means, can inhibit noise vibration, reduce the target strength of the underwater vehicle, and improve the concealment of the vehicle, and is widely used by naval countries in the world. A great deal of researches show that the effect of laying sound absorption materials on reducing the target strength of a complex target is not obvious at present at low frequency; and as the frequency increases, the effect of the sound absorbing material becomes more and more pronounced. Changing the shape of an underwater vehicle can also effectively reduce the target strength of the vehicle, and has been widely used in the design process of new-concept submarines.
Disclosure of Invention
The invention aims to improve the sound stealth performance of an underwater vehicle and reduce the sound target strength of the underwater vehicle.
In order to achieve the above purpose, the invention is realized by adopting the following technical scheme.
A local small radius of curvature airfoil structure for an underwater vehicle, comprising:
the front edge semi-cylinder structure is a hollow semi-cylinder;
the rear edge shielding structure comprises a hollow trapezoid shell with a small front end and a large rear end, and a volume scaling ratio which is 1, wherein the shape of the hollow trapezoid shell is the same as that of the shell: n is formed by a multi-layer arc structure;
the resonant cavity is a truncated cone-shaped air cavity;
the front end of the rear edge shielding structure is connected with the front edge semi-cylindrical structure, and the end face of the rear end is arc-shaped and is used for being attached to the main body of the underwater vehicle; a plurality of resonant cavities are embedded in the front end face of the inner first layer of arc-shaped structure of the trailing edge shielding structure at equal intervals.
Preferably, the height H of the leading edge semi-cylindrical structure is the same as the shell height H of the trailing edge shielding structure; bottom radius R of the leading edge semi-cylindrical structure 1 The distance between the trailing edge shielding structure and the leading edge semi-cylindrical structure is 2R 1 。
The total length of the trailing edge shielding structure is D.
Preferably, the front edge semi-cylindrical structure is made of a single-layer polyurethane material, the rear edge shielding structure is made of a layered medium polyurethane material, and the shell is made of the same polyurethane material as the front edge semi-cylindrical structure.
Compared with the prior art, the invention has the beneficial effects that:
1) On the premise of not changing the appearance and the structure of the original underwater vehicle, the target strength in the normal transverse direction and even in the whole space is reduced by locally improving the appearance, the existence of the resonant cavity can enhance the low-frequency sound absorption performance of the structure, and the energy loss and the sound velocity difference are formed by using layered polyurethane materials, so that sound waves entering the structure deflect towards two sides of the structure and even leave the wing-shaped structure, and the reflection of the underwater vehicle is reduced.
2) The externally-mounted structure can be quickly disassembled, so that the cost of integrally laying an acoustic coating is avoided, and the structure can be designed with a target body at the same time in the future, and can be combined with a control surface (rudder; wings) are combined to improve stealth performance while improving control capability.
Drawings
FIG. 1 is a schematic view of a local small radius of curvature airfoil configuration for an underwater vehicle of the present invention;
FIG. 2 is a schematic representation of a model of a local small radius of curvature airfoil structure for an underwater vehicle of the present invention, wherein (a) is a simulated view and (b) is a cross-sectional view of (a);
fig. 3 is a state diagram of the use of the present invention for a local small radius of curvature airfoil structure for an underwater vehicle.
Detailed Description
The invention will be further described with reference to the drawings and examples, which should not be construed as limiting the scope of the invention.
Referring to fig. 1, fig. 1 is a schematic view of a local small radius of curvature airfoil structure for an underwater vehicle according to the present invention, and as shown, a local small radius of curvature airfoil structure for an underwater vehicle includes a leading edge semi-cylindrical structure 1, a resonant cavity 2, and a trailing edge shielding structure 3. The front edge semi-cylindrical structure 1 is tightly connected with the rear edge shielding structure 3, and a plurality of identical truncated cone-shaped resonant cavities 2 are embedded at equal intervals on the outer side of the rear edge shielding structure 3. The leading-edge semi-cylindrical structure 1 is made of a single layer of polyurethane material and is shaped with a radius R of the bottom surface 1 Semi-cylinders with height H. The resonant cavity 2 is an air cavity and is shaped as an upper bottom surface with radius r 1 The radius of the lower bottom surface is r 2 Round platform with height L. The trailing edge shielding structure 3 is made of layered medium polyurethane material, wherein the outermost polyurethane material and the leading edge small radius semicircle structure 1 are made of the same material. The shape of the device is an arc-shaped structure, the front end of which is closely connected with the semi-cylindrical structure with the small radius of the front edge, and the rear end of which is connected with the main body part of the underwater vehicle. High as H and front end length of 2R 1 The open angle at the rear end is phi, the radius of the main body part of the underwater vehicle is R, and the integral length of the rear edge shielding structure is D. The inside is a multi-layer arc structure which has the same shape as the shell and has the volume scaling ratio of 1:N, and the back end opening angle is phi N 。
The cross section of the underwater vehicle is changed from a round shape to an oval shape or even a diamond shape, and the curvature radius is reduced by additionally installing external components. I.e. by reducing its major radius of curvature.
Referring to fig. 2, fig. 2 is a schematic diagram of a simple model of a local airfoil with small radius of curvature according to the present invention, as in fig. 2 (a), a simple cylinder is used to verify the feasibility of the scheme of the present invention, the middle is a large cylinder formed by approximating the main body of an underwater vehicle, the height is h=10m, the resonant cavity is an air cavity, and the radius of the upper bottom surface is r 1 =0.14m, radius of lower floor r 2 =0.45 m, high l=0.6 m. Wherein the material of the front edge small radius semi-cylindrical structure is a single layer polyurethane material (density p=1150 kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the Poisson ratio nu=0.45; young's modulus e=30 MPa), the internal layered structure is made of layered polyurethane material (the parameters of the materials used for the semi-cylinder with small radius of the outermost layer and the front edge are the same; the second layer material parameters are as follows: density ρ=1200 kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the Poisson ratio nu=0.42; young's modulus e=39.4 MPa; the innermost layer material parameters are: density ρ=1250 kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the Poisson ratio nu=0.4; young's modulus e=53 MPa). Fig. 2 (b) is a cross-sectional view of fig. 2 (a) with a large cylinder radius r=3.5m, a height h=10m, a span d=5r=17.5m, and a leading edge semi-cylinder radius R 1 =0.875 m, h=10m high. The wing section is in plane expansion, the section is in a plurality of arcs, the head part is in a semi-cylinder shape, the end part is conformal with the large cylinder, the scaling ratio of the wing section and the outer layer is 1:1.25 and 1:1.67 respectively, the end part is conformal with the large cylinder, the trailing edge opening angles are phi=45°, phi respectively 2 =35° and Φ 3 =25°, as shown in fig. 2 (b).
Aiming at the relation between the strength and the radius of a cylindrical target, the invention can be hung on the wing-shaped structure on the side surface of the cylinder, the rear edge of the wing is utilized to shield the half-wave node which mainly acts on the cylinder to scatter the cylinder, and meanwhile, the small radius structure of the front edge of the wing can reduce the strength of the target.
FIG. 3 is a state diagram of the use of the local small radius of curvature airfoil structure of the invention. The middle cylinder is a main body structure similar to an underwater vehicle, the wing-shaped structure is tightly connected to the main body part of the underwater vehicle through an external steel member, and the wing-shaped structure and the main body part are not rigidly connected in a welding mode, so that the wing-shaped structure can be detached easily. The two-sided airfoil structure is the structure depicted in fig. 1.
Through the test surface, the invention adopts polyurethane material, and has certain sound absorption effect; the components can be quickly disassembled and assembled; the existence of the resonant cavity enhances the low-frequency sound absorption effect, and the layered polyurethane material bends sound rays and even deviates from the wing-shaped structure, so that reflection is reduced. On the premise of not changing the appearance and the structure of the original underwater vehicle, the target strength in the transverse direction or even in the whole space is reduced by locally improving the appearance, and the externally-added airfoil structure can be quickly disassembled and is easy to pour and mold according to a certain line type and easy to process. The resonant cavity can improve the low-frequency sound absorption effect of the structure through resonance, and the layered polyurethane material can increase energy consumption and reduce reflection. The device can be designed with a target body at the same time in the future, is combined with a control surface (rudder; wing), improves stealth performance while improving control capability, and provides engineering application value for controlling the target strength of the underwater vehicle.
Claims (4)
1. A local small radius of curvature airfoil structure for an underwater vehicle, comprising:
the front edge semi-cylindrical structure (1) is a hollow semi-cylinder;
the rear edge shielding structure (3) is formed by a hollow trapezoid shell with a small front end and a large rear end, and a volume scaling ratio which is the same as the shell in shape and is 1: n is formed by a multi-layer arc structure;
the resonant cavity (2) is a truncated cone-shaped air cavity;
the front end of the rear edge shielding structure (3) is connected with the front edge semi-cylindrical structure (1), and the end face of the rear end is arc-shaped and is used for being attached to the main body of the underwater vehicle; a plurality of resonant cavities (2) are embedded in the front end face of the inner first layer of arc-shaped structure of the rear edge shielding structure (3) at equal intervals.
2. The local small radius of curvature airfoil structure for an underwater vehicle according to claim 1, characterized in that the height H of said leading edge semi-cylindrical structure (1) is the same as the envelope height H of said trailing edge shielding structure (3); the front edge semi-cylindrical junctionBottom radius R of structure (1) 1 The distance between the trailing edge shielding structure (3) and the leading edge semi-cylindrical structure (1) is 2R 1 。
3. Local small radius of curvature airfoil structure for an underwater vehicle according to claim 2, characterized in that the trailing edge shielding structure (3) has an overall length D.
4. The local small radius of curvature airfoil structure for an underwater vehicle according to claim 1, characterized in that said leading edge semi-cylindrical structure (1) is made of a single layer of polyurethane material, said trailing edge shielding structure (3) is made of a layered medium polyurethane material, and the outer shell is made of the same polyurethane material as said leading edge semi-cylindrical structure (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310462819.9A CN116477028B (en) | 2023-04-26 | Local small-curvature-radius airfoil structure for underwater vehicle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310462819.9A CN116477028B (en) | 2023-04-26 | Local small-curvature-radius airfoil structure for underwater vehicle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116477028A true CN116477028A (en) | 2023-07-25 |
| CN116477028B CN116477028B (en) | 2024-07-05 |
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| CN115798443A (en) * | 2022-11-29 | 2023-03-14 | 江苏科技大学 | Pressure-resistant broadband silencing tile filled with sound absorption material |
| CN115910016A (en) * | 2022-12-02 | 2023-04-04 | 浙江大学 | Underwater sound absorption covering layer based on cavity resonance |
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