Underwater unmanned vehicle carbon fiber matrix glue-embedded sound transmission structure and manufacturing method thereof

Abstract

The invention provides an underwater unmanned vehicle carbon fiber matrix glue-embedded sound transmission structure and a manufacturing method, and belongs to the technical field of underwater unmanned vehicle carrier structures, the underwater unmanned vehicle carbon fiber matrix glue-embedded sound transmission structure comprises a body shell plate, N embedding holes are formed in the body shell plate, the body shell plate is located on an underwater unmanned vehicle carrier, a sound transmission glue layer is arranged in each embedding hole, and N is an integer greater than or equal to 2; the body shell plate collects all sound production loads into an envelope surface of the unmanned underwater vehicle. According to the invention, the glue solution forms the sound transmission glue layer through a hanging glue bonding process, and the sound transmission glue layer is embedded into the embedded hole reserved in the body shell, so that an integral sound transmission structure is finally formed. The carbon fiber matrix glue-embedded sound transmission structure provided by the invention provides a high-sound-transmission carrying environment for a sound production load and performs omnidirectional protection on the sound production load, and meanwhile, the structure as a part of a carrier structure of the underwater unmanned vehicle meets the strength requirement, does not exceed an envelope surface of the underwater unmanned vehicle, and does not affect the overall water resistance and navigation noise.

Description

Technical Field

[0001] This invention belongs to the technical field of underwater unmanned vehicle carrier structure, specifically relating to a carbon fiber matrix embedded acoustic transparent structure for underwater unmanned vehicles and its manufacturing method. Background Technology

[0002] As the demands for marine resource surveying, marine ecological environment monitoring, and marine condition collection become more complex and specialized, the payloads carried by underwater unmanned vehicle platforms are becoming more specialized and sophisticated, thus placing increasingly higher environmental requirements on these payloads.

[0003] For example, some detection payloads place higher demands on the acoustic transmission performance of underwater unmanned vehicle carrier structures, which requires the optimized design of underwater unmanned vehicle carrier structures under the dual consideration of structural performance and acoustic transmission performance.

[0004] Currently, most solutions to the high sound transmission requirement involve protruding the load array into the underwater unmanned vehicle's envelope, adding a fairing with sound-transmitting material to the sound-transmitting area, or opening sound-transmitting holes in the vehicle's envelope. However, these methods all have some drawbacks, such as increased water resistance due to the load protruding into the vehicle's envelope, ineffective load protection, excessive openings in the vehicle's envelope leading to high noise, and excessive weakening of the vehicle platform's structural strength. If the payload size is too large, these drawbacks become particularly prominent and cannot be ignored.

[0005] Faced with the demands of large-scale, heavy detection payloads on the structure of underwater unmanned vehicles (UAVs), requiring high capacity, high strength, and high acoustic transmission, the traditional metal carrier structure has been abandoned in favor of carbon fiber composite materials, known for their high strength and lightweight, while also considering the impact of carbon fiber composites on acoustic performance. The mechanical and acoustic properties of carbon fiber composites are anisotropic, with higher sound velocity along the fiber direction and lower velocity perpendicular to it, leading to a more complex sound wave propagation path and more complex acoustic characteristics. In the underwater environment, the transmission efficiency of sound waves at the water-carbon fiber composite interface is significantly affected by factors such as the density, elastic modulus, and structure of the carbon fiber composite material.

[0006] First, the sound velocity of carbon fiber composites is related to their elastic modulus and density. Carbon fiber has a high elastic modulus and a low density, so its sound velocity is generally higher than that of water. The propagation speed and attenuation coefficient of sound waves differ in different media, leading to more complex refraction and reflection at the water-carbon fiber composite interface. Second, the acoustic impedance of carbon fiber composites differs significantly from that of water. This difference in acoustic impedance affects the ratio of reflection to transmission when sound waves enter the carbon fiber shell from water. Water has a lower acoustic impedance while carbon fiber has a higher acoustic impedance, resulting in enhanced reflection at the shell interface and reduced transmittance. Third, carbon fiber… The viscoelasticity and interlayer structure of carbon fiber can lead to energy dissipation during sound wave propagation. Manufacturing defects (such as pores and delamination) can cause sound wave scattering and multiple reflections, affecting acoustic performance and reducing the transmission efficiency of sound waves in underwater environments. In addition, the frequency of sound waves is also a factor. When the wavelength of sound waves is close to the thickness of the carbon fiber composite shell, the resonance effect can lead to nonlinear changes in reflection or transmission. High-frequency sound waves are more easily attenuated by carbon fiber composites. Therefore, the effect of carbon fiber shell structures of the same thickness on the attenuation of sound waves of different frequencies is more evident in the case where the degree of attenuation is greater for high-frequency sound waves than for low-frequency sound waves. Summary of the Invention

[0007] The purpose of this invention is to provide a carbon fiber matrix embedded acoustic transparent structure for underwater unmanned vehicles and its manufacturing method, which solves the problem of carrying ultra-large-sized loads with high acoustic transparency requirements in existing underwater unmanned vehicles, and protects the strength, water resistance and noise of the carrier.

[0008] The objective of this invention is achieved through the following technical solution:

[0009] A carbon fiber matrix embedded acoustic structure for an underwater unmanned vehicle includes: a main shell plate with N embedding holes, the main shell plate being located on the underwater unmanned vehicle carrier, and an acoustically transparent adhesive layer being provided in the embedding holes, wherein the main shell plate contains all the sound-emitting load within the envelope of the underwater unmanned vehicle.

[0010] Furthermore, the main body shell plate is a detachable shell plate structure of the outer envelope surface of the underwater unmanned vehicle carrier.

[0011] Furthermore, the sound-permeable adhesive layer is bonded to the sound-generating load transducer array surface with the pre-reserved embedding hole on the main body shell plate and then cured to form an integral sound-permeable structure.

[0012] Furthermore, the main body shell plate is a carbon fiber shell plate.

[0013] The present invention may also include:

[0014] A method for manufacturing the above-mentioned carbon fiber matrix embedded acoustic transparent structure for underwater unmanned vehicles, the method comprising the following steps:

[0015] Step 1: Secure the embedded hole spacer blocks to the envelope surface of the male mold of the main body shell plate on the steel platform according to the distribution spacing of the embedded holes, and carry out mold surface treatment, release cloth laying and resin channel laying preparation work.

[0016] Step 2: Gradually lay the carbon fiber cloth layer onto the surface of the pre-treated demolding cloth layer of the male mold of the main body shell plate on the steel platform, and then perform the mold closing operation of the male and female molds of the main body shell plate.

[0017] Step 3: Conduct an airtightness check after mold closing according to the airtightness process design requirements;

[0018] Step 4: Perform resin flow guiding work on the main body shell plate according to the shell plate molding resin flow guiding process design requirements, and perform the main body shell plate molding and curing work according to the shell plate curing and molding process design requirements.

[0019] Step 5: Demold the embedded hole spacer block of the solidified body shell plate and perform surface treatment around the embedded hole.

[0020] Step 6: Apply adhesive to the embedded hole gradually and repeatedly until the adhesive layer thickness required by the adhesive bonding process design is reached, and then install the sound-permeable adhesive layer limiting block above the sound-permeable adhesive layer.

[0021] Step 7: Perform post-curing work on the body shell plate 1 after adhesive bonding according to the post-curing process design requirements of the carbon fiber matrix embedded acoustic structure.

[0022] Step 8: Demolding the post-cured carbon fiber matrix embedded acoustic structure from the female mold and the male mold of the main shell plate, and performing surface treatment on the carbon fiber matrix embedded acoustic structure.

[0023] The beneficial effects of this invention are as follows:

[0024] This invention provides a better solution for the load-bearing environment requirements of high sound transmission loads, especially for large-sized sound-bearing loads, providing a more ideal load-bearing environment; the carbon fiber matrix embedded sound-transmitting structure can contain the entire load within the envelope of the underwater unmanned vehicle, providing all-round protection for the load without affecting the hydrodynamic data of the underwater unmanned vehicle itself.

[0025] The carbon fiber matrix embedded acoustically transparent structure of this invention provides a highly transparent mounting environment for the acoustic load and offers omnidirectional protection for the acoustic load 3. Simultaneously, as part of the underwater unmanned vehicle (UAV) carrier structure, this structure meets its strength requirements, does not exceed the UAV's envelope, and does not affect overall water resistance or navigation noise. This invention provides an ideal solution for the high-performance mounting environment requirements of underwater UAVs carrying acoustic loads, effectively integrating optimal acoustic performance of the acoustic load with the UAV carrier structure. Attached Figure Description

[0026] Appendix Figure 1 This is a schematic diagram of the structure of the present invention;

[0027] Appendix Figure 2 This is a schematic diagram of the manufacturing process of the present invention. Figure 1 ;

[0028] Appendix Figure 3 This is a schematic diagram of the manufacturing process of the present invention. Figure 2 ;

[0029] Appendix Figure 4 This is a cross-sectional view of the manufacturing process of the present invention. Figure 1 ;

[0030] Appendix Figure 5 It is attached Figure 4 A magnified view of part A in the image;

[0031] Appendix Figure 6 This is a cross-sectional view of the manufacturing process of the present invention. Figure 2 ;

[0032] Appendix Figure 7 It is attached Figure 6 A magnified view of part B in the image;

[0033] Appendix Figure 8 This is a schematic diagram of the manufacturing process of the present invention. Figure 3 .

[0034] In the attached diagram: 1. Main body shell plate; 2. Sound-permeable adhesive layer; 3. Sound-generating load; 4. Male mold of main body shell plate; 5. Carbon fiber cloth layer; 6. Embedded hole occupant block; 7. Female mold of main body shell plate; 8. Embedded hole; 9. Sound-permeable adhesive layer limiting block. Detailed Implementation

[0035] The present invention will now be further described with reference to the accompanying drawings.

[0036] This invention provides a carbon fiber matrix intercalated acoustically transparent structure for underwater unmanned vehicles (UUVs), as shown in the attached figure. Figure 1As shown, it includes: a main shell plate 1, which has N embedding holes 8. The main shell plate 1 is located on the underwater unmanned vehicle carrier. The embedding holes 8 have a sound-permeable adhesive layer 2. The main shell plate 1 contains all the sound-emitting load 3 within the envelope of the underwater unmanned vehicle.

[0037] The main body shell plate 1 is a carbon fiber shell plate.

[0038] In this embodiment, the sound-permeable adhesive layer 2 is bonded to the sound-generating load transducer array surface with the pre-reserved embedding hole on the main body shell plate and then cured to form an integral sound-permeable structure.

[0039] The main body shell plate 1 is a detachable shell plate structure for the outer envelope of the underwater unmanned vehicle carrier.

[0040] The main body shell 1 is part of the underwater unmanned vehicle carrier structure and undertakes the functions of carrier strength support, underwater navigation guidance, and noise reduction.

[0041] The main body shell 1 provides a mounting environment and protection for the acoustic payload 3 carried by the underwater unmanned vehicle.

[0042] The embedded hole 8 on the main shell plate 1 provides a sound information transmission channel for the sound-generating load 3, and the shape of the embedded hole 8 can be circular, square, or other shapes that meet the requirements of the transmission channel.

[0043] The sound-permeable adhesive layer 2 embedded on the main shell plate 1 provides a medium for transmitting sound information for the sound-generating load 3. The material of the sound-permeable adhesive layer 2 can be the same material as the transducer array surface of the sound-generating load 3, or it can be other materials that meet the sound transmission requirements.

[0044] The sound-permeable adhesive layer 2 and the embedded hole 8 reserved on the main body shell plate 1 can be embedded by adhesive bonding process, or by screwing, riveting, gluing and other processes.

[0045] The carbon fiber matrix intercalated acoustic structure of the present invention is still a carbon fiber composite material, which has little impact on its own structural strength and meets the structural strength requirements of the underwater unmanned vehicle carrier. The carbon fiber matrix intercalated acoustic structure is a shell structure that is sound-permeable and water-impermeable, which meets the load sound transmission requirements without increasing the overall weight of the underwater unmanned vehicle carrier structure or affecting the noise index of the underwater unmanned vehicle during navigation.

[0046] This embodiment also includes:

[0047] A method for manufacturing the above-mentioned carbon fiber matrix embedded acoustic transparent structure for underwater unmanned vehicles, characterized in that the method includes the following steps:

[0048] Step 1: As Figure 2 ,4 As shown in Figure 5, the embedded hole occupant block 6 is fastened to the envelope surface of the male mold 4 of the main body shell plate on the steel platform according to the distribution spacing of the embedded holes 8, and the mold surface treatment, release cloth laying and resin adhesive channel laying preparation work are carried out according to the pre-process design requirements of carbon fiber shell plate molding layup.

[0049] Step 2: As Figure 2 , 3 As shown, the carbon fiber cloth layer 5 is laid step by step onto the surface of the pre-treated demolding cloth layer of the male mold 4 of the main body shell plate on the steel platform according to the layup process design requirements. Then, the male mold and female mold 7 of the main body shell plate are joined together according to the mold closing process design requirements.

[0050] Step 3: Conduct an airtightness check after mold closing according to the airtightness process design requirements;

[0051] Step 4: Perform resin flow guiding work on the main body shell plate 1 according to the shell plate molding resin flow guiding process design requirements, and perform molding and curing work on the main body shell plate 1 according to the shell plate curing molding process design requirements.

[0052] Step 5: Demold the embedded hole occupant block 6 according to the demolding process design requirements of the solidified body shell plate 1, and perform surface treatment around the embedded hole 8.

[0053] Step 6: As Figure 4-7 As shown, the embedded hole 8 is gradually and repeatedly coated with adhesive according to the design requirements of the in-hole adhesive bonding process until the adhesive layer thickness required by the adhesive bonding process design is reached, and the sound-permeable adhesive layer limiting block 9 is installed above the sound-permeable adhesive layer 2.

[0054] Step 7: Perform post-curing work on the body shell plate 1 after adhesive bonding according to the post-curing process design requirements of the carbon fiber matrix embedded acoustic structure.

[0055] Step 8: As Figure 6-7 As shown, the carbon fiber matrix embedded acoustic structure after post-curing is demolded according to the demolding process design requirements of the main shell plate, and the female mold 7 and male mold 4 of the main shell plate are demolded. The carbon fiber matrix embedded acoustic structure is then surface-treated.

[0056] The carbon fiber matrix embedded acoustically transparent structure of the present invention meets the environmental requirements for carrying large-size, high-sound-transparency payloads on underwater unmanned vehicles, as well as the strength requirements of the underwater unmanned vehicle carrier structure itself, as specifically demonstrated below:

[0057] 1. It can meet the environmental requirements for carrying large-sized, high-sound-transmission payloads on underwater unmanned vehicles;

[0058] 2. It can meet the requirements of reducing water resistance and improving load protection by ensuring that the payload is located within the envelope of the underwater unmanned vehicle;

[0059] 3. It can meet the requirements of load sound transmission without weakening the structural strength of the aircraft carrier itself;

[0060] 4. It can meet the design requirement of having no openings in the sound-transmitting parts of the aircraft's envelope surface, which means that it can transmit sound, block water, and does not affect the navigation noise index.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A carbon fiber matrix intercalated acoustically transparent structure for underwater unmanned vehicles, characterized in that, include: The main body shell plate (1) has N embedding holes (8) on it. The main body shell plate (1) is located on the underwater unmanned vehicle carrier. The embedding holes (8) have a sound-permeable adhesive layer (2). The main body shell plate (1) contains all the sound-emitting load (3) within the envelope of the underwater unmanned vehicle.

2. The carbon fiber matrix embedded acoustic structure for underwater unmanned vehicles according to claim 1, characterized in that, The main body shell plate (1) is a detachable shell plate structure of the outer envelope surface of the underwater unmanned vehicle carrier.

3. The carbon fiber matrix embedded acoustic structure for underwater unmanned vehicles according to claim 1 or 2, characterized in that, The sound-permeable adhesive layer (2) is bonded to the sound-generating load transducer array surface with the embedded hole reserved on the main body shell plate and then cured to form an integral sound-permeable structure.

4. The carbon fiber matrix intercalated acoustic structure for underwater unmanned vehicles according to claim 3, characterized in that, The main body shell plate (1) is a carbon fiber shell plate.

5. A method for manufacturing a carbon fiber matrix intercalated acoustically transparent structure for an underwater unmanned vehicle according to any one of claims 1-4, characterized in that, The method includes the following steps: Step 1: Secure the embedded hole occupant block (6) to the envelope surface of the male mold (4) of the main body shell plate on the steel platform according to the distribution spacing of the embedded holes (8), and carry out mold surface treatment, release cloth laying and resin liquid channel laying preparation work. Step 2: Gradually lay the carbon fiber cloth layer (5) onto the surface of the pre-treated demolding cloth layer of the male mold (4) of the main body shell plate on the steel platform, and then perform the mold closing work of the male mold and female mold of the main body shell plate (7). Step 3: Conduct an airtightness check after mold closing according to the airtightness process design requirements; Step 4: Perform resin flow guiding work on the main body shell plate (1) according to the shell plate molding resin flow guiding process design requirements, and perform molding and curing work on the main body shell plate (1) according to the shell plate curing molding process design requirements. Step 5: Demold the solidified body shell plate (1) with the embedded hole occupant block (6) and perform surface treatment around the embedded hole (8); Step 6: Gradually and repeatedly apply adhesive to the embedded hole (8) until the adhesive layer thickness required by the adhesive bonding process design is reached, and install the sound-permeable adhesive layer limiting block (9) above the sound-permeable adhesive layer (2); Step 7: Perform post-curing work on the body shell plate (1) after adhesive bonding according to the post-curing process design requirements of the carbon fiber matrix embedded acoustic structure. Step 8: Demolding the carbon fiber matrix embedded acoustic structure after post-curing from the body shell female mold (7) and the body shell male mold (4), and performing surface treatment on the carbon fiber matrix embedded acoustic structure.

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