Simulation and analysis on low-frequency scattering characteristics of the finite cylindrical shell in shallow water
Low-frequency acoustic scatterings from a finite cylindrical shell are numerically analyzed by FEM. The simulation results show that the acoustic-scattering field in waveguide has lots of frequency-related sidelobes, while no sidelobes exist in free space at low frequencies. The simulation also indi...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
EDP Sciences
2019-01-01
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| Series: | MATEC Web of Conferences |
| Online Access: | https://www.matec-conferences.org/articles/matecconf/pdf/2019/32/matecconf_fcac2019_03007.pdf |
| _version_ | 1818970254372503552 |
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| author | Li Jinyu Shang Dejiang Xiao Yan |
| author_facet | Li Jinyu Shang Dejiang Xiao Yan |
| author_sort | Li Jinyu |
| collection | DOAJ |
| description | Low-frequency acoustic scatterings from a finite cylindrical shell are numerically analyzed by FEM. The simulation results show that the acoustic-scattering field in waveguide has lots of frequency-related sidelobes, while no sidelobes exist in free space at low frequencies. The simulation also indicates that the module value in waveguide can be almost 20 dB larger than that in free space at low frequency, which is caused by the ocean boundaries. We also demonstrate that when the incident wave direction is normal to the target at low frequency, the target strength will be maximum and the distribution of the acoustic-scattering field is axisymmetric about the incident waving direction. Meanwhile, the acoustic-scattering field is also related to the impedance of the seabed, and the change of the impedance makes just a little contribution to the scattering field. Finally, the influence of different target locations is analyzed, including the targets near the sea surface, seabed and the middle region of the ocean waveguide, respectively. From simulation results, it is evident that the distribution of the acoustic-scattering field at low frequency has a little difference, which is smaller than 0.5 dB with various target locations, and the change is frequency and boundary-related. |
| first_indexed | 2024-12-20T14:33:33Z |
| format | Article |
| id | doaj.art-1b6bc5f98a974f49a5adc4f8fcfd5ff4 |
| institution | Directory Open Access Journal |
| issn | 2261-236X |
| language | English |
| last_indexed | 2024-12-20T14:33:33Z |
| publishDate | 2019-01-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | MATEC Web of Conferences |
| spelling | doaj.art-1b6bc5f98a974f49a5adc4f8fcfd5ff42022-12-21T19:37:32ZengEDP SciencesMATEC Web of Conferences2261-236X2019-01-012830300710.1051/matecconf/201928303007matecconf_fcac2019_03007Simulation and analysis on low-frequency scattering characteristics of the finite cylindrical shell in shallow waterLi JinyuShang DejiangXiao YanLow-frequency acoustic scatterings from a finite cylindrical shell are numerically analyzed by FEM. The simulation results show that the acoustic-scattering field in waveguide has lots of frequency-related sidelobes, while no sidelobes exist in free space at low frequencies. The simulation also indicates that the module value in waveguide can be almost 20 dB larger than that in free space at low frequency, which is caused by the ocean boundaries. We also demonstrate that when the incident wave direction is normal to the target at low frequency, the target strength will be maximum and the distribution of the acoustic-scattering field is axisymmetric about the incident waving direction. Meanwhile, the acoustic-scattering field is also related to the impedance of the seabed, and the change of the impedance makes just a little contribution to the scattering field. Finally, the influence of different target locations is analyzed, including the targets near the sea surface, seabed and the middle region of the ocean waveguide, respectively. From simulation results, it is evident that the distribution of the acoustic-scattering field at low frequency has a little difference, which is smaller than 0.5 dB with various target locations, and the change is frequency and boundary-related.https://www.matec-conferences.org/articles/matecconf/pdf/2019/32/matecconf_fcac2019_03007.pdf |
| spellingShingle | Li Jinyu Shang Dejiang Xiao Yan Simulation and analysis on low-frequency scattering characteristics of the finite cylindrical shell in shallow water MATEC Web of Conferences |
| title | Simulation and analysis on low-frequency scattering characteristics of the finite cylindrical shell in shallow water |
| title_full | Simulation and analysis on low-frequency scattering characteristics of the finite cylindrical shell in shallow water |
| title_fullStr | Simulation and analysis on low-frequency scattering characteristics of the finite cylindrical shell in shallow water |
| title_full_unstemmed | Simulation and analysis on low-frequency scattering characteristics of the finite cylindrical shell in shallow water |
| title_short | Simulation and analysis on low-frequency scattering characteristics of the finite cylindrical shell in shallow water |
| title_sort | simulation and analysis on low frequency scattering characteristics of the finite cylindrical shell in shallow water |
| url | https://www.matec-conferences.org/articles/matecconf/pdf/2019/32/matecconf_fcac2019_03007.pdf |
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