Low- and high-frequency elastic scattering analysis of fluid-filled, flat-endcapped cylindrical shells proud on a sandy seabed

• Autorzy: Tesei A. , Groen J.
• Języki publikacji: EN

Abstrakty

EN

This work presents the analysis of at-sea scattering data by a man-made target which supports the excitation of strong structural waves or resonances, not only at low but even at high frequency (ka>100). The object is a water-filled, flat-endcapped, 2m-long, steel cylindrical shell, measured both at low frequency (2-10 kHz) and at high frequency (120 kHz), where different elastic phenomena are supported and identified. In particular, in the high-frequency sonar images obtained with an AUV-mounted synthetic aperture sonar, significant elastic effects clearly appear, which are interpreted as echoes of a shear wave travelling axially along the cylindrical shell. For interpretation of sonar images it is crucial to understand and predict these supplementary scattering mechanisms.

Słowa kluczowe

EN

sandy seabed; at-sea scattering data; hydroacoustics

• Wydawca: Polskie Towarzystwo Akustyczne. Oddział Gdański
• Czasopismo: Hydroacoustics
• Rocznik: 2008
• Tom: Vol. 11
• Strony: 388--400
• Opis fizyczny: Bibliogr. 20 poz., rys., wykr.

Twórcy

autor

Tesei A.

autor

Groen J.

• NURC,V.le S. Bartolomeo 400, 19126 La Spezia, Italy,

Bibliografia

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