Scattering of plane acoustic waves at elastic particles with rough surfaces

• Autorzy: Bjørnø L.
• Języki publikacji: EN

Abstrakty

EN

A comprehensive theoretical and numerical study oj the influence oj surface roughness oj elastic particles in water on the scattering oj ultrasonic waves has been carried out. For near spherical shape oj the particles and with small rms-roughness heights a perturbation method has been developed. In this method the first-order perturbation contribution predicts the contribution to the incoherently scattered acoustic field due to surjace roughness, and the second-order perturbation contribution predicts the change in the coherent field and will satisfy the requirement oj energy conservation. The second-order perturbation contribution is evaluated using the concept ojform function, while the first-order perturbation to the total scattered acoustic field is evaluated using the scattering cross-section. As a junction oj the ka-value and jor different rms-roughness heights a numerical study oj the jorward and backward scattering from rough, elastic particles has been carried out and a substantial roughness influence on the scattered field has been verified. Same experimental resultsfrom measurements oj scattering jrom glass and cast iron spheres have given evidence to the numerical predictions.

Słowa kluczowe

EN

ultrasonic waves; acoustic waves; rough surfaces

• Wydawca: Polskie Towarzystwo Akustyczne. Oddział Gdański
• Czasopismo: Hydroacoustics
• Rocznik: 2003
• Tom: Vol. 6
• Strony: 7--18
• Opis fizyczny: Bibliogr. 15 poz., rys.

Twórcy

autor

Bjørnø L.

• Fabriksvangen 13, DK-3550 Slangerup, Denmark

Bibliografia

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• 13. EU-funded project: SMART/ISUSAT, contract No. MAST-CT92-0082.
• 14. S. Sun, "Scattering of acoustic waves from rough interfaces between e1astic media". Ph.D. thesis. Department of Industrial Acoustics, Technica1 Universi-ty of Denmark, November 1995.
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