J. Phys. Colloques
Volume 51, Numéro C2, Février 1990Premier Congrès Français d'Acoustique / First French Conference on Acoustics
|Page(s)||C2-383 - C2-386|
J. Phys. Colloques 51 (1990) C2-383-C2-386
HIGH-FREQUENCY MONOSTATIC ECHOES FROM FINITE-LENGTH CYLINDERSD. BRILL1 et G.C. GAUNAURD2
1 U.S. Naval Academy, Physics Department, Annapolis, Maryland 21402, U.S.A.
2 Naval Surface Warfare Center, Research Department, (R43) white Oak, Silver Spring, Maryland 20903-5000, U.S.A.
We study the scattering of plane monochromatic acoustic waves of frequency f by rigid, finite-length cylinders of various L/D-ratios, submerged in a fluid, at arbitrary incidence angles θ. The cylinder end-caps are either flat or hemispherical. The (monostatic) backscattering cross-sections are determined by the physical optics (P.O.) or Kirchhoff method, and in some instances by saddle-point techniques. The far-field scattered pressures as functions of θ are used to obtain target strength (TS) estimates in decibels. We derive the pertinent formulas and display the resulting TS as functions of θ and f in various relevant situations. We compare results for various terminations and by various methods. The results are valid down to relatively low frequencies.