ASA 130th Meeting - St. Louis, MO - 1995 Nov 27 .. Dec 01
2aUW13. Method of determining the effective scattering cross section.
Alexander E. Ekimov
Andrey V. Lebedev
Hydroacoustic Div., Inst. Appl. Phys., Russian Acad. Sci., 46 Ulyanov str.,
Nizhny Novgorod 603600, Russia
This paper considers the method of determining the effective acoustical
scattering cross section (S[inf eff]) for an object of arbitrary form or
determining the contribution of its part into S[inf eff]. The method is based on
the determination of transfer coefficients by direct and reciprocal methods and
calculation of S[inf eff] using the equation (without the diagram coefficient):
S[inf eff]((Omega))/S~[inf F]x[inf V], where S is the total square of the object, (Omega) is the
angular position of the point in the external field, [inf F] is the root-mean-square value of the transfer coefficient
linking the force F with the acoustic field, which is determined by the
reciprocal method, [inf V] is the root-mean-square
value of the transfer coefficient linking the vibrovelocity V on the surface of
the object with the acoustic field, which is determined by the direct method.
The root-mean-square values of K are determined over the necessary number of
points on the surface of the object. The method proposed shows high noise
protection in the experimental investigations. This method allows one to use a
powerful generator and vibrator to increase the signal/noise ratio. The
experimental results are presented.