The acoustic power radiated by a circular membrane excited for vibration both by means of the edge and by external surface load

In this paper the acoustic power of the circular membrane,
excited both by the edge and external exciting forces uniformly distributed over
the whole surface, is examined. Some different amplitudes of exciting factors
and some differences between the phases of excitations were considered. It has
been assumed that the source of a sound is located in a flat, rigid and infinite
baffle and is sourrounded by a lossless and homogeneous fluid medium. The
vibrations are axisymmetric and time-harmonic. Employing the Cauchy's theorem of
residues and asymptotic formulae for the Bessel functions, the asymptotes for
active and reactive power consisting of elementary functions are obtained. The
acoustic power radiated by the membrane was shown graphically in terms of the
parameters describing both kinds of excitations. Key words: acoustic radiation
power, vibrations of a spherical membrane, excitation produced by edge and
surface loads, amplitude-phase effects.