Radication power output for two-dimensional array of transducers in water using farfield and nearfield techniques

The radiation efficiency for a two-dimensional array of transducers is determined from the acoustic power radiated to the farfield, i.e., the farfield technique. The radiation efficiency curves can be classified into three types: (a) quadrupole type (even-even mode), (b) dipole type (even-odd mode) and (c) monopole type (odd-odd mode) as suggested by Maidanik 1) for a vibrating panel. To attain a global reduction in the farfield intensity, the power output of individual transducers must be considered when designing or evaluating an active sound power control. The power output radiated from individual transducers is then determined using the nearfield technique based on the self- and mutual radiation impedances. The agreement between theoretical and experimental results is satisfactory.