Abstract: An are transducer array with heart-shaped directivity has been made. The frequency is 100 kHz under water, the electric impadance is 140 and the mechanical m is 6. The pressure at angle +60 was found to be 12 dBhigher than that of angle 0. The transmitting voltage sensitivity of arc at angle 60 is 163 dB and the Acoustical source level is 215 dB (Ye 1uPa/v. m).
The transduce array has a Radius of 15 cm, consisting of two idantical arcs. The radiating surface of the arc is curved copper plate to which all chord source is cecented by epoxy resin.
In view of the fact that chord sources were not accompanied by any backward radiation and that the radius,of the array considerably exceeds the wavelength in water, the results obtained by treating the far-field acoustic pressure with methods employed in Eay Acoustics are consistant with our experimental data.