Control of the directional response of acoustic transducer array elements on curved surfaces by modification of the diffracted field

The response of acoustic transducer elements mounted on a curved end cap on a cylinder, both of arbitrary surface impedance, for signals arriving from the rear, has been studied using the Geometrical Theory of Diffraction. A mathematical model has been generated, and results will be given for an element on an ellipsoidal end cap at several nondimensional frequencies and for several typical surface impedances, including some cases where the impedance is nonuniform.