Estimation of the accuracy of the numerical description of diffraction effects in highly focused ultrasonic beams using various parabolic models and methods for setting the boundary condition

A numerical algorithm based on the wide-angle parabolic approximation for modeling diffraction effects in strongly focused ultrasound beams is presented. The accuracy of the proposed approach is evaluated and compared with other diffraction approaches: the Rayleigh integral solution; parabolic approximation solution with and without modification of the boundary condition; wide-angle parabolic approximation with different ways of setting a boundary condition.