Diffraction of the sound wave from a soft disc

The problem of a plane acoustic wave diffraction by a soft disc is analyzed and numerically computed for different angle of incident including axial and glancing cases. The problem is solved in terms of the velocity potential using the mode matching technique and the analytical regularization procedure. Using the mode matching technique and the property of orthogonality of associated Legendre functions the initial diffraction problem is reduced to the infinite system of linear algebraic equations (ISLAE). By means of the analytical regularization procedure, ISLAE is reduced to ISLAE of the second kind, which allows one to obtain the solution with the given accuracy. The numerical results of far-field radiation is given.