Sound reflection from a rigid concave/convex disk and its application to a spherical concave source Free

This paper presents an analytical technique for calculating the amplitude of reflected sound waves from a rigid concave/convex disk. The formulas for the reflectivity are derived approximately under certain geometrical restrictions using Fresnel‐Kirchhoff's diffraction formulas. Moreover, we identify the reflected sound pressure from a concave disk when a point source is located at the center of curvature with the radiated sound pressure from a spherical concave source, whose surface vibrates at the same time. Then we analyze the radiated sound pressure from a spherical concave source under this condition. To verify the validity of the approach, some experiments were performed in air. Experimental results showed good agreement between the calculated and the measured values and this confirmed the usefulness of the present technique to calculate the amplitude of reflected sound waves from a concave/convex disk.