Acoustic Properties of an Isolated Large-Size Resonator with a Cylindrical Hole

The paper examines the acoustical properties of an isolated large-size resonator with a cylindrical hole. The method for calculating sound absorption and both real and imaginary parts of impedance has been worked out. The results of calculation show that such a resonator absorbs low-frequency sound energy which increases with the enlargement of hole diameter. Sound absorption also depends on the sound wave incidence angle. The dependence of both real and imaginary parts of the hole impedance on frequency, hole diameter and sound wave incidence rate has been established. The results of investigations on the reverberation time, sound absorption coefficients and sound absorption in a model scaled 1: 25 are presented.