STUDY OF THE 430-LITER WATER-FILLED CYLINDRICAL ACOUSTICAL RESONATOR

Measurements were taken at atmospheric pressure in a cylindrical seamless vessel, which was made of 4.3mm sheet aluminum, is 55 cm by 100 cm inside liameter. Eadiation through the air was minimized by selecting the distances of the surface of the resonator from the outer cylindrical chamber or the reflecting surface. The lowest decay rates obtained at approximately 3 and 7 kHz were 0.15 dB/s and 0.30 dB/s, respectively. Thus, measurable values of absorption coefficient by this apparatus may be about 0.1 dB/km. The minimum values of absorption coefficient measured by other authors using the resonator method are cited for comparison.