抄録
A fundamental theory on the overall Q of resonance in underwater and aerial organ pipes is proposed. It contains the following five mechanisms of energy dissipation or conversion governing the Q: wall vibrations, wall-borne hysteresis, wall radiation, wall boundary effects, and open end radiation. Our theory is encouraged by a relatively good agreement between theoretical and experimental Q-values. Numerical calculation of the Q due to each dissipation mechanism except the wall-borne hysteresis is carried out on two column mediums, five wall materials, and four pipe geometries. Underwater measurement of wall vibrations is moreover done, and its result makes surer the validity of our theory. An essential difference between underwater and aerial organ pipes clearly manifests itself as a decisive difference in their own governing dissipation mechanisms due to the differences between water and air.