複数の矩形浮体要素から構成される大型浮体微小間隙内での流体共振特性とその発生条件

抄録

Characteristics of resonant phenomena in narrow gaps of very large floating structure composed of a number of rectangular modules are investigated experimentally and theoretically. Especially, this study focus on the case of three modules with two gaps in order to make clear the difference with the case of one gap in which the authors have already had the experimental confirmation of occurrence of fluid resonance in the gap. Appearance conditions of fluid resonance are derived using the conservation of energy in the gaps and around two modules on the side of incident wave. In the derivation, first, two natural frequencies in the gaps are led as the frequencies described by the gravity acceleration and the geometrical conditions of floating structure including a water depth. Then, the appearance conditions are obtained substituting a dispersion relation of incident wave into the natural frequencies as kl_{1, 2}tanh kh=1 (k is the incident wave number, l_{1, 2}: l₁, l, ₂are the geometrical conditions, h is the water depth). The validity of the appearance conditions are verified by the comparison with the experimental results