Wave-induced response of a closed floating fish cage consisting of a vertical circular cylinder with an external toroidal floater is studied theoretically and experimentally. A main purpose was to investigate how the internal sloshing would influence the global response of the cage, the interior wave elevation and also the mean drift loads. An ocean basin laboratory was used in order to minimize tank wall effects. An optical system involving eight markers was used to obtain experimental values for radial elastic deformations of the cylindrical part. The closer a coupled natural period between body motions and sloshing is to a corresponding natural sloshing period, the more nonlinear sloshing can be. In the examined case, the highest coupled natural period between surge, pitch and sloshing is 0.8 times the highest natural sloshing period. Linear potential flow theory can, in general, explain experimental transfer functions of rigid-body motions and sloshing due to rigid-body motions obtained by both regular wave and truncated white noise tests. Theoretical second order mean wave drift forces based on a rigid body and potential flow agree also well with experimental results. Resonant 3D sloshing was excited due to ovalizing hydroelastic structural modes in both regular waves and white-noise tests. The closeness between the corresponding structural and sloshing frequencies caused large response. A linear hydroelastic analysis based on WAMIT and LS-DYNA could partly explain the response. Parametric resonant pitch response occurred experimentally at large wave periods partially due to in and out of water motion of portions of the floater and was explained by treating the pitch as uncoupled motion modeled by the Mathieu equation. The pitch motion predicted by linear potential flow theory was, in general, unsatisfactory when the floater was partly out of the water occasionally.

从理论上和实验上研究了由带有外部环形浮子的垂直圆柱体组成的封闭浮动鱼笼的波浪诱导响应。一个主要目的是研究内部晃动如何影响笼子的整体响应、内波高程以及平均漂移载荷。使用海洋盆地实验室以尽量减少罐壁效应。使用包含八个标记的光学系统来获得圆柱部分径向弹性变形的实验值。身体运动和晃动之间的耦合自然周期越接近相应的自然晃动周期，晃动越非线性。在所考察的情况下，浪涌、纵摇和晃荡之间的最高耦合自然周期是最高自然晃荡周期的 0.8 倍。一般来说，线性势流理论可以解释刚体运动的实验传递函数和由规则波和截断白噪声测试获得的刚体运动引起的晃动。基于刚体和势流的理论二阶平均波漂移力也与实验结果非常吻合。由于常规波和白噪声测试中的椭圆化水弹性结构模式，共振 3D 晃动被激发。相应的结构频率和晃荡频率之间的接近度引起了很大的响应。基于 WAMIT 和 LS-DYNA 的线性水弹性分析可以部分解释响应。参数共振俯仰响应在大波浪周期实验上发生，部分原因是漂浮物部分的进水和出水运动，并通过将俯仰视为由 Mathieu 方程建模的非耦合运动来解释。当漂浮物偶尔部分出水时，线性势流理论预测的俯仰运动通常不能令人满意。