箱式超大型浮体结构在规则波中的水弹性响应研究

Study on hydroelastic response of box-shaped very large floating structure in regular waves

利用三维线性水弹性理论研究了箱式超大型浮体结构在正弦规则波中的动力响应 ,用Bernoulli Euler梁解析解计算结构在真空中的动力特性 ,用弹性体三维势流理论计算结构的水动力系数。浮体结构在单位波幅规则波中的刚体运动幅值与DNV/WADAM程序的计算结果进行了比较 ,并给出了垂向弯曲模态的位移、弯矩随波浪频率的变化规律。由于箱式浮体结构的低阶固有频率很低 ,相应的弹性振型的响应与刚体运动耦合 ,结构在波浪中没有发现明显的低阶弹性模态谐振。

Three dimensional linear hydroelasticity theory is applied to investigate the dynamic response of a box-shaped very large floating structure (VLFS) in regular sinusoidal waves in this paper. The analytical method of Bernoulli-Euler beam is used to describe the dynamic characteristics of the structure in vacuum, while the three dimensional potential theory of flexible body is employed to calculate the hydrodynamic cofficients. The amplitudes of rigid body motions in regular waves are compared with that worked out by DNV/WADAM programme. The dynamic displacements and bending moments of the vertical bending mode are presented with respect to wave length. No significant resonance of the low flexible body modes is found due to the coupling of the responses among these modes and the rigid body modes.