【摘要】 本文中研究规则波浪下经典Spar平台垂荡-纵摇耦合运动内共振动力特性.考虑垂荡频率与纵摇频率的2∶1的内共振关系,在无系泊状态下建立了平台非线性耦合运动微分方程.应用MOSES软件建立了平台模型,计算了不同波浪周期下的一阶波浪激励力.采用多尺度方法求解垂荡-纵摇耦合运动响应的定常解并进行数值验证.计算结果表明,当波浪频率接近垂荡固有频率且波高达到某一极限时,平台垂荡运动的能量达到饱和;当波高继续增加时,垂荡能量开始向纵摇运动转移,导致平台发生大幅纵摇运动.更多还原

【Abstract】 We focus on the internal resonant characteristic of heave-pitch coupled motions of a classic Spar platform in regular seas.The nonlinear coupling equations for heave and pitch without mooring lines were established under the condition of internal resonance in which the ratio of heave natural frequency to pitch natural frequency is 2∶1.A model of a classic spar was founded by using MOSES software and the first-order wave exciting forces were calculated in different wave periods.The method of multiple scales was used to determine the steady-state response which was verified by the numerical calculations when the wave frequency was near the heave resonant frequency.Results show that the energy of heave mode is saturated when the wave height arrives at a certain value,and as the wave height increases further,the extra energy of heave mode is transferred to the pitch mode and large-amplitude pitch response is induced.更多还原