摘要
准确预报船舶在波浪中的运动和力可以为船舶性能评估提供参考。采用naoe-FOAM-SJTU求解器,数值模拟固定和放开垂荡、纵摇自由度的KCS船在不同波长的迎浪规则波中的运动。首先运用数值造波方法生成不同波浪周期的Stokes一阶深水规则波,与Stokes波的理论值对比确保造波的准确性;然后计算固定或放开垂荡和纵摇自由度的KCS船在0.65≤λ/L(波长/船长)≤1.95的遭遇波中的运动和阻力,研究KCS船的波浪增阻中绕射和辐射成分,且采用傅里叶分析法研究了运动与阻力的线性和非线性成分分布。结果表明,波浪绕射增阻受波长的影响不大,当波长接近船长时,船舶的垂荡和纵摇幅值以及波浪增阻均达到峰值,这主要由船体剧烈运动引起的辐射增阻导致,应避免船舶在此工况下航行。
It is significant to accurately predict the motions and added resistance for safety and comfort of a ship in waves.Based on overset grid,the in-house computational fluid dynamics solver,naoe-FOAM-SJTU,is used to calculate the motions and added resistance of KCS in regular head waves.The KCS with fixed or free heave and pitch is simulated to analyze radiation and diffraction effects.Firstly,the first-order Stokes waves with different periods in deep water are generated in a numerical wave tank.Then the motions and added resistance of KCS in regular head waves(0.65≤λ/L(wavelength/ship length)≤1.95)are computed.The variations of resistance,pitch and heave show good agreement with experimental results.In addition,their nonlinear components are analyzed by fast Fourier transform(FFT).It shows that the diffraction added resistance is not relevant to the wavelength.And the amplitudes of heave,pitch and added resistance reach a peak when the incident wavelength is close to the ship length,which is mainly caused by the radiation effect caused by the drastic motions.Hence,the ship should be prevented from voyage under this condition.
作者
郭浩
王建华
万德成
GUO Hao;WANG Jianhua;WAN Decheng(Computational Marine Hydrodynamics Lab(CMHL),State Key Laboratory of Ocean Engineering,School of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《海洋工程》
CSCD
北大核心
2020年第6期11-23,共13页
The Ocean Engineering
基金
国家自然科学基金项目(51809169,51879159,51490675,11432009,51579145)
长江学者奖励计划(T2014099)
上海高校特聘教授(东方学者)岗位跟踪计划(2013022)
上海市优秀学术带头人计划(17XD1402300)
工信部数值水池创新专项课题资助项目(2016-23/09)。
关键词
规则波
船体运动
重叠网格
KCS船
波浪增阻
regular waves
motion response
overset grid
KCS ship
added resistance
