当海上多船联合作业时,船体之间会发生水动力干扰。当间距较小时,两船的水动力参数与间距内部波面升高在某些频率处存在强烈的共振现象,而基于理想流体的经典势流理论对此共振结果的模拟存在较大失真。为了弥补此项问题,文章采用加盖阻...当海上多船联合作业时,船体之间会发生水动力干扰。当间距较小时,两船的水动力参数与间距内部波面升高在某些频率处存在强烈的共振现象,而基于理想流体的经典势流理论对此共振结果的模拟存在较大失真。为了弥补此项问题,文章采用加盖阻尼法(damping lid method)对3 m间距旁靠布置的两艘相同驳船的水动力干扰现象进行研究。通过在间距内部的自由液面边界条件上添加阻尼耗散项,使间距内部的过大波面升高被显著抑制,从而得到更接近实际的数值计算结果。在此基础上开展模型试验研究,通过对比模型试验与数值模拟结果发现,当无量纲阻尼参数ε取为0.026时,两船之间自由液面升高、两船的运动响应与平均漂移力计算结果均与试验结果吻合较好。展开更多
Simulating the coupled motions of multiple bodies in the time domain is a complex problem because of the strong hydrodynamic interactions and coupled effect of various mechanical connectors. In this study, we investig...Simulating the coupled motions of multiple bodies in the time domain is a complex problem because of the strong hydrodynamic interactions and coupled effect of various mechanical connectors. In this study, we investigate the hydrodynamic responses of three barges moored side-by-side in a floatover operation in the frequency and time domains. In the frequency domain, the damping lid method is adopted to improve the overestimated hydrodynamic coefficients calculated from conventional potential flow theory. A time-domain computing program based on potential flow theory and impulse theory is compiled for analyses that consider multibody hydrodynamic interactions and mechanical effects from lines and fenders. Correspondingly, an experiment is carried out for comparison with the numerical results. All statistics, time series, and power density spectra from decay and irregular wave tests are in a fairly good agreement.展开更多
The hydrodynamic interaction between two vessels in a side-by-side configuration attracted research attentions in recent years. However, because the conventional potential flow theory does not consider the fluid visco...The hydrodynamic interaction between two vessels in a side-by-side configuration attracted research attentions in recent years. However, because the conventional potential flow theory does not consider the fluid viscosity, in the hydrodynamic results, the wave elevations were overestimated in the narrow gap under resonance conditions. To overcome this limitation and investigate the complex fluid flow around multiple bodies in detail, this study examines the fluid resonance between two identical floating barges using a viscous flow analysis program FLOW-3D. The volume of fluid method is implemented for tracking the free surface, and a porous media model is used near the outflow boundary to enhance the wave absorption. A three-dimensional numerical wave basin is established and validated by comparison with the waves generated using theoretical values. On this basis, a computational fluid dynamics （CFD） simulation of the two barges in a resonance wave period is performed, and the wave elevations, the fluid flow around the barges, and the motions of the barges are discussed. The numerical simulation is verified by comparison with results of corresponding experimental data.展开更多
基金Supported by Youth innovation fund of State Key Laboratory of Ocean Engineering(No.GKZD010059-21)~~
文摘当海上多船联合作业时,船体之间会发生水动力干扰。当间距较小时,两船的水动力参数与间距内部波面升高在某些频率处存在强烈的共振现象,而基于理想流体的经典势流理论对此共振结果的模拟存在较大失真。为了弥补此项问题,文章采用加盖阻尼法(damping lid method)对3 m间距旁靠布置的两艘相同驳船的水动力干扰现象进行研究。通过在间距内部的自由液面边界条件上添加阻尼耗散项,使间距内部的过大波面升高被显著抑制,从而得到更接近实际的数值计算结果。在此基础上开展模型试验研究,通过对比模型试验与数值模拟结果发现,当无量纲阻尼参数ε取为0.026时,两船之间自由液面升高、两船的运动响应与平均漂移力计算结果均与试验结果吻合较好。
基金financially supported by Lloyd’s Register Foundation(LRF),a UK-registered charity and sole shareholder of Lloyd’s Register Group Ltd.the Youth Innovation Fund of State Key Laboratory of Ocean Engineering(Grant No.GKZD010059-21)
文摘Simulating the coupled motions of multiple bodies in the time domain is a complex problem because of the strong hydrodynamic interactions and coupled effect of various mechanical connectors. In this study, we investigate the hydrodynamic responses of three barges moored side-by-side in a floatover operation in the frequency and time domains. In the frequency domain, the damping lid method is adopted to improve the overestimated hydrodynamic coefficients calculated from conventional potential flow theory. A time-domain computing program based on potential flow theory and impulse theory is compiled for analyses that consider multibody hydrodynamic interactions and mechanical effects from lines and fenders. Correspondingly, an experiment is carried out for comparison with the numerical results. All statistics, time series, and power density spectra from decay and irregular wave tests are in a fairly good agreement.
基金Project supported by the National Natural Science Foun-dation of China(Grant No.51509152)
文摘The hydrodynamic interaction between two vessels in a side-by-side configuration attracted research attentions in recent years. However, because the conventional potential flow theory does not consider the fluid viscosity, in the hydrodynamic results, the wave elevations were overestimated in the narrow gap under resonance conditions. To overcome this limitation and investigate the complex fluid flow around multiple bodies in detail, this study examines the fluid resonance between two identical floating barges using a viscous flow analysis program FLOW-3D. The volume of fluid method is implemented for tracking the free surface, and a porous media model is used near the outflow boundary to enhance the wave absorption. A three-dimensional numerical wave basin is established and validated by comparison with the waves generated using theoretical values. On this basis, a computational fluid dynamics （CFD） simulation of the two barges in a resonance wave period is performed, and the wave elevations, the fluid flow around the barges, and the motions of the barges are discussed. The numerical simulation is verified by comparison with results of corresponding experimental data.
