基于OpenFOAM的船舶联合作业问题研究

Research on joint operation of ships based on OpenFOAM

采用势流模型以及粘性流模型,对船舶与海洋工程中船舶并联作业时形成的窄缝在波浪作用下发生的共振现象进行了研究。对于并联双箱模型,数值结果表明,当波浪以一定的频率入射时,共振现象将会发生,并联作业的船舶间水体波动将达到较大的幅值。势流模型可以较为准确地预测共振频率,但会过高地估计共振波幅。粘性流模型可以准确地模拟共振现象,但基于OpenFOAM的粘性流模型往往需要较高的计算资源以及较长的计算时间。在势流模型中,当在自由水面引入人工阻尼时,势流模型也可以得到与粘性流相近的结果,且具有很高的效率。通过势流模型与粘性流模型的对比,有助于加深学生对于流体力学的认知,并促使学生对在实际工程问题中采用何种模型进行思考。

The potential flow model and the viscous flow model are used to investigate the resonance phenomenon under the action of waves in the gap of two ships operating in parallel.For the paralleled two-box model,the numerical results show that when the incident wave frequency is at a certain value,the resonance phenomenon will occur,and the free surface level in the gap between the ships will reach a large amplitude.The potential flow model can predict the resonant frequency accurately,but the resonant wave amplitude is estimated too high.The viscous flow model can accurately simulate the resonance phenomenon,but the viscous flow model based on OpenFOAM often requires high computational resources and long calculation time.In the potential flow model,when artificial damping is introduced on the free surface,the potential flow model can also obtain results close to the viscous flow and has high efficiency.By comparing the potential flow model with the viscous flow model,it is helpful to deepen the understanding of the students on fluid mechanics and encourage students to think about which model to use in practical engineering problems.