ABSTRACT

The motion response of a ship in a cross sea is studied based on computational fluid dynamics. Firstly, according to the established numerical pool, and based on the Reynolds-averaged Navier–Stokes equations and the re-normalisation group K–ϵ turbulence model, the free surface is treated by the volume of fluid(VOF) method, and a numerical simulation method is established. The wave results obtained by the numerical simulation are compared with theoretical waves to verify the reliability of the method. Then, considering the DTMB5415 ship model, a prediction method for the ship’s motion in a cross sea is established by using an overlapping mesh and VOF technology. The influence of a cross sea on ship motion performance under different wave direction angles, different wave heights and for different periods is analyzed. In addition, a method is also established for studying the ship’s motion response based on potential flow theory, and it is found that ships sailing under superimposed waves will exhibit the phenomenon of beat vibration. Finally, by comparing the results obtained by the two methods, the consistency of the two methods is verified, which provides a strong basis for the safety assessment of ships in cross seas.

摘要

基于计算流体动力学研究船舶在跨海中的运动响应。首先，根据建立的数值池，基于雷诺平均纳维-斯托克斯方程和重归一化群K – ε湍流模型，采用流体体积法（VOF）处理自由表面，建立了数值模拟方法。将数值模拟得到的波浪结果与理论波浪进行对比，验证了该方法的可靠性。然后，针对DTMB5415船模，采用重叠网格和VOF技术建立了跨海船舶运动预测方法。分析了不同波向角、不同波高、不同周期下横海对船舶运动性能的影响。此外，还建立了基于势流理论研究船舶运动响应的方法，发现在叠加波浪下航行的船舶会出现拍振现象。最后，