This paper presents CFD (Computational Fluid Dynamics) simulations of the performance of a planing hull in a calm-water condition, aiming to evaluate similarities and differences between results of different CFD models. The key differences between these models are the ways they use to compute the turbulent flow and simulate the motion of the vessel. The planing motion of a vessel on water leads to a strong turbulent fluid flow motion, and the movement of the vessel from its initial position can be relatively significant, which makes the simulation of the problem challenging. Two different frameworks including k-ε and DES (Detached Eddy Simulation) methods are employed to model the turbulence behavior of the fluid motion of the air–water flow around the boat. Vertical motions of the rigid solid body in the fluid domain, which eventually converge to steady linear and angular displacements, are numerically modeled by using two approaches, including morphing and overset techniques. All simulations are performed with a similar mesh structure which allows us to evaluate the differences between results of the applied mesh motions in terms of computation of turbulent air–water flow around the vessel. Through quantitative comparisons, the morphing technique has been seen to result in smaller errors in the prediction of the running trim angle at high speeds. Numerical observations suggest that a DES model can modify the accuracy of the morphing mesh simulations in the prediction of the trim angle, especially at high-speeds. The DES model has been seen to increase the accuracy of the model in the computation of the resistance of the vessel in a high-speed operation, as well. This better level of accuracy in the prediction of resistance is a result of the calculation of the turbulent eddies emerging in the water flow in the downstream zone, which are not captured when a k-ε framework is employed. The morphing approach itself can also increase the accuracy of the resistance prediction. The overset method, however, overpredicts the resistance force. This overprediction is caused by the larger vorticity, computed in the direction of the waves, generated under the bow of the vessel. Furthermore, the overset technique is observed to result in larger hydrodynamic pressure on the stagnation line, which is linked to the greater trim angle, predicted by this approach. The DES model is seen to result in extra-damping of the second and third crests of transom waves as it calculates the stronger eddies in the wake of the boat. Overall, a combination of the morphing and DES models is recommended to be used for CFD modeling of a planing hull at high-speeds. This combined CFD model might be relatively slower in terms of computational time, but it provides a greater level of accuracy in the performance prediction, and can predict the energy damping, developed in the surrounding water. Finally, the results of the present paper demonstrate that a better level of accuracy in the performance prediction of the vessel might also be achieved when an overset mesh motion is used. This can be attained in future by modifying the mesh structure in such a way that vorticity is not overpredicted and the generated eddies, emerging when a DES model is employed, are captured properly.

中文翻译：

---

通过使用不同的CFD模型预测硬翼滑行船体的性能

本文介绍了在静水条件下滑行船体性能的CFD（计算流体动力学）仿真，旨在评估不同CFD模型结果之间的相似性和差异。这些模型之间的主要区别在于它们用于计算湍流和模拟船舶运动的方式。容器在水上的滑行运动会导致强烈的湍流运动，并且容器从其初始位置开始的运动可能相对较大，这使问题的模拟变得颇具挑战性。两种不同的框架，包括k-ε和DES（离散涡流模拟）方法，被用来对船周围空气-水流的流体运动的湍流行为进行建模。刚体在流体域中的垂直运动，最终收敛到稳定的线性位移和角度位移，通过使用两种方法，包括变形和覆盖技术，对它们进行了数值建模。所有模拟都是在类似的网格结构下进行的，这使我们能够根据船舶周围湍流的空气-水流的计算来评估所应用的网格运动的结果之间的差异。通过定量比较，可以看到变形技术在高速行驶的纵倾角预测中会导致较小的误差。数值观察结果表明，DES模型可以在预测修剪角度时修改变形网格仿真的准确性，尤其是在高速情况下。在高速操作中，已发现DES模型可提高模型在计算船舶阻力时的准确性，也一样 阻力预测中更高的精度水平是对下游区域水流中出现的湍流涡流进行计算的结果，当采用k-ε构架时不会捕获到这些湍流涡流。变形方法本身也可以提高电阻预测的准确性。但是，过高方法会过度预测阻力。这种过度预测是由在船首下方产生的沿波向计算出的较大涡度引起的。此外，观察到过高技术会在停滞线上产生更大的流体动力压力，而这种滞止线上的流体动力压力与通过此方法预测的更大的修整角有关。DES模型被认为会导致尾翼第二和第三波峰的额外阻尼，因为它可以计算出船尾的更强涡流。总体而言，建议将变形和DES模型的组合用于高速船体的CFD建模。这种组合的CFD模型在计算时间上可能相对较慢，但是它在性能预测中提供了更高的准确性，并且可以预测在周围水中产生的能量衰减。最后，本文的结果表明，当使用过大的网格运动时，也可以在船只的性能预测中达到更高的准确性。将来可以通过以不过度预测涡度和产生涡流的方式修改网格结构来实现这一点。