基于MQ插值的变形网格在船舶阻力预报中的应用

在非结构切分网格的框架下，发展了一种基于Multi-Quadric插值的变形网格技术，结合CFD软件STAR-CCM+，采用SST湍流模型，并以VOF法进行自由液面的追踪，将该变形网格技术应用于带附体穿浪双体船的阻力预报中。分别以网格的拉伸变形和斜率变形实现了阻流板和尾楔的边界运动，计算了阻流板高度为4 mm、6 mm和8 mm以及尾楔角度为5°、10°和15°时的工况。计算结果表明，变形网格方法与固定网格方法取得了相同的精度；同试验值相比，在不同工况下变形网格最大平均误差约为6.67%，验证了其可行性。但是，相比于固定网格方法，变形网格方法的计算时耗最大可减少40%，因此采用该变形网格方法可极大地提高带可变形附体的船舶的阻力预报效率。

Application of deforming mesh based on MQ interpolation in the ship resistance calculation

A mesh deformation technique based on multi-quadric interpolation is developed in the frame-work of unstructured trim mesh. To apply this method to the resistance calculation of a Wave Piercing Cata-maran with appendage, the CFD software STAR-CCM is used by coupling the SST turbulence model and the free surface profile is tracked by VOF method. The stretching deformation and slope deformation are used to implement the boundary motions of interceptor and stern wedge, respectively. Cases with the inter-ceptor height of 4 mm, 6 mm, 8 mm and stern wedge angles of 5°, 10°, 15° are calculated. The numerical results show that the mesh deformation method has the same degree of accuracy comparing with the mesh fixation method. Validation of this method is carried out by comparison with the experimental results; the maximum average error is about 6.67%. Comparison of time consumption shows that the mesh deformation methods get a maximum computational time reduction of 40% to the mesh fixation method. Thereby, Using this method to predict the resistance of ships with appendage can greatly increase the computation efficiency.