近岸航行邮轮水动力数值分析研究

Numerical Analysis of Hydrodynamic Quantities of Cruise Ship Moving along Bank Wall

在港口等限制航道内大型船舶受到水流阻塞的影响,水动力性能会发生显著变化,对航行安全带来潜在危险。论文以近岸航行大型邮轮为研究对象,采用基于计算流体动力学(CFD)的雷诺平均纳维尔-斯托克斯(RANS)方法,对不同水深傅汝德数下的邮轮粘性绕流场进行数值模拟和水动力预报。为掌握数值计算误差及可靠性,构建一系列加密网格,对邮轮水动力进行网格收敛性分析。在此基础上,开展深水和浅水中的数值计算,获得邮轮纵向力、横向力、横倾力矩和转艏力矩,并由流场分析得到浅水效应与岸壁效应联合作用下的邮轮水动力特性。

Large ships generally encounter pronounced blockage effects of the confined water in harbors. It may greatly change the hydrodynamic performance of the ship and may give rise to potential danger to the navigation safety of large ships in those waterways. The present paper aims at the investigation of hydrodynamic features for a cruise ship moving along the bank with computational fluid dynamics tools. Viscous flows around the cruise ship at low and high water-depth Froude numbers are simulated by Reynolds averaged Navier-Stokes equations, and hydrodynamic forces and moments acting on the cruise ship are predicted. Prior to the systematic simulation, a grid convergence study with a set of uniformly refined grids is made by curve fits from least squares root method for the verification purpose, from which the numerical error and uncertainty are estimated. Based on the selected grid density from the grid convergence study and a series of numerical simulations, the longitudinal force, lateral force, roll moment, and yaw moment against different ship-to-bank distances is predicted under both deep-water and shallow-water conditions. Besides, physical mechanisms of both effects of the shallow-water and the bank are analyzed through flow visualizations.