粘流下高速三体船的非线性横摇阻尼预报

摘要

分别应用二维强迫运动、二维衰减运动、三维强迫运动、三维衰减运动四种CFD数值方法预报比较分析了某高速三体船的横摇阻尼,其中三维方法考虑了航速对横摇阻尼的影响.同时与多种半经验公式方法和船模试验结果进行对比,结果表明,三维CFD方法与试验值较接近,可以有效考虑主侧体干扰、附体粘性等流体非线性因素影响,适用于高速三体船的横摇阻尼预报.常规单体船横摇阻尼半经验公式中除了参数适当(Bc=7.6％～8.4％)的临界阻尼公式外普遍不适合三体船型.%Roll damping of a trimaran ship at high speed is predicted with CFD method,including 2D forced roll motion,2D decayed rolling,3D forced roll motion and 3D decayed rolling.Numerical calculations are compared with several semi-empirical formulas and model test data.It is shown that the 3D prediction is close to the model test and is the most suitable for trimaran ships,for which the flow induced by the main hull is strongly coupled with the side hulls.Traditional semi-empirical formulas of roll damping for mono-hulls,with the exception of the critical damping formula for Bc=7.6％～ 8.4％,are not useful for trimaran ship.