高速船垂向振动计算的流固耦合分析

Analysis of Fluid-Structure-Coupled Vertical Vibration for High-Speed Ships

寻求一种既能提高高阶计算精度 ,又计算简便能满足工程要求的实用计算模型 ,以提高振动预报的精度 ,这对于高速船的设计计算是迫切需要的 .建立了二维模型 :杆 -膜和梁 -膜模型 ,船体结构部分采用二维有限元法计算 ,流体部分采用考虑线性自由表面条件和采用高频极限近似两种二维边界元法计算 ,应用改进的行列式搜索法以及交叉迭代法求解特征值及对应的特征向量 ,解决流固耦合问题 .通过采用不同的附加质量计算方法以及不同的模型 (杆 -膜或梁 -膜模型 )分别进行计算 ,并对结果进行了比较分析 .实船计算表明 ,编制的程序计算结果可靠 ,具有较强的工程实用价值 .

It is essential for the designer of the high-speed ship to develop a relatively simple, accurate and practical calculation model. A practical method of vertical vibration analysis for high-speed ships based on two-dimensional finite element model was proposed. The method employed for evaluating hydrodynamic added mass was two-dimensional boundary element method in which two different free surface conditions (linearized or high frequency limit simplified free surface condition) were discussed respectively. The modified determinant search method and alternate iteration method were applied to solve the coupled fluid-structure vibration. The comparison of computation results with the experiment results indicates that the developed program is reliable and practical at the design of high-speed ships.