基于船体梁的船体弹性变形预报方法

将船体简化成一根两端完全自由、质量和刚度沿船长方向分布不均匀的变截面梁,采用迁移矩阵法算出船体梁的固有频率和振形;将三维势流理论和结构动力学方程相结合,求出船体振动的主坐标,再利用模态叠加原理得到计算点的幅频位移响应;利用谱分析方法计算不同工况时的船体变形,并根据雷利分布得到其统计值。以某船为例,利用该方法计算船体相对变形,并对结果进行分析,得到了船体变形随着航速大小和浪向角改变的规律。

The Elastic Deformation Prediction Method of Hull Based on two - dimensional beam

The deformation of the hull will affect the equipment normal operation on board during the use of the ship, therefore, at the beginning of the design, it is necessary to accurately describe and analyze the specific parts deformation of the hull. In this paper, at first the hull simplified into a completely free at both ends, the quality and stiffness along the length of the ship in the distribution of uneven cross-section beam, the natural frequency and shape of hull girder are calculated by using the migration matrix method. Then, by combining the three-dimensional potential flow theory and the structural dynamic equation, we can find out the main coordinates of the hull vibration, and then the modal superposition principle can be used to calculate the displacement response of unit amplitude. Finally, the hull deformation at different working conditions is calculated by spectral analysis method, and its statistical value is obtained according to the Rayleigh distribution. In this paper, the relative deformation of a ship is calculated according to the above calculation method, and the result is analyzed.