不同曲率球面体入水砰击载荷数值计算

Numerical calculation of slamming load for different curvature of the sphere

从三维边界元方法出发,基于Wagner的自由液面抬升理论,采用数值仿真的方法研究了圆球入水的问题。通过数值模拟与轴对称体入水试验结果的正确性及适用性进行验证的基础上,并分析了不同半径的球体在不同速度下的入水总体受力和表面压力的变化规律。计算结果表明随着球体半径和入水速度的增加,峰值压力迅速增加,受力峰值与球体半径的平方和入水速度平方成正比关系;球体表面压力系数的分布计算结果表明,在测试点与水开始接触时压力系数最大,然后迅速减小;压力系数和入水速度无关,但和入水深度相关。

Based on Wagner’s theory,the numerical simulation by 3D BEM method was used to study the slamming problem of spheres with different curvatures. The numerical results were validated by the test data from an axisymmetric body slamming test[11]. The force acting on the body and the pressure at 5 specified locations are analyzed for the spheres with different radiuses and entry speeds. The result shows that the peak pressure increases rapidly with the increase of the radius and velocity,and the peak pressure has a linear relationship with the square of the radius of sphere and velocity. To calculate the distribution of the pressure coefficient along the surface of the sphere,we selected some test points in the sphere at different angles. The result shows the pressure coefficient has the maximum value when the test point touches water,and then decreases rapidly,and the pressure coefficient is sensative to the entry depth.