平底结构砰击压力的分布

物体以一定的速度撞击水面,会受到水的砰击力的作用.这种砰击压力持续的时间通常很短,但量值有时会很大.本文利用仿真软件对平底刚性结构的入水问题进行了研究,建立了二维有限元模型,对平底结构分别以不同速度等速入水的情况进行了计算.计算发现,在结构入水前瞬间,作用在结构上的压力迅速增大,在到达原静水面位置稍后的位置处达到峰值.压力持续的时间随着结构入水速度的增加而减小;砰击面上的压力分布也不是均匀的,在平底中心处最大,向两侧逐渐减小.作者在对砰击压力的作用时间和在砰击面上的分布情况做了详尽的分析后,导出了砰击压力在砰击面上分布和持续时间的计算公式.

The Distribution of Slamming Pressure on Flat-Bottom Structure

While an object enters into the water with a certain velocity, it will get pressure from the water. Usually the pressure will persist in a short time but the quantity of it is rather great. Some researches about the water entry of flat-bottom structure are performed by means of simulation software in this paper. 2-D finite element model is established and many cases including the flat-bottom structure with different constant velocity entering into the water are calculated. After analyzing the results of simulation, it is found that at the moment of structure arriving the water surface the pressure acting on the slamming surface increases quickly and comes to peak value at the position of the primary water surface. The persisting time of the slamming pressure shortens as the increasing of the slamming velocity of the structure. The pressure on the slamming surface is also not even. Center position of the slamming surface gets the biggest pressure while the edge gets small. Authors analyze the persisting time and distribution of the slamming pressure and regress a formula of the pressure distribution on the slamming surface.