砰击载荷作用下船艏结构瞬态响应研究

砰击现象对高速舰船艏部局部结构破坏相当严重，对舰船和人员的安全构成较大威胁，然而由于砰击载荷的瞬态性和强非线性，其计算理论还很不成熟，舰船艏部结构在砰击作用下的应力响应更鲜有人研究。基于此，利用设计波下确定的砰击压力极值，结合以往试验测定的砰击压力随时间的变化关系，计算得到砰击压力的时空分布，然后将其施加在船艏精细有限元模型上，利用中心差分法进行数值计算，并对计算中一些关键参数的设置值做不同尝试，得到了较理想的艏部结构应力响应历程。

Transient Response of the Bow Structure Under Slamming Loads

The slamming phenomenon is ruinous to the bow structure of ships and is a grave threat to the safety of crew members, especially when ships are at middle and high speeds. Due to its inherent transient and strong non-linear property, the accurate simulation of the slamming process has been quite unsuccess- ful, and the response of the bow structure to the slamming has been rarely investigated. Therefore, this pa- per aims at calculating the slamming loads that varies with space and time by incorporating the maximum slamming load value under the design wave and the exact value of the slamming loads collected in former experiments. The transient response is then calculated by using the central difference method after the slamming loads impact the bow structure. Particularly, the time interval and a few key parameters for solv- ing the problem are presented. The results show that the stress on different elements can be obtained accu- rately, which could be further used as references during the bow structure design.