Simplified approach to assess the dynamic response of a container ship subjected to bow slamming load

Abstract

Simplified approach to assess the dynamic response of a container ship subjected to the bow slamming load, resulting in a transient vibratory response, typically called a ‘whipping’, is presented. The accurate numerical modelling is very complex and involves coupling of the hydrodynamic and structural solution at every time step, leading to huge computational and workload cost. Thus, the one-way coupling methodology is adopted, and hydrodynamic loads are derived using linear strip theory in the first step and applied to the FE beam model. Structural response is obtained in the time domain using an explicit dynamic solver. Extreme bending moment is derived and compared with the normative values of the wave-induced bending moment. Comparing to more accurate methods, the presented approach seems to overestimate the bending moment and leads to a conservative design. Thus, it may be used in the early stages of the design, where fast and reliable methods are essential.