Simulation of the Behavior of a Ship Hull under Grounding: Effect of Applied Element Size on Structural Crashworthiness

Abstract

This work models the effect of an impact phenomenon—namely the interaction between seabed rock and a ship during its operations—on the ship structure. The collision between a tanker vessel with a conical rock is simulated, a scenario that is similar to the famous grounding of the Exxon Valdez oil tanker. The study uses finite element analysis to simulate numerical parameters that are related to structural response and the contours of the ship hull under impact loading. The traditional element-length-to-thickness (ELT) ratio of 10 is recommended in this work. ELT ratios in the range of 11 to 13 are shown to produce similar results in terms of internal energy, contact force, and structural acceleration. Additionally, the analysis time is reduced by approximately 20% for the recommended ELT ratio. This result is very helpful for researchers using finite element analysis to simulate ship accidents, since the mesh size or length of complex structures is used to maintain the efficiency and accuracy of the simulation results.