Assessment of simulating underwater impact using the ICFD solver in LS-DYNA

Abstract

This thesis demonstrates that although the ICFD solver of LS-DYNA is a practical tool that can precisely model fluid and structure interaction, it is not effective for simulating the underwater impact of two objects. A numerical model was developed using the ICFD solver to simulate the submerged impact of a structure and ice at model scale. The numerical results were compared with physical experiments conducted in the laboratory. This thesis reveals that a water mesh exists between the structure and the ice model on contact, which leads to the incorrect calculation of pressure at the ice-structure contact points and causes incorrect impact force. This thesis also proposes a method to verify that the peak impact force of two objects in the water equals the peak impact force of the same objects in air with equivalent artificial added mass and velocity.