Dimensional Impact Simulation of Cylindrical Projectile with Water Surface to Predict Projectile's Behavior and the Stresses Induced in it

Prediction of hydrodynamic loads during water impact has great significance in the structural design of vehicle. Impact load of fast crafts with water surface and the slam force of waves on the members of offshore structure is common examples of this phenomenon. There is not any available theoretical tool to exactly handle this complicated phenomenon and the experimental procedures in the laboratory are both time-consuming and expensive. Several studies has been done on impact to various structures from the water. Dependence of the solution of the problem to the change in the boundary shape of the water surface, makes the problem extremely complex and difficult to solve analytically. In this project, impact of a cylindrical projectile on the water surface at different entry velocities and entry angles is examined using Euler–Lagrange method in LS-DYNA software. Three-dimensional simulation and meshing of the body has been perform in LS-DYNA and then the water and the air model has been created. Simulation results with Specified boundary conditions indicate significant effect of velocity changes on the stress, plastic strain and reduce the velocity of the projectile on water impact.