Numerical simulation of water entry of tunnel cross section with different deadrise angles and tunnel radiuses

This study deals with the numerical modeling of symmetrical water entry of tunneled sections. In this study, firstly, the water entry problem of a wedge section without tunnel in four different deadrise angles was numerically modeled. The obtained results related to the pressure distribution on these sections and the maximum pressure have been compared with the experiment results. In the next step, the numerical simulation of the water entry problem with the tunnel section has been done. For this purpose, a tunneled section was created by adding a tunnel to a simple wedge section. Finally, the effects of changing the deadrise angle and also changing the radius of the tunnel section have been modeled. In this study, the viscous Navier-Stokes (N-S) equations are used to simulate water flow around the section and also a Volume of Fluid (VOF)-type method, is employed to capture the free surface. The results of pressure changes and maximum pressure in three different areas of the tunnel section have been obtained. These three areas include the area before the tunnel, in the tunnel area and the area after the tunnel. The results of this research indicate the occurrence of severe pressure changes in the tunnel area. Also, with the increase of the radius of the tunnel, it was observed that the amount of pressure on the section also increases. The results of this study can be used in the hydrodynamic analysis of tunneled vessels.