Simulation of Water-Entry and Water-Exit Problems Using a Moving Mesh Algorithm

Simulation of the water-entry and water-exit particularly, at the interface of two phases i.e. water and air due to the effect of flow-induced loads, gravity force and trapped air cushion presence is very complicated. This paper attempts to introduce a finite volume-based moving mesh algorithm in order to simulate such problems in a viscous incompressible two-phase medium. The algorithm employs a fractional step method to deal with the coupling between pressure and velocity fields. Interface is also captured by solving a volume fraction transport equation. A boundary-fitted body-attached mesh of quadrilateral Control Volumes (CVs) is implemented to record hydrodynamic time histories of loads, motions and interfacial flow changes around the structure. Forced water-exit of a cylinder is simulated based on the introduced algorithm, together with free symmetric and asymmetric water-entry of wedges. Results show that the presented algorithm is favorably capable of assessing such complexities when comparing to experimental data.