On the mass source internal wave making method for ALE based numerical wave tank

摘要

In this study, we perform simulations for free surface wave tracking inside a numerical tank. A Navier-Stokes solver, combined with the arbitrary Lagrangian-Eulerian method, is introduced. To generate free surface waves, a mass source internal wave-maker, proposed by Lin and Liu (J Waterw Port Coast Ocean Eng 125(4):207-215, 1999), is employed and implemented in OpenFOAM. A line mass source distribution throughout the water depth is used to mimic a real-world wave-maker. Specifically, two types of line source wave-makers for shallow water, namely the piston and flap types, are established, together with the block mass source model used by Lin and Liu (J Waterw Port Coast Ocean Eng 125(4):207-215, 1999) . Numerical results of free surface profiles and horizontal velocity profiles are validated by experimental data (Umeyama in J Waterw Port Coast Ocean Eng 137(2):85-94, 2010) . It is concluded that in the case of shallow-water wave propagation, the line source model is better than the block source model at maintaining the wave form. The internal wave-making method has its ceiling (wave height and water depth ratio H/h=0.1for applications in numerical wave-making. Flow contamination induced by the wave-maker itself must be considered in complex flow situations such as wave-current interactions.