Numerical simulation of free-surface waves past two semi-submerged horizontal circular cylinders in tandem

Two-dimensional (2D) numerical simulations are performed to investigate free surface waves past two semi-submerged horizontal circular cylinders in tandem. The 2D simulations are carried out by solving the Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations with the k-ω turbulence model. The level set method is employed to model the free-surface waves. Validation studies of a numerical wave tank have been performed by comparing the numerical simulations with free-surface waves past a partially-submerged horizontal cylinder with the published experimental data under regular-wave and deep water conditions. Cases with different submerged depths of the cylinder and incident wave properties have been studied. The numerical results are in good agreement with the experimental measurement in terms of hydrodynamic forces. Subsequently, free surface waves past two semi-submerged horizontal cylinders in tandem are computed numerically. The effect of spacing between the two cylinders is investigated by examining the changes in the vertical hydrodynamic forces on and the free surface elevations around the cylinders.