Numerical simulations of free-surface waves past two vertically aligned horizontal circular cylinders

Abstract

A two-dimensional numerical model based on Navier-Stokes equations is employed to simulate free surface waves past two vertically aligned horizontal circular cylinders. The volume of fluid method is used to capture the characteristics of the free surface. The numerical simulations of free surface waves past a partially-submerged horizontal circular cylinder with different submerged depths and wave heights are carried out as validation studies of the present numerical model. The numerical results agree well with the published experimental results obtained by Dixon et al. (1979) in terms of vertical hydrodynamic forces. Free surface waves past two vertically aligned horizontal circular cylinders are computed using the validated numerical model. The influences of the spacing between the two cylinders on the vertical hydrodynamic forces on and the free surface elevations around the cylinders are investigated in the present study. The results indicate that the vertical spacing between the two cylinders has a significant effect on the vertical hydrodynamic forces of the cylinder at the lower location, while the vertical hydrodynamic forces of the cylinder at the upper location can be only affected when the vertical spacing is small.