Analysis of the performance of two moving mesh methods applied to semi-submerged structures with a rotational DOF

Abstract

Numerical analyses of a buoy with a rotational DOF and a Pendulor-type wave energy converter subjected to incident regular waves are carried out. The ANSYS Fluent® software, based on the Reynolds Averaged Navier-Stokes equations, is used for the free surface flow simulations. The k–ω SST turbulence model and the Volume of Fluid technique, to consider the two-phase flow, composed of air and water, are employed. The performance of two moving mesh methods are analyzed, the dynamic mesh (DM) and sliding mesh (SM) methods. The numerical results of the free decay test and the incident wave over the buoy, obtained by both moving mesh methods, show very good agreement with experimental ones. Besides, both moving methods have similar results in the case of the incident wave over the Pendulor device. The DM method required from 1.29 to 1.44 times the computational time of the SM method. Therefore, both methods have good accuracy to deal with problems that involve semi-submerged structures with a rotational DOF in a plane. However, the SM method has the advantage of requiring less computational time.