CFD Investigation of the Effect of Current Turbulence on the Hydrodynamic Forces on a Cylinder

Practical cases of flow-structure interactions involve ocean currents with turbulence. Ocean turbulence effects on offshore structures are of high interest due to the lack of information about its role regarding the hydrodynamic forces and fatigue load on structures. Current turbulence profiles are employed for various Reynolds numbers that are based on an isotropic geophysical turbulence model. These turbulence profiles are specified as the inflow condition for the numerical simulations over a circular cylinder. The present work consists of three parts: (i) determination of appropriate mesh and time step resolution to accommodate the turbulence, (ii) investigation of the effect of current profile turbulence on the amplitude and frequencies of the hydrodynamic forces acting on a cylinder, and (iii) study of the sensitivity of the hydrodynamic load exerted on the cylinder for a range of Reynolds numbers with a turbulent inflow profile. Spalart-Allmaras one-equation turbulence model is used for high Reynolds number simulations.