Estimation of wind force acting on huge floating ocean structures

Wind forces acting on huge pontoon type ocean structures are so large that the estimation of them is important. The authors have carried out wind tunnel experiments on wind forces of friction forces, wind direction effects and effects of corners. Depending on results of experiments, they have investigated the way to estimate wind forces acting on huge pontoon type floating structures. In this estimation, effects of boundary layer, corners, friction forces and wind fluctuation are included. The way of the estimation is that, at first they calculate steady friction force and pressure force respectively, and next by using these steady forces and calculated aerodynamic admittance, fluctuating forces can be calculated. From results of estimation, as the size of structure grows, the ratio of friction force becomes large and fluctuation component becomes very small because the wind fluctuation is spatially averaged.