EFFECTS OF DIRECTIONAL SEA IN MODEL TESTING

It is shown that the currently used methods of determining mooring forces by model testing tend to produce results on the safe side. The reason is that waves in model tests are generated as waves with very long fronts. Natural seastates due to storms are typically short crested resulting in smaller wave particle velocities than predicted by the long fronted theory. The difference between the two approaches is determined by tests with a fixed-moored tanker exposed to wave trains which are accurate reproductions of measured wave trains in nature. In order to evaluate the feasibility of exposed fixed-moored vessels the use of three-dimensional waves in the analysis is necessary.