Depending on the project phase air gap analysis can be carried out using frequency domain diffraction tools such as Diffrac, time domain simulations with aNySIM XMF and/or model tests in one of MARIN’s high-end facilities. aNySIM XMF can simulate the wave frequent and low frequent motion behaviour of one or multiple (floating) bodies with hydrodynamic interactions. If large nonlinear effects are expected air gap analysis can be carried out through model tests. Model test results can also be used to verify simulation results and provide input to simulations and determine applied correction factors (e.g. wave asymmetry factor, alpha).

If air gap exceedance is detected additional model tests with a large number of force panels in the front of and underneath the platform deck can be carried out to determine impact loads on the deck box of the floater.

In addition to model tests CFD simulations can also be carried out to determine impact loads. In this case, the number of simulations is typically restricted due to computational limits, however more detailed flow information is available, e.g. on the distribution of the impact load on the deck box.