Parametric study of catenary mooring system on the dynamic response of the semi-submersible platform

In this work, frequency and time responses analysis of the Amirkabir semi-submersible platform were obtained under the combination of wind and wave loads. The effects of buoy size and stretch of mooring line in dynamics response of semi-submersible platform are investigated. The JONSWAP wave spectrum and API wind spectrum are considered as environmental conditions. In this analysis for simulations three dimensional radiation/diffraction theories and Morison's equation of ANSYS/AQWA software are used. The obtained result shows that increasing stretch of mooring line could reduce motions of the platform, while increase the mooring line tension. Also increase in buoy size increases the amplitude of semi-submersible motion and decreases mooring line tension.