The challenges related to floating wind turbine analysis simulations relate to the modeling of the flexible turbine tower dynamics, the rotor dynamics, and the floating platform dynamics. In order to simulate the interactions between the wind turbine and the floating platform, two existing numerical codes, FAST , developed by the National Renewable Energy Laboratory (NREL), and MLTSIM, a Technip proprietary software, were integrated into one code, MLTSIM-FAST. In this integrated program, the turbine tower and rotor dynamics are simulated by the subroutines of FAST, and the hydrodynamic loads and mooring system dynamics are simulated by the subroutines of MLTSIM.
This paper presents validation of the MLTSIM-FAST code on the basis of data from the DeepCwind floating wind turbine model tests  and . For the present MLTSIM-FAST validation study, the TLP floating wind turbine, which showed the strongest interactions between the wind turbine and the floating platform among the three platforms TLP, SEMI, and SPAR tested, is selected. The validation results are given on the basis of full scale measured and simulated motions and loads.