Numerical Study of Interactions Between Phase II of OC4 Wind Turbine and Its Semi-Submersible Floating Support System
The motion response of the floating support system is critical in designing and confirming the safety and efficiency of an offshore wind turbine. This paper aims to study the interaction between the wind turbine and its semi-submersible floating system for Phase II of the Offshore Code Comparison Collaboration Continuation (OC4) project. First, the validation of wave generation and damping is performed to guarantee the accuracy of waves. Then, the grid convergence is studied to eliminate the influence of different grids. Last, the motion of the semi-submersible floating system in specific waves is compared with a parked wind turbine and with an equivalent operated wind turbine. The equivalent forces and moments of the NREL 5-MW in different wind speeds have been exerted on the rotational center of the semi-submersible floating system. The results show the influences of the wind turbine on the supporting system in waves.
We proposed a simple method to realize optical Fourier transform during the nonlinear wave shaping processes. In this method, an integrated optical superlattice is designed to realize multiple optical functions, which plays important roles in both the nonlinear harmonic generation process and the optical Fourier Transform process. We demonstrated our method by the nonlinear generation of Airy beams as an example. It is a universal method for beam shaping and is of practical importance for designing compact nonlinear optical devices.