Dear Josean,
The scaling used to create the binary .u, .v, and .w data files breaks down at very low levels (or zero) turbulence and can lead to unexpected behavior. If you wish to generate wind without turbulence, use AeroDyn’s simple “hub-height” format wind data file instead. See the following forum topic for more information: TurbSim: incorrect flow angle at zero turbulence.
That said, when using FAST in conjunction with turbulent wind data files from TurbSim, the wind “grids” (“planes”) will propagate along the xi-axis regardless of the wind direction specified in TurbSim, which is why we always recommend setting the wind direction to zero when using TurbSim in conjunction with FAST. To model a floating offshore wind turbine with waves misaligned from turbulent wind, change the wave direction instead of the wind direction. When using AeroDyn’s so-called “hub-height wind files,” the wind direction need not align with the xi-axis.
See the TurbSim User’s Guide for more information.
Best regards,