API wind spectrum

Dear Kevin,

Here are my answers to your questions:
(1) The user-defined wind profile option in TurbSim (WindProfileType = “USR”) only allows the user to specify a mean wind profile that varies with height, but does not support a time-varying mean profile. A similar question was discussed in the following forum topic: http://forums.nrel.gov/t/stitch-together-turbsim-timeseries/2245/6.
(2) The user-defined spectrum option in TurbSim (TurbModel = “USRINP”) allows the user to specify their own power spectrum of the u-, v-, and w-components of the wind speed at point, but it does not permit the user to specify their own spatial coherence function. To specify spatial coherence in TurbSim that differs from standard values, TurbSim supports the setting of SCMod1 = SCMod2 = SCMod3 = “GENERAL”, which then allows you to specify your own values for the spatial coherence decrement (a) and offset parameter (b) in TurbSim inputs InCDec1, InCDec2, and InCDec3, as well as your own coherence exponent (CohExp). While you can’t provide your own coherence function directly, this feature of TurbSim does make it possible to tailor the built-in coherence function as needed.

See the TurbSim User’s Guide v2.00.00 for more information: nrel.gov/wind/nwtc/assets/d … _v2.00.pdf.

Best regards,