I have some questions about the wind speed.
I noticed that there are 9 wind points in total for wind speed measurement, how could I figure the exact positions of them, could I change the position by myself?
For a closed loop control scheme, if the Uop depends on a lookup table based on steady wind speed, which wind speed should be referred to? Should I pick WindVx in several points for the mean value or just the Point 1?
How could I generate Turbulent wind with varying mean wind speed?
What are the following outputs used for?
Thank you very much for your kind volunteering and precious time, looking forward to your reply.
Thanks for your detailed reply. Here are my feedbacks.
I found the descriptions of Wind Point in InflowWind input file, but I didn’t find
WindList. How can I get the information about
Many controllers are implemented with set points due to the perturbation linear model. (Q1: Generally, how do they choose the OP? according to where they get the linear model?) When they are validated, turbulent wind with constant mean wind speed are usually adopted. (Q2: In cases like this, the OP will not be changed, right? ) But in natural environment, how can we define a mean wind speed of inflow wind for a wind turbine? How to divide time and zone? Or can I take the view that if the mean wind speed doesn’t change, there is no need to change the OP?
By the way, another confusion also occurred after the discussion with my colleagues working on aerodynamic. When we linearize the fast model, we used steady wind speed, and then we also get OP here. But the “wind speed” which affects the force should be a weighting sum related to blade, in turbulent cases, things may not like that in steady case. Is previous OP still effective enough?
I have ever tried TurbSim, but what it generated is with constant mean wind speed.
If I want turbulent wind with varying mean wind speed (whatever step or ramp) , is there any change that I can make in
Thanks for your kind volunteering. I’m sorry the second part is a bit disordered, if you cannot get the point, I will make it clearer next time. Looking forward to your reply
Regarding (1), InflowWind module input parameters
WindVziList are specified by the user in lines 9-11 of the InflowWind input file (as of OpenFAST v.3.2). See the InflowWind User’s Guide for more information: 4.2.9. InflowWind Users Guide and Theory Manual — OpenFAST v3.2.0 documentation.
Regarding (2), it is common for a wind turbine controller to be based on linear models, but typically multiple linear models are generated at different operating points (OP) associated with different mean wind speeds and gain-scheduling (often based on pitch angle) is used to transition across the range of conditions. Time-domain simulations of wind turbines typically involve running distinct turbulent wind simulations at different mean wind speeds, with each simulation being run for around 10 minutes and multiple turbulence seeds used at each mean wind speed. For example, covering the full operational range of a wind turbine with a cut-in wind speed of 3 m/s and a cut-out wind speed of 25 m/s could involve 66 10-minute simulations, i.e., splitting the wind speed range into 11 bins and running 6 unique simulations (6 unique seeds) within each wind speed bin (at mean wind speeds of 4 m/s, 6 m/s, …, 24 m/s). I’m not sure I understand your last question in (2), but certainly the linearized model does not include the nonlinear dynamics and full-field turbulent excitation captured by the full nonlinear model.
Regarding (3), again, wind turbine simulations with turbulence are typically run about a given mean wind speed and separate simulations are run at different mean wind speeds. Related questions have been discussed previously on this forum, e.g., see: Stitch Together TurbSim Timeseries.