Dear Gia,
I’m not sure about what you’ve done to get those results, but for a flexible structure, it’s not just wind load that causes shear gradients along the tower. If the tower is tilted due to flexibility or platform tilt, that will have an effect. If you just want to know how much force the wind is applying to the tower, try running FAST with no platform motion and no tower flexibility and then have one run with tower aero and one without. The difference in the shear for the two time series will tell you the tower load, although it will miss the effect of tower vibration on the aerodynamics.
Marshall
Dear Marshall,
Thank you very much for your prompt reply.
I will follow your suggestions and inform you about the results.
Kind regards,
Gia
Hi
This has been my first attempt to incorporate tower-drag loads in my analysis. To derive time series of wind speeds on the tower, I set the WrADTWR flag to TRUE in my TurbSim input file, which gives me a ‘.twr’ file as output. However, when i run FAST, I am getting an error message, which states, “Resolution in the FF binary file does not match the tower file.”
For the ElastoDyn file, I’ve kept the default value of 20, for tower nodes. In TurbSim, I am using a grid size of (2121, 155m155m). How can i ensure that the resolution of the two files match?
Sincerely
Abhinav
Hi
I guess I solved it. I generated a “.bts” file instead of a “.wnd” one, using the “lollypop” wind-field switches mentioned by Marshall Buhl in FAST: Tower Drag and Tail vane inertia - #5 by Marshall.Buhl and now FAST is running properly. I hope thus is correct. I am yet to run verification tests.
Sincerely
Abhinav