I am getting a very weird error when i am running this files. I did a flow with turb sim and I am using it in FAST yet it keeps giving me an error every time i try it on an onshore turbine
This fst input file is almost the same to the input files for TEST18 file
I do not understand what is the problem
If i try it with another simulation(test20 from the certificate test file ), it works perfectly
I am not sure what is the problem
here is a picture
i have attached files used in here drive.google.com/open?id=1LYUXa … s06hKPIbMH
thanks
mostafa
Dear Mostafa,
Based on the error message, it looks like your FAST simulation suffers a numerical instability at the start of the simulation. From my brief look at your input files, it appears that you enabled the platform rotational degrees of freedom, but you didn’t impose any platform inertia or restraints. My guess is this leads to a numerical instability in the platform-yaw DOF. Why would you want to enable the platform rotational DOFs without restraints?
Best regards,
Please forgive me for my ignorance. I was working on an offshore simulation, so I thought on my own that I should turn on the platforms dof in an onshore like an offshore simulation without knowing the meaning behind the platforms. Thanks to your answer i discovered that i should not be turning on dof for platforms in onshore simulations as the platform is only for offshore if i understood correctly
thank you
mostafa
Dear Mostafa,
The platform DOFs should not be enabled unless there is a proper restraint modeled. The platform DOFs can be used for land-based simulations if a foundation model is considered e.g. through the user-defined external platform MCKF (CompSub=2 in OpenFAST v1.0.0).
Best regards,