Hello,
I did run the model linearization mode in FAST and recieved *.lin file for my turbine model.
If I now try to compute the model frequencies using MBC3, I do get the following error message.
“*** There are no rotating states. MBC transformation, therefore, cannot be performed.”
The model which I linearized got only the 4 tower modes enabled. Is there any kind
of oppertunity to compute the 4 frequencies of this model using MBC3.
Thanks for your help.
Best regards,
Matthias
Dear Matthias,
The mbc3.m script that comes with the MBC3 toolset can only be used if you have a system with some states in the rotating frame. If you want to analyze a system with all states in the fixed frame, you can use the cce.m script supplied with the MBC3 toolset. The cce.m script performs the eigenanalysis directly on the azimuth-averaged state matrix, AvgAMat (regardless of whether or not the system has states in the rotating frame). This is perfectly suitable for a system with only states in the fixed frame. (For a system with some states in the rotating frame, the cce.m script employs the constant-coefficient-approximation eigenanalysis.)
I hope that helps.
Best regards,
Dear Jason,
thanks for your fast response. That was the right hint.
Best regards,
Matthias