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.
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.
thanks for your fast response. That was the right hint.