Campbell Diagram & MBC3 output relation

Dear Jason,

Thanks for the reply. If I understood you correctly the green/red bold fonts pinpoint pairs of tightly coupled DOFs. For example, if I know the 1st tower FA mode frequency apriori then I can use the green/red bold fonts to identify the 1st blade flapwise mode. Am I right?

I did use these MATLAB scripts for 5MW and 15MW semisubmersible cases but the interpretation of the modes still requires visual inspection as you pointed out. In fact, I posted a query (in June 2020) related to the mode identification using the MATLAB scripts (Question #1 for turbulence fields (points outside of field)) for the 5MW case, then you replied that manual interpretation is still needed.

To my knowledge, the features related to the automatic generation of excel spreadsheet and mode identification were previously available but not fully functional (at least in my case when I tried using them on Mac). I think the creation of Campbell_Summary file with information related to the coupled DOFs is a more recent update. However, it is confusing to use this information for mode picking. For example (see attached a screenshot of my Campbell_Summary file for the 15MW case), for 0 rpm the 8th DOF (with frequency=0.428Hz has last column " ED 1st FLAP cos - " while 1 rpm (frequency=0.428Hz) has the last column “ED 1st EDGE coll. - ED 2nd FLAP cos - ED 1st tower FA - ED 1st FLAP sin - ED Platform horizontal sway translation DOF - ED 1st FLAP coll.” It is not very clear to me how a mode with 0.428Hz shows different coupled DOFs contributions. This information for the same DOF is not consistent for higher rpm as well. Can you please explain how this can be possible?


Regards