Resonance frequencies

Dear Jason,

I’m trying to find the resonance frequencies of surge and pitch, but in the simulation results I can’t see any resonances. I have changed the pitch stiffness, AxCds and MemberCds, but I can’t see any changes in the results. Also I have turned on the towerDofs but I can’t see the 3p resonance. Could you tell me what the reason could be?
Attached I’m sending the plos for two AxCds.

Best regards

Dear Masih,

I’m sorry, but I’m not really sure I understand your question. When you say AxCds and MemberCds, are you referring to AxCd, MemberCd1, and MemberCd2 from the HydroDyn input file? Are you using white-noise wave excitation to identify resonances?

Best regards,