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Ansys Learning Forum Forums Discuss Simulation General Mechanical AQWA_RAO in time and Frequency Reply To: AQWA_RAO in time and Frequency

Shuangxing Du
Ansys Employee

Not sure what H(regular)=Hs(irregular) means.

In your time domain simulation in regular wave, did you use the Airy wave or the second order Stokes wave theory and is there any other nonlinear damping applied? 

Is the structure as a free floating structure (without any constraint) in the time domain analysis? If yes, the coupling effects of other DOFs' large motions may affect the heave motion. 

From the curve of the heave RAO vs frequency, the interested frequency point  (1.2Hz) is close to the heave natural frequency. Near the natural frequency, the amplitudes of RAOs are sensitive to the damping applied.Â