Reply To: AQWA: Hydrodynamic response error

[S.S.S.ShankaVasuki]

I tried including the 37 matrices as you suggested and here are the results:

Hydrodynamic diffraction: The figure below shows the pitch RAO (deg/m) as a function of frequncy (rad/s) for the middle section of the bodies (1b,2b,3b,4b,5b). I tried running the diffraction analysis with the 37 connection matrices and without the connection matrices. The response of the system with 37 connection stiffness matrices is lower than when there are no connection matrices mentioned which is suprising. Because just with the mass and inertial properties of all the 15 bodies, the results are still lower than the reference values. Also when i add the structure motion amplitude, the motion looks weird as shown in the second image below. So I dont know what the error here. Could it be the z-location of CoG? The reference mention the CoG from keel to be 0.1m, hence I calculated the CoG from the waterline to be 0.03m. I hope this is correct?

So could you help me with understanding whats going wrong here?

Hydrodynamic Response: Now, for the response analysis, I turned on the beta options and included the connection stiffness matrix in the time domain analysis and I get the same error saying -  HYDRODYNAMICALLY INTERACTING STRUCTURES HAVE MOVED TOO FAR FROM ANALYSIS POSITION MOVEMENT EXCEEDS 75% STOPPED AT TIME = 0.50. as shown in the figure below. So I am not sure whats going wrong. Because I have double checked everything and it seems to be okay.