I forgot, maybe the SS in FAST are non-dimensionalised as well
No, unfortunately the dimensions are correct, there is a problem with the SS and my convolution integral then.
Dear @Massimo.Sirigu,
I’m not aware of an issue with the convolution solution of HydroDyn, assuming that the radiation damping data from WAMIT is of good quality. I do know, however, that the state-space solution in HydroDyn is only as good as the state-space fit to the WAMIT data. So, when the state-space and convolution-based solutions from HydroDyn disagree, I would generally cast “blame” on inaccuracies in the state-space fit.
I’m not too familiar with the hydrodynamic capabilities of WecSim and am not familiar with how much it is has been verified against OpenFAST/HydroDyn.
Best regards,
Hello Jason,
I found the problem. the timestep required by FAST, in this case, is higher than expected.
In my first figure, I put dt=0.05 seconds. Now I tried 0.01 and 0.0005 seconds and the results converge with the state space and convolution.
I hope this topic can be useful for someone else.
Kind regards,
Massimo
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