Dear OpenFAST community,
- I am using the 5MW_TLP_DLL_WTurb_WavesIrr_WavesMulti file for simulation in OpenFAST.
- I am trying to comparison of motion RAO (Figure 26-RAO WAMIT 27m) calculated by Denis Matha in “Model Development and Loads Analyis of an Offshore Wind Turbine on a Tension Leg Platform, with a Comparison to other Floating Concepts”.
- The way I do it is calculating motion RAO using white noise spectrum, with reference to the paper("Investigation of Response Amplitude Operators for Floating Offshore Wind Turbines) and forum posts
[Method]
I used 8000 seconds out of a 10000second simulation.
wave time series → Sxx (spectral density ) using Blackman-Tukey
ouput response(surge, pitch) → Sxy (spectral density) using Blackman-Tukey
motion RAO = Sxy/Sxx - For surge motion RAO, I think the peak values match and y(RAO)-values for each frequency appear to be influenced by smoothing.
However, For pitch motion RAO, the magnitude of the peak values varies significantly.
Is there something I am forgetting or doing wrong?
Please give suggestions on how to analyze.
Thank you for your help in advance.
