Auto-spectral density and cross-spectral density with MCrunch

Wind & Water Computer-Aided Engineering Software Tools
1

Hi everybody.

I am interested in obtaining the RAOs of a floating wind turbine and I am thinking of using the ratio of the cross-spectral density and the auto-spectral density of input and output signals x(t) and y(t), where the structure has been excited with white noise waves. Can I calculate the cross-spectral density and auto-spectral density using MCrunch and also take the ratio of the two in MCrunch?

2

Dear Jacob,

I agree that the method you propose is a good way of estimating Response Amplitude Operators (RAOs), especially when exciting the floating wind system with white-noise waves. But unfortunately, MCrunch does not yet support cross-correlation (neither do MExtremes or MLife). We’ve developed scripts internally at NREL for our own purposes when we’ve calculate RAOs ourselves.

Best regards,

3

Dear Jason,

Thanks for your response, OK I will look into calculating the cross-spectral response.