pmpsd#
[f, Syy, Hm0, fp, Tp, Tm01, Tm02] = pmpsd(U195, fp, fs, N, CalSpectralSP, dispout)
Description#
Calculate Pierson-Moskowitz spectrum (power spectral density), (Pierson and Moskowitz 1964)
Inputs#
- U195=10;
Wind velocity at 19.5 meter above surface level in (m/s)
- fp=0.33;
- Peak wave frequency (fp=1/Tp) in (Hz)If CalSpectralSP=’yes’; then fp is calculated from U195
- fs=8;
Sampling frequency that data collected at in (Hz)
- N=256;
Total number of points between 0 and fs that spectrum reports at is (N+1)
- CalSpectralSP=’yes’;
Define to calculate spectral shape parameters or not (‘yes’: calculate, ‘no’: use given parameters by user)
- dispout=’no’;
Define to display outputs or not (‘yes’: display, ‘no’: not display)
Outputs#
- f
Frequency (Hz)
- Syy
Wave Energy Power Spectrum (m^2/Hz)
- Hm0
Zero-Moment Wave Height (m)
- fp
Peak wave frequency (Hz)
- Tp
Peak wave period (second)
- Tm01
Wave Period from m01 (second), Mean Wave Period
- Tm02
Wave Period from m02 (second), Mean Zero Crossing Period
Examples#
[f,Syy,Hm0,fp,Tp,Tm01,Tm02]=pmpsd(10,0.33,2,256,'yes','yes');
References#
Pierson, W. J., & Moskowitz, L. (1964). A proposed spectral form for fully developed wind seas based on the similarity theory of SA Kitaigorodskii. Journal of geophysical research, 69(24), 5181-5190.