windspectrum2timeseries

[Eta, t] = windspectrum2timeseries(f, Sxx, fs, dispout)

Description

Generate zero-mean wind velocity time series from a given spectrum

Add mean of the wind velocity to generated time series to get desired time series

Inputs

f

Frequency (Hz)

Sxx

Power spectral density in ((m/s)^2/Hz)

Length of Sxx and f should be odd number

fs=2*max(f);

Sampling frequency that data collected at in (Hz)

dispout=’no’;

Define to display outputs or not (‘yes’: display, ‘no’: not display)

Outputs

U

Wind velocity time series in (m/s)

t

Time in (s)

Examples

N=2048+1; %Total number of points
fs=2; %Sampling frequency
df=fs/N; %Frequency difference
f(:,1)=[0.002:df:fs/2]; %Frequency vector
Sxx=1.0^2.*(6.868*100/10)./(1+10.32.*f.*100./10).^(5/3); %Calculate Spectrum
[U, t]=windspectrum2timeseries(f, Sxx, fs, 'yes');

References

Branlard, E. (2010). Generation of time series from a spectrum. Technical University Denmark. National Laboratory for Sustainable Energy.

Rose, S., & Apt, J. (2012). Generating wind time series as a hybrid of measured and simulated data. Wind Energy, 15(5), 699-715.

Shinozuka, M., & Jan, C. M. (1972). Digital simulation of random processes and its applications. Journal of sound and vibration, 25(1), 111-128.

Veers, P. (1984). Modeling stochastic wind loads on vertical axis wind turbines. In 25th Structures, Structural Dynamics and Materials Conference (p. 910).