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Notes - Wind Turbine ISR-G (view source)
Revision as of 00:00, 24 September 2020
, 00:00, 24 September 2020no edit summary
## 9/24/2020
### Remote Wind Speed Sensing
- __two challanges__: low noise to signal ratio, need to measure volume not single point
- LIDAR & SODAR Doppler shift measuring; LIDAR measurements are more precise
### Statistical Analysis of Wind Speeds and Turbulence
- Navier-Stokes equation (evolution equation) to calculate wind speeds in space
- statistical analysis, spectra, turbulence intensity is obtained by mean wind speed and standard deviation of wind speeds
- every wavelength (after Fourrier Fourier transform) can be thought of as a length scale
- wind vector (u, v, w)
- integral length scale; from time series, we compute the auto-correlation function
- turbulence spectra
- averaging periods of 10 min are commonly used; 30 min perios period for turbulence studies; the larger integral time scale, the larger should be averaging period; sampling frequencies should be much smaller than integral time scale- you have to detrend te time series to get rid of high -frequency fluctuation
