In the measurement of periodic fluid flows by laser anemometry, the velocities are often determined by sampling the Doppler signal at predetermined phase positions in the cycle. It is shown that the resulting intensity autocorrelation functions accumulated over many cycles are distorted by the sampling procedure. The form of this distortion is determined and verified experimentally. The application of a simple correction before the analysis of a correlogram is seen to greatly facilitate the measurement of mean velocities and turbulence level.
|Number of pages||4|
|Journal||Journal of Physics E: Scientific Instruments|
|Publication status||Published - 1980|