Chris Willert, Deutsches Zentrum für Luft- und Raumfahrt e.V.

Using PIV as multi-point optical hotwire

By limiting the field of view in particle image velocimetry to a narrow strip, both the image acquisition frequency and the number of image frames (samples) can be increased sufficiently high to reliably obtain long time-records of the profile velocity. This data forms the basis for converged velocity statistics including higher moments and also provides probability density functions, space-time correlations and frequency spectra. The PIV measurement approach has been successfully applied for the study of boundary layer turbulence in the Barrel of Ilmenau as well as in two recent EuHIT measurement campaigns at other facilities for which sample results will be shown.