Statistical Analysis and Accuracy of PIV Data

Article type: Research Article

Authors: Ullum, U. | Schmidt, J.J. | Larsen, P.S. | McCluskey, D.R.

Affiliations: Department of Energy Engineering, Fluid Mechanics Section, Technical University of Denmark, Building 404, DK-2800 Lyngby, Denmark | Dantec Measurement Technology A/S, Tonsbakken 16-18, DK-2740 Skovlunde, Denmark

Abstract: In an assessment of PIV measurement accuracy under practical experimental circumstances, grid-generated turbulence in its early decay (x/M = 13.6-15.2, Re_&lgr; ≈ 25) has been studied. Since a real-time processor was used, it was practical to acquire a statistically significant sample size of 3000 vector maps so that accurate turbulence statistics could be calculated. Results include moments of velocity components and spatial structures in terms of auto-correlations, turbulence scales and spectra. Data fall within limits of standard error estimates. This study demonstrates the need for large sample sizes, particularly for higher order statistics.

Keywords: PIV, accuracy, grid turbulence, spatial structure, statistics

Journal: Journal of Visualization, vol. 1, no. 2, pp. 205-216, 1998