Abstract
An adaptation of the original median test for the detection of spurious PIV data is proposed that normalizes the median residual with respect to a robust estimate of the local variation of the velocity. It is demonstrated that the normalized median test yields a more or less ‘universal’ probability density function for the residual and that a single threshold value can be applied to effectively detect spurious vectors. The generality of the proposed method is verified by the application to a large variety of documented flow cases with values of the Reynolds number ranging from 10−1 to 107.
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Appendix
Appendix
The normalized median test in pseudo code and implemented as a Matlab macro.
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Westerweel, J., Scarano, F. Universal outlier detection for PIV data. Exp Fluids 39, 1096–1100 (2005). https://doi.org/10.1007/s00348-005-0016-6
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DOI: https://doi.org/10.1007/s00348-005-0016-6