Application of median filtering on PIV images analysis

Abstract-With the development of flow visualizations and measuring techniques, the particle image velocimetry (PIV) is applied in experiments and researches of fluid gradually. But, the background noise is unavoidable in acquiring practical images. The experimental researches showed: the background noise, which will lead to errors or deviations in gray value of practical images, introduces errors in velocity fields and influences the results of experiments and researches. This paper adopted median filtering to process background noise, made comparisons between pre-processing and post-processing on velocity field, and gave the caused reason finally.