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Experiments in Fluids

, Volume 39, Issue 3, pp 614–622 | Cite as

Improvements to PIV image analysis by recognizing the velocity gradients

  • H. NobachEmail author
  • C. Tropea
Research Paper

Abstract

Two iterative PIV image processing methods are introduced, which utilize displacement and deformation of the interrogation areas to maximize the correlation. The velocity gradients used for the window deformation are iteratively estimated directly from the images and no velocity values are required from neighbouring interrogation areas, as with numerical differentiation. The improved accuracy and resolution of the velocity gradient estimation compared to numerical differentiation is shown using synthetic images. The performance in a real application is shown using experimental reference images.

Keywords

Particle Image Velocimetry Velocity Gradient Weighting Scheme Velocity Estimate Numerical Differentiation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

Funding from the Deutsche Forschungsgemeinschaft under grant Tr 194/21 is gratefully acknowledged.

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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.Fachgebiet Strömungslehre und AerodynamikTechnische Universität DarmstadtDarmstadtGermany

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