Experiments in Fluids

, Volume 29, Issue 2, pp 145–153

Comparison of Gaussian particle center estimators and the achievable measurement density for particle tracking velocimetry

  • M. Marxen
  • P. E. Sullivan
  • M. R. Loewen
  • B. Jähne

DOI: 10.1007/s003489900085

Cite this article as:
Marxen, M., Sullivan, P., Loewen, M. et al. Experiments in Fluids (2000) 29: 145. doi:10.1007/s003489900085

Abstract

A series of numerical simulations were conducted to investigate the performance of two particle center estimation algorithms for Particle Tracking Velocimetry: a simple three-point Gaussian estimator and a least-square Gaussian. The smallest position error for images with reasonable noise levels was found to be approximately 0.03 pixels for both estimators using particles with diameters of 4 pixels. As both estimators performed equally well, use of the simple three-point Gaussian algorithm is recommended because it executes 100 times faster than the least-square algorithm. The maximum achievable measurement density and accuracy for the three-point Gaussian estimator were determined with a numerical simulation of an Oseen vortex. Uncertainty measures have been introduced to filter out unreliable displacement measurements. It was found that 4 to 5 velocity vectors could be obtained within a 32 × 32 pixel area with an average displacement error of 0.1 pixels. This doubles the spatial resolution of conventional cross-correlation based Particle Image Velocimetry at comparable accuracy.

Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • M. Marxen
    • 1
  • P. E. Sullivan
    • 1
  • M. R. Loewen
    • 1
  • B. Jähne
    • 2
  1. 1.Department of Mechanical and Industrial Engineering University of Toronto Toronto, CanadaCA
  2. 2.Interdisziplinäres Zentrum für wissenschaftliches Rechnen Universität Heidelberg, GermanyDE
  3. 3.Department of Civil and Environmental Engineering University of Alberta Edmonton, CanadaCA