Experiments in Fluids

, Volume 42, Issue 1, pp 41–48

Microscale Synthetic Schlieren

Research Article


We develop the axisymmetric Synthetic Schlieren technique to study the wake of a microscale sphere settling through a density stratification. A video-microscope was used to magnify and image apparent displacements of a micron-sized random-dot pattern. Due to the nature of the wake, density gradient perturbations in the horizontal greatly exceed those in the vertical, requiring modification of previously developed axisymmetric techniques. We present results for 780 and 383 μm spheres, and describe the limiting role of noise in the system for a 157 μm sphere. This technique can be instrumental in understanding a range of ecological and environmental oceanic processes on the microscale.


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • King-Yeung Yick
    • 1
  • Roman Stocker
    • 2
  • Thomas Peacock
    • 3
  1. 1.Department of MathematicsMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.Department of Civil and Environmental EngineeringMassachusetts Institute of TechnologyCambridgeUSA
  3. 3.Department of Mechanical EngineeringMassachusetts Institute of TechnologyCambridgeUSA

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