Investigation of laminar dispersion with optical coherence tomography and optical Doppler tomography

Laminar dispersion in a serpentine microchannel with a Y-shape inlet was investigated using optical coherence tomography (OCT) and optical Doppler tomography (ODT). Dimensionless analysis was performed to understand the complex convective diffusion phenomena. It was shown that OCT/ODT is not only a visualization method but also a methodology to characterize important physics: streamwise velocity, secondary streamline, sedimentation time scale, shear dispersion. To demonstrate the capability of OCT/ODT, transient mixing was observed and three-dimensional imaging was performed.