We exploit the recent developments of microfluidic technologies to investigate the collective shear-induced diffusion in suspensions of micron-sized particles. Whereas spherical particles do not diffuse on the time scale of our experiments, the results with platelike clay particles show a strong cross-stream shear-induced diffusivity at low volume fraction (phi(0)<= 0.01). Moreover, we find a linear dependence of the collective diffusion coefficient with the average shear rate (in the range 10(2)-10(4) s(-1)) and the particle concentration. These data are in good agreement with previous experimental and theoretical results for spheres when rescaled with the particle number density.
Shear-Induced Diffusion of Platelike Particles in Microchannels
Rusconi R;
2008-01-01
Abstract
We exploit the recent developments of microfluidic technologies to investigate the collective shear-induced diffusion in suspensions of micron-sized particles. Whereas spherical particles do not diffuse on the time scale of our experiments, the results with platelike clay particles show a strong cross-stream shear-induced diffusivity at low volume fraction (phi(0)<= 0.01). Moreover, we find a linear dependence of the collective diffusion coefficient with the average shear rate (in the range 10(2)-10(4) s(-1)) and the particle concentration. These data are in good agreement with previous experimental and theoretical results for spheres when rescaled with the particle number density.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
