Experimental study of enhanced mixing induced by particles in Taylor–Couette flows

• Published in: Chemical engineering research & design 2016-04, Vol.108, p.109-117
• Main Authors: Dherbécourt, D., Charton, S., Lamadie, F., Cazin, S., Climent, E.
• Format: Article
• Language: English
• Subjects: Coupled PIV–PLIF techniques; Fluid Dynamics; Mixing enhancement; Physics; Suspensions; Taylor–Couette flows
• ISSN: 0263-8762; 1744-3563
• DOI: 10.1016/j.cherd.2016.02.025

•Coupled PIV–PLIF measurements have been achieved in two-phase Taylor–Couette flow.•Efficient image processing enabled accurate measurement of concentration evolution.•The twofold effect induced by a dispersed phase on mixing is highlighted.•The separate effect of the particles size and hold-up is discussed. Local mixing dynamics was recently investigated experimentally in Taylor–Couette single-phase flow, thanks to simultaneous Particle Image Velocimetry (PIV) and Planar Laser-Induced Fluorescence (PLIF) techniques. The results highlighted the influence of the successive flow bifurcations and the role of azimuthal wave states on the dispersion of dye injected in Taylor–Couette flows. The present work extends this study to two-phase configurations with spherical solid particles. The respective effect of particle size and concentration on the vortices size and transition thresholds between the various flow regimes has been examined thanks to flow visualizations and PIV measurements. These hydrodynamic features have been complemented with PLIF experiments, that revealed a drastic enhancement of mixing due to the presence of particles regardless of the flow regime, highlighting the existence of significant particle-induced mixing in Taylor–Couette flows.