(467a) Experimental Investigation of Multiphase Mixing in Annular Centrifugal Contactors Using High-Speed Imaging and Electrical Resistance Tomography (ERT)

Advanced multiphase CFD methods are being developed and applied to simulation of centrifugal contactors to aid in optimization of their design and operation and provide inputs for design/simulation tools for processes based on this technology. Such complex multiphase simulations require detailed experimental data for validation of the underlying models and local predictions of dispersed phase droplet size and overall phase distributions (macro-mixing). In situ droplet size imaging and analysis has been conducted for evaluation of dispersed phase droplet size at several locations under the rotor of an engineering scale annular centrifugal contactor. The experimental setup employs a high-power, short-pulse strobe system in conjunction with a high resolution DSLR camera to obtain striking images of liquid droplets and air bubbles at typical operating conditions. In addition, large-scale spatial distribution of phases has been interrogated with electrical resistance tomography (ERT). Custom reconstruction techniques are employed to account for the complex geometry of the under-rotor region of the centrifugal contactor. Comparisons are made for different mixing vane configurations and corresponding predictions from CFD simulations to date.