Study of Liquid-Liquid Dispersion of High Viscosity Fluids in SMX Static Mixer in the Laminar Regime

Abstract

<p>In this research, liquid-liquid dispersion of viscous fluids was studied in an SMX static mixer in the laminar regime. Backlighting technique was used for flow visualization, and the Hough transform for circle detection was used in OpenCV to automatically detect and measure drop diameters for obtaining the size distribution. Silicone oil and an aqueous solution of high fructose corn syrup were used for dispersed and continuous phases respectively, and sodium dodecyl sulfate was used as the surfactant to modify the interfacial tension. Experiments were conducted at varying viscosity ratios and flow rates-each at zero, low (~200 ppm) and high (~1000 ppm) surfactant concentrations. The effect of holdup was explored only for a few cases, but it was found to have a minimal effect on the weighted average diameter D₄₃.</p> <p>It was found that the superficial velocity and the continuous phase viscosity had a dominant effect on D₄₃. The tail at the higher end of the droplet size distribution decreased with increasing superficial velocity and continuous phase viscosities. It was also found that D₄₃ decreased with lowering of the interfacial tension. Furthermore, the effect of the dispersed phase viscosity was significant only at non zero surfactant concentrations.</p> <p>An approximate model has been proposed that relates D₄₃ to the capillary number. It is based on an energy analysis of the work done by the viscous and surface forces on a drop of an initial diameter that is largely determined by the gap distance between the cross bars in the element</p>