2 research outputs found
Viscosity effects on liquid-liquid dispersion in laminar flows
Efficiency of liquid/liquid dispersion is an important stake in numerous sectors, such as
the chemical, food, cosmetic and environmental industries. In the present study, dispersion is achieved
in an open-loop reactor consisting of simple curved pipes, either helically coiled or chaotically twisted.
In both configurations, we investigate the drop breakup process of two immiscible fluids (W/O) and
especially the effect of the continuous phase viscosity, which is varied by addition of different fractions
of butanol in the native sunflower oil. The global Reynolds numbers vary between 40 and 240, so that
the flow remains laminar while the Dean roll-cells in the bends develop significantly. Different
fractions of butanol are added to the oil in each case to examine the influence of the continuous phase
viscosity on the drop size distribution of the dispersed phase (water). When the butanol fraction is
decreased, the dispersion process is intensified and smaller drops are created. The Sauter mean
diameters obtained in the chaotic twisted pipe are compared with those in a helically coiled pipe flow.
The results show that chaotic advection intensifies the droplet breakup till 20% in droplet size
reduction, and also reduces polydispersity