The present study aims to construct a universal flow pattern map of immiscible liquids with Newtonian and non-Newtonian properties in a T-shaped microchannel. Immiscible liquid–liquid flow in a T-shaped rectangular microchan-nel with a hydraulic diameter of 267µm was experimentally studied for liquid sets with non-Newtonian and Newtonian properties. Xanthan gum aqueous solution acted as the shear-thinning dispersed phase. The apparent viscosity of the non-Newtonian liquid varied from 23 to 1265 mPa·s. Two aqueous glycerol solutions with viscosities of 130 and 506 mPa·s were taken as reference Newtonian dispersed phases. Castor oil was a continuous phase in all experi-ments. High-speed visualization of the flow was performed in order to reveal flow patterns in a range of bulk velocities from 0.087 to 29 mm/s. Flow pattern maps were constructed for all liquid sets in terms of flow rates of dispersed and continuous phases. The boundaries between flow rates were shown to be shifted relative to each other in the order of magnitude. The product of the non-dimensional parameter Weber number multiplied by the Ohnesorge number was successfully utilized to distinguish segmented and continuous flow patterns for both Newtonian and non-Newtonian liquids.
|Журнал||Interfacial Phenomena and Heat Transfer|
|Состояние||Опубликовано - 1 янв 2020|