Effect of Bend Wettability on Hydrodynamics of Liquid-Liquid Two- phase Flow in Serpentine Mini Geometry

In the present study, liquid-liquid flow dynamics are compared in three different geometries experimentally. These are straight glass capillary, serpentine geometry made of glass capillary, and serpentine geometry made of glass capillary with hydrophobic bends. For all cases, glass capillaries have an inner diameter of 2.4 mm and total length of 1.72 m. Four different liquid pairs are used to investigate the effect of continuous phase properties on flow distribution. Slug, slug droplet, and encapsulated slugs are noticed. The effect of the bend contact angle on flow distribution is explored. It is noticed that the presence of bends is responsible for the slug with droplet generation. Also, hydrophobic bends result in phase inversion that produces the encapsulation. On increasing the continuous phase viscosity, the range of existence of encapsulated region increases. However, the area of encapsulated phase decreases. At the same time, the shape of the encapsulated phase changes from cylindrical to spherical. An empirical correlation is proposed for area encapsulated in terms of non-dimensional numbers.

Automated summary

In this study, liquid-liquid flow dynamics are compared in three different geometries experimentally, revealing the influence of continuous phase properties on flow distribution. An empirical correlation for the area of encapsulated phase is proposed.