Drop train flow in a microtube
Abstract
This study investigates the flow of a thin annular film driven by an axial force in a microtube. Partial wetting is taken into account using the diffuse interface theory and the film dynamics is approximated by a long-wave mesoscopic model. Using time integration and path-following method, we study the different traveling waves. A rich behavior is brought to light and notably the existence of drop train with a complex spatial organization. We determine the genesis of the drop train related to the coarsening phenomenon. Increasing the domain size, the complexity of these pattern increases by breaking the translation symmetry. Thus, for low mean water content, flow in a microtube occurs via drop train patterns.