title: Hydrodynamic interaction of two deformable drops in confined shear flow.
abstract: We investigate hydrodynamic interaction between two neutrally buoyant circular drops in a confined shear flow based on a computational fluid dynamics simulation using the volume-of-fluid method. The rheological behaviors of interactive drops and the flow regimes are explored with a focus on elucidation of underlying physical mechanisms. We find that two types of drop behaviors during interaction occur, including passing-over motion and reversing motion, which are governed by the competition between the drag of passing flow and the entrainment of reversing flow in matrix fluid. With the increasing confinement, the drop behavior transits from the passing-over motion to reversing motion, because the entrainment of the reversing-flow matrix fluid turns to play the dominant role. The drag of the ambient passing flow is increased by enlarging the initial lateral separation due to the departure of the drop from the reversing flow in matrix fluid, resulting in the emergence of passing-over motion. In particular, a corresponding phase diagram is plotted to quantitatively illustrate the dependence of drop morphologies during interaction on confinement and initial lateral separation.
authors.affiliation: Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, People's Republic of China and School of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, People's Republic of China.
authors.forename: Yongping
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, People's Republic of China.
authors.forename: Chengyao
authors.initials: C
authors.lastname: Wang
mesh_terms: D003198:Computer Simulation; D057446:Hydrodynamics; D009038:Motion; D012212:Rheology