An efficient mass-preserving interface-correction level set/ghost fluid method for droplet suspensions under depletion forces

JOURNAL OF COMPUTATIONAL PHYSICS

卷:353

Article

Ge, Zhouyang¹  Loiseau, Jean-Christophe² 

[1] KTH Mech, Linne Flow Ctr, S-10044 Stockholm, Sweden

[2] Arts & Metiers ParisTech, Lab DynFluid, 151 Blvd Hop, F-75013 Paris, France

关键词: Multiphase flow;    Level set method;    Ghost fluid method;    Colloidal droplet;    Depletion force;   

DOI  :  10.1016/j.jcp.2017.10.046

来源: Elsevier

【 摘 要 】

Aiming for the simulation of colloidal droplets in microfluidic devices, we present here a numerical method for two-fluid systems subject to surface tension and depletion forces among the suspended droplets. The algorithm is based on an efficient solver for the incompressible two-phase Navier-Stokes equations, and uses a mass-conserving level set method to capture the fluid interface. The four novel ingredients proposed here are, firstly, an interface-correction level set (ICLS) method; global mass conservation is achieved by performing an additional advection near the interface, with a correction velocity obtained by locally solving an algebraic equation, which is easy to implement in both 2D and 3D. Secondly, we report a second-order accurate geometric estimation of the curvature at the interface and, thirdly, the combination of the ghost fluid method with the fast pressure-correction approach enabling an accurate and fast computation even for large density contrasts. Finally, we derive a hydrodynamic model for the interaction forces induced by depletion of surfactant micelles and combine it with a multiple level set approach to study short-range interactions among droplets in the presence of attracting forces. (C) 2017 Elsevier Inc. All rights reserved.

【 授权许可】

Free