A phase-field-based lattice Boltzmann method for moving contact line problems on curved stationary boundaries in two dimensions

In this work, we propose a phase-field-based lattice Boltzmann method to simulate moving contact line (MCL) problems on curved boundaries. The key point of this method is to implement the boundary conditions on curved solid boundaries. Specifically, we use our recently proposed single-node scheme for the no-slip boundary condition and a new scheme is constructed to deal with the wetting boundary conditions (WBCs). In particular, three kinds of WBCs are implemented: two wetting conditions derived from the wall free energy and a characteristic MCL model based on geometry considerations. The method is validated with several MCL problems and numerical results show that the proposed method has utility for all the three WBCs on both straight and curved boundaries.

Download Full-text

Contact Line Dynamics in Liquid-Vapor Flows Using Lattice Boltzmann Method

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2006-98022 ◽

2006 ◽

Cited By ~ 1

Author(s):

Shi-Ming Li ◽

Danesh K. Tafti

Keyword(s):

Boundary Condition ◽

Lattice Boltzmann Method ◽

Contact Line ◽

Lattice Boltzmann ◽

Solid Wall ◽

Hydrodynamic Theory ◽

Moving Contact Line ◽

Moving Contact ◽

Boltzmann Method ◽

Contact Line Dynamics

A mean-field free-energy lattice Boltzmann method (LBM) is applied to simulate moving contact line dynamics. It is found that the common bounceback boundary condition leads to an unphysical velocity at the solid wall in the presence of surface forces. The magnitude of the unphysical velocity is shown proportional to the local force term. The velocity-pressure boundary condition is generalized to solve the problem of the unphysical velocity. The simulation results are compared with three different theories for moving contact lines, including a hydrodynamic theory, a molecular kinetic theory, and a linear cosine law of moving contact angle versus capillary number. It is shown that the current LBM can be used to replace the three theories in handling moving contact line problems.

Download Full-text

A Study of Fluid Interfaces and Moving Contact Lines Using the Lattice Boltzmann Method

Communications in Computational Physics ◽

10.4208/cicp.411011.310112s ◽

2013 ◽

Vol 13 (3) ◽

pp. 725-740 ◽

Cited By ~ 14

Author(s):

S. Srivastava ◽

P. Perlekar ◽

L. Biferale ◽

M. Sbragaglia ◽

J.H. M. ten Thije Boonkkamp ◽

...

Keyword(s):

Boundary Conditions ◽

Lattice Boltzmann Method ◽

Contact Line ◽

Lattice Boltzmann ◽

Dynamical Behavior ◽

Pressure Jump ◽

Multiphase Model ◽

Moving Contact ◽

Wall Boundary Conditions ◽

Boltzmann Method

AbstractWe study the static and dynamical behavior of the contact line between two fluids and a solid plate by means of the Lattice Boltzmann method (LBM). The different fluid phases and their contact with the plate are simulated by means of standard Shan-Chen models. We investigate different regimes and compare the multicomponent vs. the multiphase LBM models near the contact line. A static interface profile is attained with the multiphase model just by balancing the hydrostatic pressure (due to gravity) with a pressure jump at the bottom. In order to study the same problem with the multicomponent case we propose and validate an idea of a body force acting only on one of the two fluid components. In order to reproduce results matching an infinite bath, boundary conditions at the bath side play a key role. We quantitatively compare open and wall boundary conditions and study their influence on the shape of the meniscus against static and lubrication theory solution.

Download Full-text

Development of an immersed boundary-phase field-lattice Boltzmann method for Neumann boundary condition to study contact line dynamics

Journal of Computational Physics ◽

10.1016/j.jcp.2012.08.040 ◽

2013 ◽

Vol 234 ◽

pp. 8-32 ◽

Cited By ~ 15

Author(s):

J.Y. Shao ◽

C. Shu ◽

Y.T. Chew

Keyword(s):

Boundary Condition ◽

Lattice Boltzmann Method ◽

Contact Line ◽

Phase Field ◽

Lattice Boltzmann ◽

Neumann Boundary Condition ◽

Neumann Boundary ◽

Boundary Phase ◽

Immersed Boundary ◽

Boltzmann Method

Download Full-text

A HYBRID PHASE-FIELD BASED LATTICE BOLTZMANN METHOD FOR CONTACT LINE DYNAMICS

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512008586 ◽

2012 ◽

Vol 19 ◽

pp. 50-61

Author(s):

JIANG YAN SHAO ◽

CHANG SHU ◽

YONG TIAN CHEW

Keyword(s):

Lattice Boltzmann Method ◽

Contact Line ◽

Phase Field ◽

Lattice Boltzmann ◽

Solution Process ◽

Droplet Spreading ◽

Interface Evolution ◽

Cahn Hilliard Equation ◽

Boltzmann Method ◽

Contact Line Dynamics

A hybrid phase-field based lattice Boltzmann method (LBM) is proposed in this paper to simulate the contact line dynamics. The flow field is obtained through the lattice Boltzmann equation (LBE). Concurrently, the interface capturing is accomplished by directly solving Cahn-Hilliard equation, which is the governing equation of interface evolution. A symmetric spatial discretization scheme is adopted to enhance the stability. Compared with the conventional algorithms which solve two sets of LBEs, the present method has several advantages such as reduction of the number of variables in the solution process, decoupling the mobility with relaxation time and enabling a more direct manner to implement wetting boundary conditions. The proposed algorithm is first validated through recovering the analytical profile of a surface layer. It is then applied to simulate droplet spreading on surfaces with different wettability.

Download Full-text