We use the Landau-de Gennes theory of a nematic liquid crystal to investigate anew aspects of the properties of the interface between the isotropic and nematic liquid crystal phases of the same uid. The equations of the static interface have been solved, both numerically and using asymptotic analysis, with an emphasis on the inclusion of the order parameter biaxiality on the physical properties...

for the Mini-Workshop “VMS and Stabilized FE” Stabilized Methods for Free-Surface Flow Simulations Marek Behr Chair for Computational Analysis of Technical Systems Center for Computational Engineering Science RWTH Aachen University Steinbachstr. 53B, 52074 Aachen, Germany [email protected] Free-surface flow simulations are an important design and analysis tool in many areas of engineerin...

Multiphase flows associated with interfacial dynamics, steep jumps in fluid properties and moving boundaries between different phases pose substantial computational challenges in terms of both modeling as well as computational efficiency. The present work extends a marker-based immersed boundary, or front tracking, technique to model the three-dimensional interfacial dynamics. It tracks the mov...

We present a coupled moving mesh and level set method for computing incompressible two-phase flow with surface tension. This work extends a recent work of Di et al. [SIAM J. Sci. Comput., 26 (2005), pp. 1036-1056] where a moving mesh strategy was proposed to solve the incompressible Navier-Stokes equations. With the involvement of the level set function and the curvature of the interface, some ...

In this paper we outline a front-tracking method for computing the moving contact line. In particular, we are interested in the motion of two-dimensional drops and bubbles on a partially wetting surface exposed to shear flows. Peskin’s Immersed Boundary Method is used to model the liquid-gas interface, similar to the approach used by Unverdi and Traggvason. The movement near the moving contact ...

We develop theory and numerical algorithms to apply level set methods to problems involving the transport and diffusion of material quantities in a level set framework. Level set methods are computational techniques for tracking moving interfaces; they work by embedding the propagating interface as the zero level set of a higher dimensional function, and then approximate the solution of the res...

Steep gradients of temperature and density, called cold fronts, are observed by Chandra in a leading edge of subclusters moving through the intracluster medium (ICM). The presence of cold fronts indicates that thermal conduction across the front is suppressed by magnetic fields. We carried out three-dimensional magnetohydrodynamic (MHD) simulations including anisotropic thermal conduction of a ...

The motivation underpinning this work is the need to understand bubble generation mechanisms due to interactions between free surface and turbulent boundary layers as commonly seen near ship walls. As a canonical problem, we consider a turbulent plane Couette flow with vertical parallel sidewalls and an air-water interface established by gravity in the vertical direction. Two-phase Couette flow...

Level Set and Phase Field methods are well-known interface-capturing techniques for approximation of moving interfaces. In the first part of this project, a recently developed sharp-interface phase-field method [1] is implemented in Matlab and used to implicitly capture normal interface motion and interface advection by an external velocity field. The interface evolution equation is solved nume...

The dynamics of compressible liquid-vapor flow depends sensitively on the microscale behavior at phase boundary. We consider a sharp-interface approach, and propose multiscale model to describe accurately, without imposing ad-hoc closure relations continuum scale. combines Euler equations scale with molecular-scale particle simulations that govern interface motion. rely an interface-preserving ...