摘要:An Arbitrary Lagrangian-Eulerian (ALE) level-set method to solve incompressible
two-dimensional two-fluid flows is presented. The Navier-Stokes equations are
discretized by a Galerkin Finite Element method. A projection method based on
approximated LU decomposi- tion is employed to decouple the system of non-linear
equations. The interface between fluids is represented by a discrete Heaviside
function plus additional marker points and edges of the computational mesh. Our
method employs a technique which moves the nodes of the Finite Element mesh with
arbitrary velocity. The quality of the mesh is controlled by a remeshing
procedure, avoiding bad triangles by flipping edges, inserting or removing
vertices from the triangulation. The relative velocity in the ALE approach is
designed to allow for a continuous improvement of the mesh, thus reducing the
amount of remeshing required to control the quality of the mesh. Results of
numerical simulations are presented, illustrating the improvements in
computational cost, mass conservation, and accuracy of this new methodology.