Hierarchical Refinement for the Finite Element Solution of Cahn-Hilliard/Navier-Stokes Equations

Titre du congrès :Trends in Numerical and Physical Modeling for industrial Multiphase flow Ville du congrès :Cargèse Date du congrès :17/09/2007

  During an hypothetical major accident in a nuclear reactor, the degradation of the core may produce multiphase flows where interfaces undergo extreme topological changes, eg breakup and coalescence. Because of their ability to capture interfaces implicitly, phase field models are attractive for the numerical simulation of such phenomena [1]. They replace sharp interfaces by thin but nonzero thickness transition regions where capillary effects and changes in fluid properties are smoothed. The implied burden on the numerical method lies in the required resolution of very thin moving internal layers. We present here a finite element approximation of the Cahn-Hilliard/Navier-Stokes (CH/NS) equations which addresses this issue through an adaptive refinement strategy.