A mass conserving level set (MCLS) method for modeling of multi-phase flows

The Mass-Conserving Level-Set (MCLS) method is proposed to model multi-phase flows. The aim is to model high density-ratio flows with complex interface topologies, such as mixtures of bubbles and droplets. Aspects which are taken into account are: a sharp front (density changes rapidly), arbitrary shaped interfaces, surface tension, buoyancy and co-alescence of drops/bubbles. Attention is paid to mass-conservation and integrity of the interface. A survey of available computational methods is performed in [1]. The proposed computational method is a combination of Level-Set and Volume-of-Fluid methods. The flow is computed with a pressure correction method with a Marker-and-Cell layout. Interface conditions are satised by means of the continuous surface force/stress (CSF/CSS) methodology and the GhostFluid method for incompressible flows. The Level-Set method is an elegant method. The major disadvantage is that it is not rigorously mass-conserving. This means that additional effort is necessary to conserve mass. The MCLS method introduces a Volume-of-Fluid function, which is advected without the necessity to reconstruct the interface. There is a strong relationship between the Volume-of-Fluid function and the Level-Set function. In the spirit of the Level-Set methodology, the advection of the VOF-function is, unlike other VOF methods, purely implicit at every time. This makes the method straightforward to apply to arbitrarily shaped interfaces, which may collide and break up.