VolumeTracker and SurfaceTracker plugins

Related: Global Volume and Surface Constraints

These two plugins monitor the lattice and update the volume and surface of the cells once a pixel copy occurs. In most cases, users will not call those plugins directly. They will be called automatically when either Volume (together with VolumeTracker) or Surface or CenterOfMass (calls VolumeTracker) plugins are requested. However, one should be aware that in some situations, for example when doing foam coarsening, where neither Volume nor Surface plugins are called, one may still want to track changes in surface or volume of cells. In such situations, we explicitly invoke the VolumeTracker or Surface plugins with the following syntax:

<Plugin Name="VolumeTracker"/>

As of version 4.6.0, all you have to do to the Surface plugin to enable this behavior is add NeighborOrder.

<Plugin Name="Surface">
    <TargetSurface>120</TargetSurface>
    <LambdaSurface>0.5</LambdaSurface>
    <NeighborOrder>4</NeighborOrder>
</Plugin>

This will enable you to access the current volume and surface in Python with cell.volume and cell.surface.

Note

Legacy Version (Pre 4.6.0)

Previously, this arrangement of plugins was required. SurfaceTracker is now deprecated.

<Plugin Name="SurfaceTracker">
    <NeighborOrder>4</NeighborOrder>
</Plugin>

<Plugin Name="Surface">
    <TargetSurface>120</TargetSurface>
    <LambdaSurface>0.5</LambdaSurface>
</Plugin>