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8.2.3 Free Surfaces: Marker-and-Cell Method (MAC)
Introduce appropriate boundary conditions to handle such an open surface:
``marker'' particles distinguish between liquid-filled and empty Euler
cells.
The hydrodynamic equations with gravity,
are integrated by any of the foregoing techniques (usually the pressure
method). The marker particles in each cell move along according to
, where
is a particle velocity calculated by
interpolation (with suitable weights) from the velocities
in the adjacent Euler cells [HARLOW 65].
Treatment of boundary cells:
Four possible types - see Figure 8.2 for the respective
velocity boundary conditions. The pressure boundary conditions
are the same in all cases: , where is the
``external'' pressure in the empty Euler cells.
Figure 8.2:
MAC method: the 4 types of surface cells and the
appropriate boundary conditions for
(see [POTTER 80]).
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Next: 8.3 Lattice Gas Models
Up: 8.2 Incompressible Flow with
Previous: 8.2.2 Pressure Method
Franz J. Vesely Oct 2005
See also: "Computational Physics - An Introduction," Kluwer-Plenum 2001