Wolfgang Wendland

Mathematisches Institut A

University of Stuttgart

**Abstract:**
We develop a general phenomenological theory of
sedimentation-consolidation processes of flocculated suspensions, which
are considered as mixtures of two superimposed continuous media.
Following the standard approach of continuum mechanics, we derive a
mathematical model for these processes by applying constitutive
assumptions and a subsequent dimensional analysis to the mass and linear
momentum balance equations of the solid and liquid component. In two of
three space dimensions, solvability of the resulting equations depends
on the choice of phase and mixture viscosities. In one space dimension,
however, this model reduces to a quasilinear strongly degenerate
parabolic equation, for which analytical and numerical solutions are
available. The theory is applied to a batch sedimentation-consolidation
process.