Dust Formation in Substellar Atmospheres: A Multi-Scale Problem

Abstract

The large scales of substellar atmospheres are determined by an interplay between convection, dust formation and gravitational settling. The consequence is an element depletion of the upper dust forming regions and an element enrichment of the dust evaporating sites. The formation of dust cloud structures in substellar atmospheres is investigated based on a consistent theoretical description of hydrodynamics, dust formation and destruction, gravitational settling, and element depletion including the effect of mixing by convective overshoot. Results of the calculation are, e.g., the mean size of the dust particles and the element depletion which both vary with atmospheric height.