Time sequences of corundum density, corundum grain radius, silicate density, and silicate grain radius for slices through the center of model st28gm06n038 (rows 1–4). The dashed circle marks the estimated stellar radius of 478 R_⊙. The over-plotted contour in the corundum grain size panels (row 2) marks where silicate grains (row 4) have reached a radius of 0.2 μm, probably indicating the outer edge of the gravitationally bound dust layers (see text). Row 5 visualizes the dynamics with pseudo-streamlines (integrated over 10⁶ s; the colored lines indicate the radial ray used in Fig. 4). Shock fronts appear as regions where flows with different directions collide. The snapshots are about 2 months apart.