Density of the largest dust species (a = 189 nm) in a slice from the 3D simulation (z = 0.165 pc) at t = 0.0065 (6.36 × 10⁴ yr). Only a part of the simulated region with an extend of 0.138 pc in the x-direction is shown. Three distinct regions of dust density enhancement are indicated with labels 1, 2 and 3 discussed in the text. The velocity field of the largest dust species in the x − y plane is indicted with the use of vectors, the largest velocity are around 6 × 10⁵ cm s^-1.