PDF of the dust density of the 1 nm (left) and 10 μm (middle). The colour coding indicates the dust fluid treatment (two fluid Lagrangian particles in blue, tracer particles in red, monofluid in black). For clarity, only the monofluid quantities of the 256_2F are shown. The solid lines show the results of the 256_2F run, while the dotted lines show the results of the 128_2F. Right: PDF of the adaptive length of the two-fluid dust Lagrangian-particle distributions (solid lines for the 10 μm dust grains, dotted line for the 1 nm) for the 256_2F (blue) and 128_2F (red) models. The vertical dashed lines indicate the grid numerical resolution (black for 256_2F, grey fro 128_2F).