Left panel: comparison of the gas radial velocity obtained by hydrodynamical simulations using FARGO for q = 1 × 10^-3, H/r = h₀r^f with h₀ = 0.05 and f = 0.25, and α = 10^-3, when ν_r,d is calculated from viscous accretion (Eq. (5)), assuming Σ by azimuthally averaging the gas surface density from FARGO simulations, and when the gas surface density is calculated analytically (Sect. 2.1) and ν_r,d from Eq. (5). Other panels: dust density distribution at the same time of evolution (~ 1 Myr) for the same assumptions. White line corresponds to St = 1 (Eq. (3)), which is proportional to the gas surface density.