Dust-to-gas density ratio at t = 100 T₀ from models with different numerical resolutions. The left and right columns correspond to models with α = 10⁻⁴ and 10⁻⁵, respectively. Middle row: Models with the fiducial resolution (i.e., ~200 cells per H_g in both directions). Top and bottom rows: Models with two times higher resolution than fiducial in the r direction (top) and θ direction (bottom).