Stokes number attainable by dust grains at r = 1 AU (left panel) and r = 5 AU (right panel). Owing to the fragmentation barrier, solid grains within the disk cannot grow to an arbitrarily large size and disk turbulence acts as a limiting mechanism for particle growth. The inner regions of the disk are characterized by Stokes numbers on the order of St ~ 10⁻⁴, indicating very tight gas-dust coupling. Conversely, icy grains within the outer disk can reach Stokes numbers of order St ~ 10⁻¹, implying diminished aerodynamic drag.