Non-Fickian diffusion in viscous aerosol particles

Slow condensed phase diffusion in organic aerosol particles can impede many chemical and physical processes associated with atmospheric (e.g., gas-particle equilibrium partitioning). The characteristic times these high viscosity are typically modelled using a concentration-dependent diffusivity within purely Fickian framework. In that model, the medium which is taking place treated as being inviscid far mass transport concerned. this report, we investigate validity of assuming equal to zero by model includes viscous pressure gradients. It found effect negligible for radii larger than 100 nm, but below radius, it delay water uptake loss orders magnitude physically realistic viscosities. However, if Stokes–Einstein relation obeyed, then be ignored, even nanosized particles. addition numerical calculations, dimensionless Deborah number defined indicates significance compared rheological response during transport.