ON DIFFUSION IN NANOSPACE
M.Kojic, M.Milosevic, N.Kojic, M.Ferrari, A.Ziemys UDC: (539.194)
Diffusion in nanospace does not strictly obey to Fick’s law generally used in macroenvironment. Deviation from this law is due to surface effects, i.e. due to interaction between transported molecules and bounding surfaces. A hierarchical modeling approach which accounts for interface effects on the diffusion coefficient was introduced in Ziemys et al. (2011). The model employs molecular dynamics (MD) for calculation scaling functions to reduce the diffusion coefficient corresponding to “bulk” values. With this reduced diffusion coefficient, modeling is performed using the finite element method (FE) within an incremental iterative scheme.
In this paper we summarize this hierarchical (multiscale) model and present its generalization to include adsorption at the walls. Also, we briefly discuss further possible applications of the multiscale modeling of diffusion through complex media with distributed solid constituents, as in case of polymers or biological fluids.