Numerical analysis of the effects of local hydrodynamics on mass transfer in heterogeneous porous media

摘要

Many engineering problems require the estimation of mass transfer coefficients in porous materials.In heterogeneous materials or in cases where mass transfer sites are not spatially uniform,empirical equations for mass transfer coefficients vary widely,and the origin of these differences is not well understood.In this article,we use a stochastic algorithm to model mass transfer from sigle particles in a two-dimensional heterogeneous packed bed.The computed mass transfer coefficients are used to geneate a distribution of local Peclet numbers in the bed.Detailedhydrodynbamics are then used to interpret variations in the local Peclet number.The results show clear relationships between pore structure,streamline patterns,and mass transfer rates.