B [±] deformation factor cL [eq(H )/l] H ion exchange capacity related to catalyst volume ct [mol/l] total molar concentration Deff [m /s] effective transport coefficient D [m/s] transport coefficient in gel phase or liquid phase ÐDij [m /s] binary Maxwell-Stefan diffusion coefficient of pair i-j m1 [±] volumetric distribution ratio of component 1 N [±] number of components N1 [mol/(m 2 s)] mol...

A lattice Boltzmann scheme is developed for homogeneous mixture modeling, based on the multiple-relaxation-time (MRT) formulation, which fully recovers the Maxwell-Stefan diffusion model in the continuum limit with (a) external force and (b) tunable Schmidt number. The theoretical basis of the proposed MRT formulation is a recently proposed Bhatnagar-Gross-Krook-type kinetic model for gas mixtu...

The transport of three gas species, O2, H2O and N2, through the cathode of a proton exchange membrane (PEM) fuel cell is studied numerically. The diffusion of the individual species is modeled via the Maxwell–Stefan equations, coupled with appropriate conservation equations. Two mechanisms are assumed for the internal energy sources in the system: a volumetric heat source due to the electrical ...

we introduce and discuss the homotopy perturbation method, the adomian decomposition method and the variational iteration method for solving the stefan problem with kinetics. then, we give an example of the stefan problem with  kinetics and solve it by these methods.

Stochastic unification-based grammars (SUBGs) define exponential distributions over the parses generated by a unificationbased grammar (UBG). Existing algorithms for parsing and estimation require the enumeration of all of the parses of a string in order to determine the most likely one, or in order to calculate the statistics needed to estimate a grammar from a training corpus. This paper desc...

We have used the Maxwell–Stefan diffusion theory to model mass transfer between tertiary-injected gas and residual oil blocked by water, in order predict time required for rupture of water barrier due swelling. also designed conducted a set visualization micromodel experiments on various pure multicomponent oil–gas systems measure tertiary injection processes. The experimental results show that...

Abstract An implicit Euler finite-volume scheme for general cross-diffusion systems with volume-filling constraints is proposed and analyzed. The diffusion matrix may be nonsymmetric not positive semidefinite, but the system assumed to possess a formal gradient-flow structure that yields $L^\infty $ bounds on continuous level. Examples include Maxwell–Stefan gas mixtures, tumor-growth models fa...