USE OF FINITE PROPAGATION VELOCITY IN THE SOLUTION OF INTERFACE MASS TRANSFER PROBLEMS

A number of theories have been proposed to explain and interpret mass transfer processes at interfaces. Most of these models are based on solutions of Fick's Law of diffusion to describe the transfer process. There are evidences, however, both experimental and theoretical, which show that this fundamental law has shortcomings. An objection to the classical error-function solution of the diffusion problem is the physically unrealistic predicted instantaneous response at every position in the system to a step change. In addition, mass transfer rate given by such a solution approaches infinity as time approaches zero. Inclusion of finite velocity of propagation in the governing differential equation overcomes both the theoretical objections to the classical solution. This concept is utilized in predicting the concentration profile and mass transfer rates in systems with zero and first order chemical reactions. 1984, Taylor & Francis Group, LLC. All rights reserved.

USE OF FINITE PROPAGATION VELOCITY IN THE SOLUTION OF INTERFACE MASS TRANSFER PROBLEMS Academic Article