Solution of the Transient Gas-Phase Diffusion Problem Equations 11.4 to

APPENDIX 11 SOLUTION OF THE TRANSIENT GAS-PHASE DIFFUSION PROBLEM EQUATIONS (11.4) TO (11.7) 

We can solve this problem by Laplace or similarity transforms. Let us use the latter. Let 

Then the total quantity of A that has been transferred into the particle from r = 0 to / is 

Bhatnagar, P. L., Gross, E. P, and Krook, M. (1954) A model for collision processes in gases. 1. Small amplitude processes in charged and neutral one-component systems, Phys. Rev., 94, 511-525. 

Stewart, W. E., and Lightfoot, E. N. (1960) Transport Phenomena. Wiley, New York. 

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