The Simulated Calculation for Diffusion Process in Gas Detector

Concentration distribution expression of gas diffusion, reaction process at limited distance in small diameter pipe containing solids, the relation of gas concentration,diffusion time and diffusion distance have been derived by the second Fick's low.In the certain diffusion time the relation of gas concentration and diffusion depth is parabolic.The ratio of the square of certain concentration gas diffusion depth and diffusion time is constant when it diffuses and reacts through the solids bed.The theoretical analysis is in accordance with experimental results.