Influence of time factor on diffusion coefficient based on classical model

doi:10.16265/j.cnki.issn1003-3033.2020.02.010

Abstract

Abstract: In order to study influence of time factor on fitting and calculation of diffusion coefficient, theoretical error during fitting process was analyzed based on classical diffusion model. Then, variation trends of diffusion coefficient and determination coefficient R² over time were analyzed through conventional and fixed intercept linear methods with experimental data of gas diffusion dynamics in coal particles at different time periods and intervals. The results show that theoretical error of fitting decreases as diffusion time extends, and diffusion coefficient calculated by conventional fitting and fixed intercept fitting tends to be the same over time. However, it varies a lot with the increase of time period and interval and is affected by data at zero time.

Key words: gas diffusion coefficient, classical diffusion model, diffusion time, linear fitting, fixed intercept

CLC Number:

X936

ZHANG Xianshang. Influence of time factor on diffusion coefficient based on classical model[J]. China Safety Science Journal, 2020, 30(2): 60-65.

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