Radial anomalous diffusion in an annulus
详细信息 查看全文
- 作者：Shaowei Wang<sup>asup><sup> ; sup><sup>shaoweiwang@126.com"" rel=""nofollowsup> ; Moli Zhao<sup>bsup> ; Xicheng Li<sup>csup>
- 关键词：Radial diffusion ; Fractional derivative ; Hankel transform ; Laplace transform ; Moment
- 刊名：Physica A
- 出版年：2011
- 出版时间：1 October 2011
- 年：2011
- 卷：390
- 期：20
- 页码：3397-3403
- 全文大小：255 K
文摘
In this study, time fractional radial diffusion has been modeled in cylindrical coordinates in order to analyze the anomalous diffusion in an annulus. By using an integral transform technique, the analytical solution of the concentration distribution formula is obtained. The establishing of the concentration distribution is found to be controlled by the fractional derivative α, and the influences of α on the concentration field, the total amount diffused and the quantity of mass passing through the inner wall are presented graphically and studied in detail. Asymptotic expressions for the exact solutions are developed in order to explain the numerical results at small and large time, respectively, and the physical mechanism explanation for the paradoxical behavior shown in the numerical results is given.