New Approach for Approximation of Dispersivity in Porous Media

Journal of Structural Engineering and Geo-Techniques

مقاله 1، دوره 6، شماره 2، آذر 2016، صفحه 1-8   

نویسندگان

Mohammad Reza Fadaei Tehrani^{* 1}؛ Raheleh Feizy²؛ Homayoun Jahanian³

¹Research Assistant in Isfahan Higher Education and Research Institute (IHEARI), Isfahan, Iran

²Science and Research Branch, Islamic Azad University, Tehran, Iran

³Department of civil engineering, college of Civil engineering & Surveying, Qazvin Branch, Islamic Azad Universiry, Qazvin, Iran

چکیده

This paper presents a simple yet powerful original approach for approximating dispersivity in porous media. The key to this approach is both use of least-squares criterion and image processing technique. Two dimensional transparent models, including horizontal and vertical configurations, under different combinations of grain sizes and pore velocities, experimented. Concentration data were obtained on a 0.5×0.5 mm grid, which represents approximately 1.8×10⁵ measuring points. Estimates of the longitudinal and transverse dispersivity are obtained for each experiment in three time step, and discussed. Acquired results revealed that presented procedure successfully determine dispersivity coefficients and the maximum error of estimation is 4 to 7%. Furthermore, calculated disperssivity varied from 0.001 to 0.003 m corresponding to grain sizes that agree with literature.

کلیدواژه‌ها

disperssivity؛ dispersion؛ porous media؛ least-squares criterion؛ Image processing