Effect of Scale on NaCl Dispersivity by HYDRUS 2D

آب و خاک

Article 16, Volume 27, Issue 4, September 2013, Pages 823-831   

Document Type: Research Article

DOI: 10.22067/jsw.v0i0.28204

Authors

M. Farasati^* ; S.M. Seyedian

Abstract

Dispersivity is an important property of a porous medium and Advection-Dispersion equation (ADE). It is used in solving problems related to pollutants migration by groundwater. Numerical models are frequently used for simulation of water movement in soils. In the present study, the dependence of NaCl dispersivity on thickness of the aquifer materials has been investigated. In orther to perform it, 5 different thickness of soil column (20, 40, 60, 80 and 100 cm) selected. The physical model used in the study consisted of a cylindrical tank with inner diameter of 6cm and 5 thicknesses 20, 40, 60, 80 and 100 cm of soil column designated by T1, T2, T3, T4 and T5 respectively. Sodium chloride with an electrical conductivity (EC) of 3 dSm-1 was selected as conservative pollutant. For calculation of dispersivity Brigham model and for simulation of NaCl movement HYDRUS software used. Results of the study indicated that the dispersivity of sandy porous was not dependent on the thickness. The result of HYDRUS showed that with increase of aquifer length, dispersivity increased but it was not significant.

Keywords

Dispersivity; Soil thickness; HYDRUS; Brigham model; NaCl