2017 Volume 73 Issue 2 Pages I_85-I_96
Intermediate-scale laboratory solute transport experiments are conducted in heterogeneous porous formations comprised by 24 × 16 sand cells in a 100 × 80 × 3 cm sandbox. The spatial distributions of hydraulic conductivity having different values of the correlation length are geostatistically generated. Visualization of dye solute is applied to transitional estimates in longitudinal and transverse macrodispersivities caused by the presence of heterogeneities. Experimental results reveal that the longitudinal and transverse macrodispersivities show the dependence and non-dependence nature on the correlation length, respectively. Laboratory study is extended by a random walk particle tracking approach to reconstruct the estimated macrodispersivity transition, demonstrating a good agreement between the experimental and numerical results. A highlight of our experimental approach is that the variations of the ratio of the longitudinal macrodispersivity to the correlation length exhibit almost the same evolution despite of the correlation length. Quantification imaging methodology is proposed to investigate the relation between the apparent heterogeneity and the macrodispersivities based on solute distributions.
