EXPERIMENTAL INVESTIGATIONS ON SOLUTE DISPERSION IN DARCY AND NON-DARCY TRANSITION REGIONS

Abstract

 Column experiments with mixed various particle size distributions were conducted in order to elucidate the influence of physical and fluid properties such as particle size distribution, porosity and Reynolds and Peclet numbers on the solute spreading in Darcy and non-Darcy transition regions. Temporal moments based on breakthrough curves were utilized to estimate the “apparent dispersivity”. It was confirmed that the particle size distribution affected seepage flow regimes and subsequent apparent dispersivity estimates. In addition, linear multiple regression analysis using AIC was performed on physical and fluid properties that had a correlation with the apparent dispersivity. Furthermore, a new estimation function involving the uniformity coefficient and Reynolds and Peclet numbers associted with Darcy and non-Darcy flow regimes was proposed, resulting in a good agreement between experimental and estimated results.