MODELING CONVECTIVE WATER FLOW IN REPACKED SAND COLUMNS BY BREAKTHROUGH CURVES OF CHLORIDE

Öz

This paper describes a novel theory for modeling water flow in porous media, such as soils, using breakthrough curves of nonreactive chemicals. Miscible displacement tests of chloride were conducted in repacked sand columns (30.0 cm length and 8.0 cm id.) that were prepared using washed sand particles with diameters of 2.0-1.0, 1.0-0.5, 0.5-0.25, and <0.25 mm. Sands with different particle-size were used to evaluate the theory in different water flow regimes. The resultant BTCs of Cl were used to model the hydraulic conductivity as a function of mobile water content (K(qm)) of the sand columns. Laboratory measured and modeled values of saturated hydraulic conductivity (Ks) were compared to validate the model developed. Correlation analysis of the measured and approximated Ks values resulted in a correlation coefficient of r = 0.91 (P<0.001), suggesting that the model developed successfully utilized the data in BTCs to quantify the water flow in the sand columns evaluated in this study.

Anahtar Kelimeler

• Mobile water content, Hydraulic conductivity, Breakthrough curve, Chloride, Porous media, Water flow

S. ERŞAHİ 1,* T. AŞKI 2 C. TARAKÇIOĞLU2 D.B. ÖZE Ç2 K. KORKMAZ T. KUTLU3

Öz

Kaynakça

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