Author(s): E. Helmut

Linked Author(s):

Keywords: No Keywords

Abstract: The paper describes a systematic experimental and numerical investi gation which explores the transverse vertical mixing across an initially sharp density interface between water containing salt (or high contaminant concentration) and fresh water in a porous medium under nearly horizontal flow conditions. The transversal spreading tendency due to the pore matrix is decreasing with increasing density difference due to gravity action. For a sand of uniform grain size and for a sand with a pronounced grain size distribution, systematic experiments and numerical calculations have been carried out in order to quantify the effects of density differences upon the transverse dis persion coefficient. It was found that in a uniform sand the mixing characteristics are essentially unaffected, whereas the sand mixture exhibits a significant density effect. From an analysis, an approximate relationship for the dispersion coefficient has been derived. The results indicate that density effects on transverse dispersion may be even more pronounced in natural aquifers with smaller velocities and larger inhomogeneities.

DOI:

Year: 1985