Open Access

ARTICLE

On the Behavior of an Interface under Molecular Diffusion: A Theoretical Prediction and Experimental Study

R. Abdeljabar¹

1 URME, National school of engineers of Tunis B.P37, 1002 Belvédère, Tunisia.ridha.abdeljabar@enit.rnu.tn

Fluid Dynamics & Materials Processing 2009, 5(2), 193-210. https://doi.org/10.3970/fdmp.2009.005.193

Abstract

A theoretical model has been developed to predict the expansion of a salty gradient (i.e. the interface) layer under natural diffusion. The salty gradient layer is initially sandwiched between two homogeneous miscible layers of varying salinity, which may or may not have the same thickness. The model describes the concentration profile of the salty gradient layer (expressed by analytical solutions of the diffusion equation) as the boundaries of this interfacial layer move into the adjacent (hitherto homogeneous) regions. The lifetime of the adjacent layers is also predicted. An experimental study for a configuration with salty water below and distilled water above (of the same thicknesses) is carried out to verify the theoretical predictions of the model.

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Keywords

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