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HYDRODYNAMIC DISPERSION IN POROUS MATERIALS

This paper considers some aspects of the hydrodynamic dispersion of tracer which occurs under the combined influence of molecular diffusion and convection when a fluid flows through a finite column of porous material. In particular, the paper discusses (i) the use of the principle of superposition to obtain breakthrough curves for pulsed and periodic inputs of trace, (ii) the form of dispersion coefficients in terms of dimensionless groups of parameters, and (iii) the mechanisms underlying dispersion.