2D Particle Tracking Under Radial Flow in Heterogeneous Media Conditioned at the Well

Abstract

The tracer test is one of the few experimental tools capable of estimating transport parameters at the local scale. Models used to estimate transport parameters (such as dispersivity) generally assume a homogeneous conductivity field. However, the distribution of the solute plume in heterogeneous media is primarily determined by the statistical nature of the hydraulic conductivity at the scale of the plume. We numerically simulate 2D transport of particles introduced into a steady injection well with prescribed head boundary conditions at the wellbore and at an exterior circle. We compute the travel time distribution of particles introduced into the well to points along a control circle of a given radius within a single transmissivity realization. In particular, we look at the effect of high, low, or average local wellbore transmissivity (as compared to the mean transmissivity of the domain) on the travel time distribution of each realization. We conclude that the difference between the logtransmissivity at the wellbore and the domain average logtransmissivity is likely to play an important role in the interpretation of dispersivity from conventional tracer tests.