Panel A is a depiction of the physical system and the concentration profile along the x-axis at time less than zero. The concentration is zero everywhere. An injection supply is depicted by the small reservoir and the injection path into the aquifer (or stream). The valve is closed in this panel.
Panel B is a depection of the physical system and the concentration profile along the x-axis at time equal zero (like the Big Bang!). At t=0, mass is added into the aquifer (stream) at a rate CoQ at the origin (x=0). This mass flow rate at the injection site is maintained from t=0 onward.
Panel C is a depiction of the physical system and the concentration profile along the x-axis at some time greater than zero. The concentration front translates to the right of the origin a distance determined by the species velocity and dispersed along the front proportional to the dispersivity in the system. Some mass diffuses upstream from the injection site.
The analytical solution (Sauty) is
The solution is applicable for porous media flow, where the velocity (below) is the mean section velocity (seepage velocity divided by the porosity). The solution can also be used with streams and pipes (porosity = 1). Negative values of distance are not plotted in this interface, but the computed value at the point is correct.
Detailed Explaination (Under Construction)