A MODEL FOR SOLUTE TRANSPORT FOLLOWING AN ABRUPT PRESSURE IMPACT IN SATURATED POROUS-MEDIA

A mathematical model is developed of an abrupt pressure impact applied to a compressible fluid with solute, flowing through saturated porous media. Nondimensional forms of the macroscopic balance equations of t he solute mass and of the fluid mass and momentum lead to dominant for ms of these equations. Following the onset of the pressure change, we focus on a sequence of the first two time intervals at which we obtain reduced forms of the balance equations. At the very first time period , pressure is proven to be distributed uniformly within the affected d omain, while solute remains unaffected. During the second time period, the momentum balance equation for the fluid conforms to a wave form, while the solute mass balance equation conforms to an equation of adve ctive transport. Fluid's nonlinear wave equation together with its mas s balance equation, are separately solved for pressure and velocity. T hese are then used for the solution of solute's advective transport eq uation. The 1-D case, conforms to a pressure wave equation, for the so lution of fluid's pressure and velocity. A 1-D analytical solution of the transport problem, associates these pressure and velocity with an exponential power which governs solute's motion along its path line.