SoilVision Systems Ltd. is pleased to announce the addition of internal boundary conditions which can be used to represent geomembrane materials. The new feature was implemented in response to requests from customers and represents a significant improvement for the numerical modeling of a number of different scenarios involving geomembranes. More specifically, the geomembrane internal boundary condition is ideal for the modeling of containment ponds, landfills, mine tailings areas, and cover designs which include geomembranes.
Geomembranes typically have a low permeability relative to the surrounding earth material. Flow across these geomembranes over wide areas or over long times can be significant and often must be accounted for in a numerical model.
Geomembranes can also be modeled in SVFlux by defining a thin region and assigning a material to it with the properties of a geomembrane, but by using the Geomembrane boundary condition it is possible to realize significant solution time savings due to the decrease in required nodes.
Geomembrane boundary conditions are available for 1D, 2D, and 3D models. In 3D models, a geomembrane could be applied to a region sidewall to simulate a cutoff wall. The geomembrane boundary condition can also be applied to a 3D surface. In 3D models, the solver cannot currently handle automatic mesh refinement when this type of boundary condition is used. It will be turned off when the model is analyzed.
Geomembranes are applied as a regular internal boundary condition through the new 'Geomembrane' boundary condition specifier. They may only be specified on an internal boundary. The additional rules for their application may be found in the SVOffice 2009 User's Manual and the SVFlux Theory Manual.
Documentation for this feature is available in our online help. Use the search to locate the 'SVFlux Boundary Condition Types' section and scroll down to the Geomembrane section near the bottom.