The Thin Barrier boundary condition models interior permeable walls, membranes, geotextiles, or perforated plates as thin permeable barriers. The Thin Barrier boundary condition can only be applied on interior boundaries.

Enter a value or expression for the Thickness db (SI unit: m, the default is 0.1 m) and for the Permeability κb (SI unit: m2). The default Permeability κb uses the value From material. For User defined select Isotropic to define a scalar value or Diagonal, Symmetric, or Full to define a tensor value and enter another value or expression in the field or matrix.