Numerical solution of the Navier-Stokes equations for incompressible flow in porous media with free surface boundary

The paper presents numerical solution of the three dimensional Navier-Stokes equations for complex flow domains consisting of fluid and porous regions with free surface boundary. Flow in both regions is described by single set of conservation equations, extending the momentum equation for porous regions by additional viscous drag term according Darcy law. Free surface kinematics is “tracked” by Volume of Fluid method. Firstly the model is verified by comparision with numerical solution of Laplace equation for simple free surface flow through vertical dam. Good result agreements are observed. Application on realistic problems is presented on two cases. First case considers problem of pressure redistribution process around a deep tunnel excavation in low-conductivity porous media and second considers flow under and through porous, partially submerged bridge.