coupling of free and porous-media flow
Understanding the coupled exchange processes between a free flow and flow through a porous medium is important for a wide spectrum of applications in many fields of research. Possible applications arise from environmental science, medical science, aerospace engineering, civil engineering, process engineering, energy supply, safety issues, and technical design problems. A common feature in all these applications is the interface between the free-flow and the porous-medium flow domain. In the vicinity of this interface, processes in both domains control the coupled exchange fluxes. Therefore, modeling the interface region is a key challenge and requires the consideration of various processes on different scales with varying physical complexity, and thus the application of adequate modeling strategies.
We will explain a newly developed model concept for multi-phase porous-medium flow coupled to a turbulent free flow, both including multi-component and energy transport. It is aimed to show an REV-scale two-domain concept which can handle two models in two separated subdomains and to couple them via appropriate coupling conditions at a sharp interface. One goal is to perform this coupling without introducing additional degrees of freedom on the interface. An existing porous-medium model, using the equations by Darcy or Forchheimer and discretized with the cell-centered finite volume method, is coupled to a (Reynolds-Averaged) Navier-Stokes model discretized with a marker-and-cell scheme (also known as staggered grid). Simulation results for the analysis of different model concepts, parameters, and setups will be presented.