ECCOMAS Thematic Conference on Multi-scale Computational Methods for Solids and Fluids A. Ibrahimbegovic, F. Dias, H. Matthies, P. Wriggers (eds.) Cachan, France, November 28-30, 2007 DUMUX: A MULTI-SCALE MULTI-PHYSICS TOOLBOX FOR FLOW AND TRANSPORT PROCESSES IN POROUS MEDIA Bernd Flemisch 1 , Jochen Fritz 1 , Rainer Helmig 1 , Jennifer Niessner 1 , and Barbara Wohlmuth 2 1 Institute of Hydraulic Engineering Universit¨ at Stuttgart Pfaffenwaldring 61 70569 Stuttgart, Germany e-mail: {flemisch,fritz,helmig,niessner}@iws.uni-stuttgart.de 2 Institute for Applied Analysis and Numerical Simulation Universit¨ at Stuttgart Pfaffenwaldring 57 70569 Stuttgart, Germany e-mail: wohlmuth@ians.uni-stuttgart.de Keywords: porous media, multi-phase multi-component flow, software, transport Abstract. Flow and transport processes in porous media occur on different spatial and tem- poral scales and may also exhibit different physical behavior in different parts of the model domain. Additionally, the structure of the porous medium itself generally shows a high depen- dence on the spatial scale. Employing a complex fine scale model throughout the whole domain is in general very expensive and often limited by the available computational resources. More- over, in many cases, it is not needed to use the full model everywhere, and one can choose a simpler one and/or consider one on a coarser scale in large parts of the domain. Our goal is to develop a multi-scale multi-physics toolbox DuMu x for nonisothermal compo- sitional multiphase flow and transport processes in porous media which makes use of the locally different behavior. In particular, we aim to use in each part of the domain the model which is the less expensive but still accurate enough to describe the physics correctly. Furthermore, we want to be able to choose the best discretization in space and time for each model. We use modern programming techniques within the framework of DUNE, the Distributed and Unified Numerics Environment which has been developed recently. It allows to implement the necessary numerical algorithms independent of the ultimately used data structures. This paper presents the current possibilities of our toolbox. 1