Publications/Reports

Publications
  1. M.T. Elenius, K. Johannsen, On the time scales of nonlinear instability in miscible displacement porous media flow, Computational Geosciences 16:  901-911; Sep 2012.
  2. K. Johannsen, A. Kopp, O. Tourunen,  J. Kleist, Studying CO2 Sequestration with the Power of Supercomputing. European Research Consortium for Informatics and Mathematics (ERCIM) 74 (2008) 17-18.
  3. A. Sapronova, K. Johannsen, Molecular dynamics study of natural gas hydrate kinetics in presence of KHI, Proceedings of the 6th International Conference on Gas Hydrates (ICGH 2008), Vancouver, British Columbia, CANADA, July 6-10, 2008.
  4. H.M. Nick, R. Schotting, M. Gutierrez-Neri, K. Johannsen, Modeling transverse dispersion and variable density flow in porous media, Transport in Porous Media, DOI 10.1007/s11242-008-9277-x, ISSN 0169-3913, 2008.
  5. A.J. Landman, K. Johannsen, R. Schotting, Density-dependent dispersion in heterogeneous porous media I: A numerical study, Advances in Water Resources, Volume 30, Issue 12, pp. 2467- 2480, 2007.
  6. K. Johannsen, Multilevel Methods for Nonsymmetric Discontinuous Galerkin Methods, Proceedings of the 20th Nordic Seminar on Computational Mechanics NSCM20, Gothenburg, December 2007.
  7. K. Johannsen, S. Oswald, R. Held, W. Kinzelbach, Numerical simulation of three-dimensional saltwater-freshwater fingering instabilities observed in a porous medium, Advances in Water Resources, 29(11): 1690-1704; Nov 2006.
  8. K. Johannsen, Numerical Aspects of Density Driven Flow in Porous Media, Proceedings of the CMWR XVI, Copenhagen, Denmark, June 19-22, 2006.
  9. K. Johannsen, A robust 9-point ILU smoother for anisotropic problems, IWR Preprint, University of Heidelberg, 2005/10.
  10. K. Johannsen, Multigrid Methods for NIPG, ICES Report 05-31, University of Texas at Austin, 2005.
  11. K. Johannsen, A Symmetric Smoother for the Nonsymmetric Interior Penalty Discontinuous Galerkin Discretization, ICES Report 05-23, University of Texas at Austin, 2005.
  12. K. Johannsen, G.Wittum, A SOR-type smoother for strongly non-symmetric positive definite matrices, sor.pdf. Unpublished.
  13. K. Johannsen, Numerische Aspekte dichtegetriebener Strömung in porösen Medien, professorial dissertation (habilitation), 2004.
  14. K. Johannsen, On the validity of the Boussinesq approximation for the Elder problem, Computational Geosciences 7(3): 169-182; Jan 2003.
  15. E. Oswald, K. Johannsen, W. Huang, The importance of dispersive mixing for modeling of density-dependent and reactive transport, in Computational Methods in Water Resources, S.M. Hassanizadeh et. al. (eds), 47(1), pp. 501-506, 2002.
  16. K. Johannsen, The Elder Problem - Bifurcations and steady state solutions, in Computational Methods in Water Resources, S.M. Hassanizadeh et. al. (eds), 47(1), pp. 485-492, 2002.
  17. K. Johannsen, W. Kinzelbach, S. Oswald, G. Wittum, The saltpool benchmark problem - numerical simulation of saltwater upconing in a porous medium, Advances in Water Resources, 25(3), pp. 335-348, 2002.
  18. P. Bastian, K. Johannsen, S. Lang, V. Reichenberger, C. Wieners, G. Wittum, Advances in High-performance Computing: High-accuracy simulation of density driven flow in porous media in: High Performance Computing in Science and Engineering, E. Krause, W. J¨ager, (eds), Springer, 2001.
  19. K. Johannsen, Perl Primer (german), Supplemental material for the lecture Introduction to Scientific Computing, summer term 2001, University of Heidelberg.
  20. K. Johannsen, Introduction to Scientific Computing (german), Lecture notes, summer term 2001, University of Heidelberg.
  21. K. Johannsen, The 2D-Saltpool Problem. 2000. Unpublished.
  22. P. Bastian, K. Johannsen, S. Lang, S. N¨agele, V. Reichenberger, C. Wieners, G. Wittum, C. Wrobel, Advances in High-performance Computing: Multigrid Methods for Partial Differential Equations and its Applications in: High Performance Computing in Science and Engineering, E. Krause, W. J¨ager, (eds), Springer, 506-519, 2000.
  23. K. Johannsen, Robust Smoothers for Convection-Diffusion Problems with Closed Characteristics, Computing, 65: 203-225, 2000.
  24. K. Johannsen, H. Gernert, W. Juling, G. Wittum, Numerische Simulation dichtegetriebener Strömung in porösen Medien, in: RZ-News des Rechenzentrums der Universität Karlsruhe, Nummer 2000/9, 10, ISSN 1432-7015.
  25. K. Johannsen, Robuste Mehrgitterverfahren für die Konvektions-Diffusions-Gleichung mit wirbelbehafteter Konvektion, Teubner 2000, ISBN: 3-519-02747-X.
  26. P. Bastian, K. Johannsen, and V. Reichenberger, UG Tutorial, 1999.
  27. K. Johannsen, Robuste Mehrgitterverfahren für die Konvektions-Diffusions-Gleichung mit wirbelbehafteter Konvektion, PhD-thesis, University of Heidelberg, 1999.
  28. P. Bastian, K. Birken, K. Johannsen, S. Lang, V. Reichenberger, C. Wieners, G. Wittum, C. Wrobel, A parallel software-platform for solving problems of partial differential equations using unstructured grids and adaptive multigrid methods, in: High Performance Computing in Science and Engineering, E. Krause W. Jäger (eds), Springer, 326-339, 1999.
  29. P. Bastian, K. Johannsen, B. Huurdeman, Parallel adaptive solution techniques for groundwater flow problems, Proceedings of the SIAM Conference on Parallel Processing, San Antonio, 1999.
  30. Fein (ed), d3f - Ein Programmpaket zur Modellierung von Dichteströmungen, GRS, Braunschweig, GRS-139, ISBN 3-923875-97-5, 1998.
  31. P. Bastian, K. Birken, K. Johannsen, S. Lang, N. Neuss, H. Rentz-Reichert, and C. Wieners, Parallel unstructured grid computations, In W. Hackbusch, editor, Proceedings of the 14th GAMM Seminar Kiel, Notes on Numerical Fluid Mechanics. Vieweg, 1998.
  32. K. Johannsen, An Aligned 3D-Finite-Volume Method for Convection-Diffusion Problems, in Modeling and Computation in Environmental Sciences, R. Helmig, W. Jäger, W. Kinzelbach, P. Knabner, G. Wittum (eds), Vieweg, Braunschweig, 59:227-243, 1997.
  33. K. Johannsen, Aligned 3D-Finite-Volumes for convection-diffusion problems, in: Finite Volumes for Complex Applications, F. Benkhaldoun, R. Vilsmeier (eds), Hermes, Paris, 291-300, 1996.
  34. P. Bastian, K. Birken, K. Johannsen, S. Lang, K. Eckstein, N. Neuss, H. Rentz-Reichert, C. Wieners, UG - A Flexible Software Toolbox for Solving Partial Differential Equations, Computing and Visualization in Science, 1:27-40, 1997.
  35. K. Johannsen, A Mathematical Description of (Open) Loudspeaker-Boxes, Preprint 93-23, University of Heidelberg, 1993.
  36. K. Johannsen, Teilchenaspekte im Schroermodell, master-thesis, Hamburg University, 1991.
Reports
  1. K. Johannsen, Geological Storage of CO2: Mathematical Modeling and Risk Assessment, Report, March 2009.
  2. K. Johannsen, An Algebraic Multigrid Method for the Stokes Equations, Report, December, 2008.