Dr.-Ing. Niklas Fehn

Contact

  • Room 1236
  • Email: niklas.fehn@tum.de
  • Phone: +49 (0) 89 289 15237
  • Fax:     +49 (0) 89 289 15301

Education

  • since 2021 Postdoctoral Researcher at the Institute for Computational Mechanics (Lehrstuhl für Numerische Mechanik), Technical University of Munich, Germany
  • 2021 Doktoringenieur (Dr.-Ing.), Mechanical Engineering, Technical University of Munich, Germany
  • 2016-2021 Research Associate at the Institute for Computational Mechanics (Lehrstuhl für Numerische Mechanik), Technical University of Munich, Germany
  • 2015 Master of Science (M.Sc.), Mechanical Engineering, Technical University of Munich, Germany

Research interests

Software projects

PhD Thesis

Peer-reviewed articles in international journals, proceedings, book contributions, conference contributions

  • J. Nitzler, J. Biehler, N. Fehn, P.-S. Koutsourelakis, W. A. Wall, A Generalized Probabilistic Learning Approach for Multi-Fidelity Uncertainty Propagation in Complex Physical Simulations, Computer Methods in Applied Mechanics and Engineering, 400, 115600, 2022. DOI
  • N. Fehn, M. Kronbichler, P. Munch, W. A. Wall, Numerical evidence of anomalous energy dissipation in incompressible Euler flows: Towards grid-converged results for the inviscid Taylor-Green problem, Journal of Fluid Mechanics 932, A40, 2022. DOI
  • M. Kronbichler, N. Fehn, P. Munch, M. Bergbauer, K. Wichmann, C. Geitner, M. Allalen, M. Schulz, W. A. Wall, A next-generation discontinuous Galerkin fluid dynamics solver with application to high-resolution lung airflow simulations, Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis (SC21), Article No 21, 1-15, 2021. DOI
  • N. Fehn, J. Heinz, W. A. Wall, M. Kronbichler, High-order arbitrary Lagrangian-Eulerian discontinuous Galerkin methods for the incompressible Navier-Stokes equations, Journal of Computational Physics 430, 110040, 2021. DOI
  • N. Fehn, P. Munch, W. A. Wall, M. Kronbichler, Hybrid multigrid methods for high-order discontinuous Galerkin discretizations, Journal of Computational Physics 415, 109538, 2020. DOI
  • D. Arndt, N. Fehn, G. Kanschat, K. Kormann, M. Kronbichler, P. Munch, W. A. Wall, J. Witte, ExaDG: High-Order Discontinuous Galerkin for the Exa-Scale, In H.-J. Bungartz, S. Reiz, B. Uekermann, P. Neumann, and W. E. Nagel (eds.), Software for Exascsale Computing - SPPEXA 2016-2019, pages 189-224, Cham, 2020, Springer International Publishing. DOI
  • M. Kronbichler, K. Kormann, N. Fehn, P. Munch, J. Witte, A Hermite-like basis for faster matrix-free evaluation of interior penalty discontinuous Galerkin operators, submitted. PDF
  • N. Fehn, M. Kronbichler, C. Lehrenfeld, G. Lube, P. W. Schroeder, High-order DG solvers for under-resolved turbulent incompressible flows: A comparison of L2 and H(div) methods. International Journal for Numerical Methods in Fluids 91 (11), 533– 556, 2019. DOI
  • N. Fehn, W. A. Wall, M. Kronbichler, Modern discontinuous Galerkin methods for the simulation of transitional and turbulent flows in biomedical engineering: A comprehensive LES study of the FDA benchmark nozzle model, International Journal for Numerical Methods in Biomedical Engineering 35 (12), e3228, 2019. DOI
  • N. Fehn, W. A. Wall, M. Kronbichler, A matrix-free high-order discontinuous Galerkin compressible Navier-Stokes solver: A performance comparison of compressible and incompressible formulations for turbulent incompressible flows, International Journal for Numerical Methods in Fluids 89 (3), 71-102, 2019. DOI
  • N. Fehn, W. A. Wall, M. Kronbichler, Efficiency of high-performance discontinuous Galerkin spectral element methods for under-resolved turbulent incompressible flows, International Journal for Numerical Methods in Fluids 88 (1), 32–54, 2018. DOI
  • N. Fehn, W. A. Wall, M. Kronbichler, Robust and efficient discontinuous Galerkin methods for under-resolved turbulent incompressible flows, Journal of Computational Physics 372, 667-693, 2018. DOI
  • N. Fehn, W. A. Wall, M. Kronbichler, On the stability of projection methods for the incompressible Navier–Stokes equations based on high-order discontinuous Galerkin discretizations, Journal of Computational Physics 351, 392-421, 2017. DOI
  • B. Krank, N. Fehn, W. A. Wall, M. Kronbichler, A high-order semi-explicit discontinuous Galerkin solver for 3D incompressible flow with application to DNS and LES of turbulent channel flow, Journal of Computational Physics 348, 634-659, 2017. DOI
  • M. Kronbichler, B. Krank, N. Fehn, S. Legat, W. A. Wall, A new high-order discontinuous Galerkin solver for DNS and LES of turbulent incompressible flow, in: New Results in Numerical and Experimental Fluid Mechanics XI pp. 467-477, 2018, contributions to the 20th STAB/DGLR Symposium, Braunschweig, November 8-9, 2016. DOI

International conference contributions with abstract

  • N. Fehn, M. Kronbichler, P. Munch, W. A. Wall, On numerical evidence of anomalous energy dissipation, 14th European Fluid Mechanics Conference (EFMC14), Athens, Greece, September 13 - 16, 2022. Abstract
  • P. Münch, N. Fehn, W. A. Wall, M. Kronbichler, SIMD vectorization for high-order matrix-free finite element computations in CFD, SIAM Conference on Computational Science and Engineering (CSE19), Spokane, Washington, USA, February 25 - March 1, 2019. Abstract
  • N. Fehn, W. A. Wall, M. Kronbichler, Efficient matrix-free DG solvers for the incompressible Navier-Stokes equations, SIAM Conference on Computational Science and Engineering (CSE19), Spokane, Washington, USA, February 25 - March 1, 2019. Abstract
  • N. Fehn, W. A. Wall, M. Kronbichler, Efficient discontinuous Galerkin methods for under-resolved turbulent incompressible flows, 7th European Conference on Computational Fluid Dynamics, Glasgow, UK, June 11-15, 2018. Abstract

Presentations and invited talks

  • N. Fehn, G. Kanschat, K. Kormann, M. Kronbichler, W. A. Wall, J. Witte, ExaDG: High-Order Disontinuous Galerkin for the Exa-Scale, talk at SPPEXA Annual Plenary Meeting, Munich, Germany, January 23, 2019
  • N. Fehn, M. Kronbichler, High-order discontinuous Galerkin solvers for incompressible flows based on a high-performance, matrix-free implementation, invited seminar talk at Vienna University of Technology, Vienna, Austria, October 12, 2017
  • N. Fehn, W. A. Wall, M. Kronbichler, High-order discontinuous Galerkin solvers for incompressible flows based on a high-performance, matrix-free implementation, talk at workshop on Fast high order DG methods for future architectures, Heidelberg, Germany, July 3-5, 2017

Supervised student projects

  • Patient-specific assessment of high-risk locations for atherosclerosis in coronary arteries using a novel discontinuous Galerkin fluid dynamics solver, Term Paper, Caroline Gramm, 2022
  • High-performance implementation of H(div)-conforming elements for incompressible flows, Master's Thesis, Niklas Wik, 2022
  • Simulation of aeroacoustic problems with discontinuous Galerkin FEM, Term Paper, Anian Fuchs, 2020
  • Computational Fluid Dynamics Simulation of an Endotracheal Tube Using a High-Order Discontinuous Galerkin Turbulent Flow Solver and Patient-Specific Settings, Bachelor's Thesis, Xuhui Zhang, 2019
  • High-Order Discontinuous Galerkin Methods on Moving Meshes for the Incompressible Navier-Stokes Equations, Master's Thesis, Johannes Heinz, 2019
  • Numerical Investigations on the Efficiency of an In-House High-Order Discontinuous Galerkin Flow Solver Compared to OpenFOAM, Master's Thesis, Yingxian Wang, 2019
  • Advanced timestepping techniques for an incompressible Navier-Stokes solver with discontinuous Galerkin discretization, Term Paper, Leon Riccius, 2019
  • An efficient hybrid multigrid solver for high-order discontinuous Galerkin methods, Master's Thesis, Peter Münch, 2018
  • Analyse des spektralen Verhaltens von diskontinuierlichen Galerkin-Verfahren für turbulente Strömungen, Bachelor's Thesis, Oliver Neumann, 2018
  • Hermite-artige Basisfunktionen für diskontinuierliche Galerkin-Verfahren hoher Ordnung, Bachelor's Thesis, Anian Fuchs, 2017
  • A discontinuous Galerkin approach for the compressible Navier-Stokes equations, Master's Thesis, Christoph Haslinger, 2017
  • Turbulence modeling for large eddy simulation of incompressible flows using high-order discontinuous Galerkin methods, Bachelor's Thesis, Tim Dockhorn, 2017
  • Numerical analysis and comparison of high-performance, incompressible Navier-Stokes solvers based on the discontinuous Galerkin method, Master's Thesis, Shahbaz Haider, 2017