Presentations

Conference Presentations

2023

  1. F. D. Witherden,
    On the Implementation of Small Dense Matrix Multiplications on Intel GPUs.
    CEED7AM, 1–3 August 2023, Livermore, California, USA.
  2. F. D. Witherden,
    Elements of Modern Computing Hardware for Computational Fluid Dynamics.
    55th Fluid Mechanics Lecture / 41st Aerospace Numerical Simulation Technology Symposium, 14 July 2023, Shibuya-ku, Tokyo, JP.
  3. T. Dzanic and F. D. Witherden,
    A Positivity-Preserving and Conservative High-Order Flux Reconstruction Method for the Polyatomic Boltzmann–BGK Equation.
    22nd IACM Computational Fluids Conference, 25–28 April 2023, Cannes, France.
  4. A. Akbarzadeh, M. Alhawwary, F. D. Witherden, and A. Jameson,
    Numerical prediction of drag crisis for smooth spheres using a high-order flux reconstruction method.
    AIAA Scitech 2023 Forum, 23--27 January 2023, National Harbor, Maryland, USA.
  5. R. Modi, M. Alhawwary, A. Akbarzadeh, F. D. Witherden, and A. Jameson,
    Aeroacoustics noise prediction for the airfoil-rod benchmark using high-order large eddy simulation on unstructured grids and the acoustic analogy approach in frequency-domain.
    AIAA Scitech 2023 Forum, 23--27 January 2023, National Harbor, Maryland, USA.

2022

  1. T. Dzanic and F. D. Witherden,
    A Positivity-Preserving and Conservative High-Order Flux Reconstruction Method for the Polyatomic Boltzmann–BGK Equation.
    5th Annual Meeting of the SIAM Texas-Louisiana Section, 4–6 November 2022, Houston, Texas, USA.
  2. F. D. Witherden,
    Exploiting Task Graphs for Fun and Strong Scaling.
    CEED6AM, 9–10 August 2022.
  3. T. Dzanic and F. D. Witherden,
    Utilizing Time-Reversibility for Shock Capturing in Nonlinear Hyperbolic Conservation Laws.
    WCCM-APCOM 2022, 31–5 August 2022, Yokohama, Japan.
  4. T. Dzanic and F. D. Witherden,
    Positivity-Preserving Entropy-Based Adaptive Filtering for Discontinuous Spectral Element Methods.
    ECCOMAS 2022, 5–9 June 2022, Oslo, Norway.

2021

  1. F. D. Witherden, S. Akkurt, and P. E. Vincent,
    Cache Blocking Strategies for High-Order Methods on CPUs.
    CEED5AM, 3–4 August 2021.
  2. W. Trojak, R. Watson, and F. D. Witherden,
    Hyperbolic Diffusion in Flux Reconstruction: Optimisation through Kernel Fusion within Tensor-Product Elements.
    CEED5AM, 3–4 August 2021.
  3. W. Trojak, T. Dzanic, and F. D. Witherden,
    Shock Capturing in Nodal Spectral Element Methods via Riemann Solutions for Intra-Element Fluxes.
    USNCCM 16, 25–29 July 2021.
  4. W. Trojak and F. D. Witherden,
    Fourier Analysis of Polynomial Multigrid for Arbitrary Multi-Stage Cycles.
    SIAM CSE21, 1–5 March 2021.
  5. S. Akkurt, F. D. Witherden, and P. E. Vincent,
    Cache Blocking Strategies for Kernel Fusion in High-Order Methods.
    SIAM CSE21, 1–5 March 2021.
  6. W. Trojak, T. Dzanic, and F. D. Witherden,
    Shock Capturing Methods in High-Order Flux Reconstruction I: Graph Viscosity and Convex Limiting Approaches.
    AIAA SciTech 2021, 11–15 and 19–21 January 2021.
  7. F. D. Witherden and W. Trojak,
    A Novel Vector Compression Scheme for High-Order Flow Solvers.
    WCCM–ECCOMAS 2020, 11–15 January 2021.
  8. T. Dzanic and F. D. Witherden,
    Variable Resolution Turbulence Modeling Within a Flux Reconstruction Framework.
    WCCM–ECCOMAS 2020, 11–15 January 2021.
  9. S. Akkurt, F. D. Witherden, and P. E. Vincent,
    Anisotropic Element-Local Implicit Time Stepping for High Order Flux Reconstruction.
    WCCM–ECCOMAS 2020, 11–15 January 2021.

2020

  1. S. Taghizadeh, Y. Hassan, F. D. Witherden, and S. S. Girimaji,
    Turbulence closure modeling with machine-learning methods: Influence of choice of neural network and training procedure.
    73rd Annual Meeting of the APS Division of Fluid Dynamics, 22–24 November 2020.
  2. T. Dzanic, W. Trojak, and F. D. Witherden,
    A Riemann Difference Scheme for Shock Capturing in Discontinuous Finite Element Methods.
    3rd Annual Meeting of the SIAM Texas–Louisiana section, 16–18 October 2020.
  3. F. D. Witherden and W. Trojak,
    Inline Vector Compression for Computational Physics.
    CEED4AM, 11–12 August 2020.
  4. F. D. Witherden,
    Impact of Number Representation for High-Order Implicit Large-Eddy Simulations.
    First PyFR Symposium, 19 June 2020.
  5. T. Dzanic and F. D. Witherden,
    Partially-Averaged Navier-Stokes in PyFR.
    First PyFR Symposium, 19 June 2020.
  6. F. D. Witherden,
    A Technical Overview of PyFR.
    First PyFR Symposium, 19 June 2020.
  7. W. Trojak and F. D. Witherden,
    Shock Capturing Methods for Flux Reconstruction.
    First PyFR Symposium, 19 June 2020.
  8. F. D. Witherden and P. E. Vincent,
    Experiences with OpenCL in PyFR: 2014—Present.
    IWOCL / SYCLcon 2020, 27–29 April 2020.
  9. F. D. Witherden,
    Anatomy of a High-performance FR CFD Solver.
    AIAA SciTech 2020, 6–10 January 2020, Orlando, Florida, USA.

2019

  1. S. Taghizadeh , F. D. Witherden, and S. S. Girimaji,
    Dynamical System Analysis of Data-Driven Turbulence Models.
    72nd Annual Meeting of the APS Division of Fluid Dynamics, 23–26 November 2019, Seattle, Washington, USA.
  2. C. Kamble, F. D. Witherden, and S. S. Girimaji,
    Investigation of Large-Scale Coherent Structures in Flow past a Sphere for Scale-Resolving Simulations (SRS).
    72nd Annual Meeting of the APS Division of Fluid Dynamics, 23–26 November 2019, Seattle, Washington, USA.
  3. T. S. Fowler IV, F. D. Witherden, and S. S. Girimaji,
    Pulsating Flow Past a Square Cylinder at Low Reynolds Number: Analysis of Vortex Structures.
    72nd Annual Meeting of the APS Division of Fluid Dynamics, 23–26 November 2019, Seattle, Washington, USA.
  4. N. A. Loppi, F. D. Witherden, and P. E. Vincent,
    A High-Order Cross-Platform Incompressible Navier–Stokes Solver via Artificial Compressibility: Application to Submarine Hydrodynamics.
    ICFD2019, 6–8 November 2019, Sendai, Miyagi, JP.
  5. F. D. Witherden,
    Anatomy of a High-performance FR CFD Solver.
    ICFD2019, 6–8 November 2019, Sendai, Miyagi, JP.
  6. F. D. Witherden, J. Morton, L. Peng, K. T. Carlberg, M. J. Kochenderfer, and A. Jameson,
    Compression of High-order CFD Solutions using Machine Learning.
    SIAM CSE19, 25–1 March 2019, Spokane, Washington, USA.

2017

  1. F. D. Witherden and A. Jameson,
    On the Impact of Number Representation for High-Order LES.
    USNCCM 14, 17–20 July 2017, Montréal, Quebec, CA.
  2. F. D. Witherden and A. Jameson,
    Predictive CFD, Past, Present, and Future.
    PCCFD 2017, 22–24 May 2017, KAUST, SA.
  3. Towards Greener Aviation with Python at Petascale.
    PCCFD 2017, 22–24 May 2017, KAUST, SA.
  4. F. D. Witherden, J. S. Park, A. Heinecke, P. H. J. Kelly, P. E. Vincent, and A. Jameson,
    PyFR and GiMMiK on Intel KNL: Performance, Scalability, and Applications.
    SIAM CSE17, 27–3 March 2017, Atlanta, Georgia, USA.

2016

  1. F. D. Witherden and P. E. Vincent,
    Petascale Computational Fluid Dynamics with Python on GPUs.
    NVIDIA GPU Technology Conference, 4–7 April 2016, San Jose, California, USA.

2015

  1. F. D. Witherden, M. Klemm, P. E. Vincent,
    PyFR: Heterogeneous Computing on Mixed Unstructured Grids with Python.
    EuroSciPy 2015, 26–29 August 2015, Cambridge, UK.
  2. P. E. Vincent, F. D. Witherden, A. M. Farrington, G. Ntemos, B. C. Vermeire, J. S. Park, and A. S. Iyer,
    PyFR: Next Generation Computational Fluid Dynamics on GPU Platforms.
    NVIDIA GPU Technology Conference, 17–20 March 2015, San Jose, California, USA.
  3. F. D. Witherden, B. D. Wozniak, F. P. Russel, P. E. Vincent, and P. H. J. Kelly,
    GiMMiK: Generating Bespoke Matrix-Multiplication Kernels for NVIDIA GPUs.
    NVIDIA GPU Technology Conference, 17–20 March 2015, San Jose, California, USA.
  4. F. D. Witherden and P. E. Vincent,
    Heterogeneous Computing with a Homogeneous Codebase.
    SIAM CSE15, 14–18 March 2015, Salt Lake City, Utah, USA.

2014

  1. F. D. Witherden, B. C. Vermeire, and P. E. Vincent,
    Heterogeneous Computing on Mixed Unstructured Grids with PyFR.
    UK Many-Core Developer Conference 2014, 15 December 2014, Cambridge, UK.
  2. F. D. Witherden,
    PyFR: Technical Challenges of Bringing Next Generation Computational Fluid Dynamics to GPU Platforms.
    NVIDIA GPU Technology Conference, 24–27 March 2014, San Jose, California, USA.

2013

  1. F. D. Witherden, A. M. Farrington, P. E. Vincent,
    PyFR: An Open Source Python Framework for High-Order CFD on Many-Core Platforms.
    4th International Congress on Computational Engineering and Sciences, 19–24 May 2013, Las Vegas, Nevada, USA.

Invited Presentations

2023

  1. F. D. Witherden,
    Elements of Modern Computing Hardware for Computational Fluid Dynamics.
    JAXA, 11 July 2023, Chofu-shi, Tokyo, JP.
  2. F. D. Witherden,
    FSSpMDM—Accelerating Small Sparse Matrix Multiplications by Run-Time Code Generation.
    FEM@LLNL Seminar Series, Lawrence Livermore National Laboratory, 20 June 2023, Livermore, California, USA.

2021

  1. F. D. Witherden,
    The PyFR Framework.
    Third School on numerical methods for parallel CFD, 16 December 2021.
  2. F. D. Witherden,
    PyFR: Facilitating Heterogeneous GPU Computing from a Homogeneous Codebase.
    University of Sheffield Lunch Bytes, 1 April 2021.
  3. F. D. Witherden,
    High-Order Accurate Computational Fluid Dynamics with Applications to a Spinning Golf Ball.
    Texas A&M University Ocean engineering seminar, 27 January 2021, College Station, Texas, USA.
  4. F. D. Witherden,
    PyFR: Current Capabilities and Future Roadmap.
    PyFR Seminar Series, 24 March 2021.
  5. F. D. Witherden,
    High-Order Accurate Computational Fluid Dynamics with Applications to a Spinning Golf Ball.
    Texas A&M University Ocean engineering seminar, 27 January 2021, College Station, Texas, USA.

2020

  1. F. D. Witherden,
    On the Identification of Symmetric Quadrature Rules for Finite Element Methods.
    Texas A&M University Aerospace engineering seminar, 17 September 2020, College Station, Texas, USA.

2019

  1. F. D. Witherden,
    High-Order Accurate Computational Fluid Dynamics with Applications to a Spinning Golf Ball.
    Department of Mechanical Engineering, Tohoku University, 5 November 2019, Sendai, Miyagi, JP.
  2. F. D. Witherden,
    High-Order Accurate Computational Fluid Dynamics with Applications to a Spinning Golf Ball.
    Institute of Fluid Science, Tohoku University, 5 November 2019, Sendai, Miyagi, JP.
  3. F. D. Witherden,
    On the Identification of Symmetric Quadrature Rules for Finite Element Methods.
    Lawrence Livermore National Laboratory, 9 October 2019, Livermore, California, USA.
  4. F. D. Witherden,
    On the Identification of Symmetric Quadrature Rules for Finite Element Methods.
    Texas A&M University Ocean engineering seminar, 25 April 2019, College Station, Texas, USA.

2018

  1. F. D. Witherden,
    Next Generation CFD: LES with High-Order Methods and Machine Learning.
    Cambridge University, 24 May 2018, Cambridge, UK.
  2. F. D. Witherden,
    Towards Greener Aviation with Python at Petascale.
    George Washington University, 22 February 2018, Washington, D.C., USA.

2017

  1. F. D. Witherden,
    On the Identification of Symmetric Quadrature Rules for Finite Element Methods.
    UC Berkeley scientific computing seminar, 1 November 2017, Berkeley, California, USA.
  2. F. D. Witherden,
    PyFR: High-Order Accurate Cross-Platform Petascale Computational Fluid Dynamics with Python.
    Princeton MAE seminar, 28 April 2017, Princeton, New Jersey, USA.
  3. F. D. Witherden,
    On the Identification of Symmetric Quadrature Rules for Finite Element Methods.
    Stanford ICME LA/Opt seminar, 13 April 2017, Stanford, California, USA.
  4. F. D. Witherden,
    PyFR: High-Order Accurate Cross-Platform Petascale Computational Fluid Dynamics with Python.
    Stanford CTR Turbulence Tea seminar, 10 March 2017, Stanford, California, USA.
  5. F. D. Witherden,
    PyFR: High-Order Accurate Cross-Platform Petascale Computational Fluid Dynamics with Python.
    Stanford ICME LA/Opt seminar, 9 February 2017, Stanford, California, USA.

2016

  1. F. D. Witherden and P. E. Vincent,
    PyFR: High-Order Accurate Cross-Platform Petascale Computational Fluid Dynamics with Python.
    AMS seminar series, NASA Ames Research Center, 31 May 2016, Moffett Field, California, USA.

2015

  1. F. D. Witherden,
    Next Generation High-Order CFD with PyFR.
    NASA Glenn Research Center, 18 February 2015, Cleveland, Ohio, USA.

Poster Presentations

2020

  1. T. Dzanic, K. Shah, and F. D. Witherden,
    Fourier Spectrum Discrepancies in Deep Network Generated Images.
    NeurIPS 2020, 6–12 December 2020.

2019

  1. N. A. Loppi, F. D. Witherden, and P. E. Vincent,
    A High-order Cross-platform Incompressible Navier-Stokes Solver via Artificial Compressibility with Application to Submarine Hydrodynamics.
    SIAM CSE19, 25–1 March 2019, Spokane, Washington, USA.

2018

  1. J. Morton, F. D. Witherden, A. Jameson, and M. J. Kochenderfer,
    Deep Dynamical Modeling and Control of Unsteady Fluid Flows.
    NeurIPS 2018, 2–8 December 2018, Montréal, Quebec, CA.
  2. P. E. Vincent, A. Iyer, F. D. Witherden, B. C. Vermeire, Y. Abe, R-D. Baier, and A. Jameson,
    High-Order Accurate Scale-Resolving Simulations of Low-Pressure Turbine Linear Cascades using Python at Petascale.
    2018 OLCF user meeting, 15–17 May 2018, Oak Ridge, Tennessee, USA.

2017

  1. J. Crabill, D. Manosalvas–Kjono, J. Romero, J. Watkins, F. D. Witherden, and A. Jameson,
    Recent Work in the Aerospace Computing Lab.
    PCCFD 2017, 22–24 May 2017, KAUST, SA.
  2. J. Crabill, D. Manosalvas–Kjono, J. Romero, J. Watkins, F. D. Witherden, and A. Jameson,
    Recent Work in the Aerospace Computing Lab.
    Stanford AA affiliates day, 19 April 2017, Stanford, California, USA.

2015

  1. F. D. Witherden, B. D. Wozniak, F. P. Russell, P. E. Vincent, and P. H. J. Kelly,
    Beating cuBLAS: Automatically Generating Bespoke Matrix Multiplication Kernels Using GiMMiK.
    SC15, 15–20 November 2015, Austin, Texas, USA.

2014

  1. F. D. Witherden, B. C. Vermeire, and P. E. Vincent,
    PyFR: An Open Source Python Framework for High-Order CFD on Heterogeneous Platforms.
    SC14, 16–21 November 2014, New Orleans, Louisiana, USA.

2013

  1. F. D. Witherden, A. M. Farrington, and P. E. Vincent,
    PyFR: An Open Source Python Framework for Solving Advection-Diffusion Type Problems on Streaming Architectures.
    UK Manycore Developer Conference 2013, 16–17 December 2013, Oxford, UK.
  2. F. D. Witherden, A. M. Farrington, and P. E. Vincent,
    PyFR: An Open Source Python Framework for High-Order CFD on Many-Core Platforms.
    4th International Congress on Computational Engineering and Sciences, 19–24 May 2013, Las Vegas, Nevada, USA.