Dr Thomas Howarth

MMath, PhD

  • Lecturer in Computational Thermofluids
Publications
Google Scholar
Thomas Howarth

Background:

Dr. Thomas Howarth holds an educational background in Applied Mathematics, earning his Master’s degree with a thesis on numerical solutions of partial differential equations on surfaces at the University of Warwick. He then pursued a PhD at Newcastle University under the supervision of Dr. Andy Aspden, where his research focused on the simulation and modelling of thermodiffusively-unstable premixed hydrogen flames and pressurised micromix combustors, in a project sponsored by Reaction Engines Ltd.

Following his PhD, Dr. Howarth joined RWTH Aachen as a Postdoctoral Researcher under Prof. Heinz Pitsch. There, he designed and executed simulations on some of Europe’s largest supercomputing systems, developing models for carbon-free combustion under highly turbulent and pressurised conditions. His work bridges advanced numerical methods, high-performance computing, and practical combustion applications.

Thomas joined the department as a Lecturer in Computational Thermofluids in 2025.

Qualifications:

  • MMath (1st class, hons.), University of Warwick, 2019
  • PhD, Newcastle University, ‘Direct numerical simulation and modelling of thermodiffusively-unstable lean premixed hydrogen flames and high-pressure micromix combustors’, 2023

Key awards:

  • Finalist, 2024 Osborne Reynolds Prize

 

Outline of main research interests: 

Fundamental fluid dynamics and combustion via the usage of high-performance computing systems. This involves both the development and usage of computational fluid dynamics (CFD) software in the following areas:

  • Direct numerical simulation (DNS):
    • Non-reacting flow and turbulent mixing
    • Reacting flow with detailed chemistry
  • Mathematical modelling
    • Scaling law development
    • Quasi-1D models
  • Large-eddy simulation (LES)

Rigorous and modern software development for CFD, including extensive use of AMReX-based software (e.g. PeleLMeX), with further interests in:

  • Adaptive mesh refinement (AMR)
  • GPU acceleration
  • Numerical methods for reacting and non-reacting flow

Publications:

  • T. L. Howarth, S. Nerzak, P. Gruhlke, J. T. Lipkowicz, L. Panek, S. Pfadler, M. Gauding, and H. Pitsch, “Structure and nitrogen oxide emissions of confined turbulent hydrogen jet flames”, Proceedings of the Combustion Institute 41 (2025): 105851.
  • T. Lehmann, L. Berger, T. L. Howarth, M. Gauding, S. Girhe, B. B. Dally & H. Pitsch, “Comprehensive linear stability analysis for intrinsic instabilities in premixed ammonia/hydrogen/air flames”, Combustion and Flame 273 (2025): 113927.
  • G. Russell, T. L. Howarth, A. W. Skiba, C. D. Carter, A. J. Aspden, “Turbulence-flame interactions in high-Karlovitz-number lean premixed hydrogen piloted jet flames”, Proceedings of the Combustion Institute 41 (2025): 105868

Selected Publications:

  • T. L. Howarth, A. J. Aspden, “An empirical characteristic scaling model for freely-propagating lean premixed hydrogen flames”, Combustion and Flame 237 (2022): 111805
  • T. L. Howarth, E. F. Hunt, A. J. Aspden, “Thermodiffusively-unstable lean premixed hydrogen flames: phenomenology, empirical modelling, and thermal leading points”, Combustion and Flame 253 (2023): 112811
  • T. L. Howarth, M. A. Picciani, E. S. Richardson, M. S. Day, A. J. Aspden, “Direct numerical simulation of a high-pressure hydrogen micromix combustor: Flame structure and stabilisation mechanism”, Combustion and Flame 265 (2024): 113504

External collaborators:

  • Newcastle University, UK
  • Reaction Engines Ltd., UK
  • NREL, USA
  • RWTH Aachen, Germany
  • TU Darmstadt, Germany
  • Siemens Energy, Germany