The Center of Excellence in Combustion has facilitated the development of software and methodologies to drive the design of the next generation of hydrogen turbines for power generation and aircraft propulsion
Utilizing cutting-edge supercomputing technologies, scientists from the European Union and the United Kingdom are making remarkable advances in facilitating the deployment of sustainable fuels for the future. Their collaborative efforts, spearheaded by the Center of Excellence in Combustion (CoEC), project coordinated by the Barcelona Supercomputing Center - Centro Nacional de Supercomputación (BSC-CNS), focus on using advanced modelling and simulation technologies to study the combustion of sustainable fuels and new combustion technologies. They aim to transform Europe´s power and transportation sectors, fostering the creation of the next generation of eco-friendly fuels.
Addressing challenges in computational combustion, the CoEC project has achieved groundbreaking results in the past three years. Formed by a consortium of 11 institutions, including supercomputing centers, laboratories, and universities, CoEC was created to apply exascale computing technologies to promote and develop advanced simulation software that support the decarbonisation goals of the European Union within the energy and transportation sectors.
The reasons for that collective effort have been substantial. The transportation industry is responsible for 20% of the world's CO2 emissions, making it the second-largest contributor to global carbon pollution, as stated by the International Energy Agency. That is why, at COP28 in November 2023 in the United Arab Emirates, nearly 200 countries agreed to a transition “away from fossil fuels in energy systems in a just, orderly, and equitable manner, accelerating action in this critical decade to achieve net zero by 2050 in keeping with the science”.
“CoEC was primarily driven by the need for energy transition, and it is aligned with European decarbonisation objectives, which deal with fundamental problems posed to our community, such as the need for new fuels and how these fuels perform in various systems. Additionally, CoEC explored any possible modifications needed for current engines to use them more efficiently”, said Daniel Mira, CoEC coordinator and senior researcher at the Barcelona Supercomputing Center (BSC). The project also addressed innovative applications, particularly focusing on redesigning combustion systems, with a primary emphasis on utilizing hydrogen across various sectors.
“I believe that combustion science can help produce novel propulsion and energy technologies”, explained Epaminondas Mastorakos, CoEC team leader and Hopkinson/ICI Professor of Applied Thermodynamics at the University of Cambridge. “And it is not only the new fuels – it is also battery fires, wildfires, material synthesis, and other problems that fall within our remit. We can play a major role in changing the world for the better”.
Hydrogen combustion
Scientists involved in the project have achieved remarkable results, with one notable breakthrough linked to hydrogen combustion.
Introducing new fuels, such as hydrogen or sustainable aviation fuel, can significantly reduce carbon-related emissions, reaching net zero in the case of hydrogen combustion. For instance, high-fidelity simulations were conducted to explore hydrogen combustion using a lab-scale gas turbine combustor model that had been experimentally characterized at TU Berlin. The numerical results from these simulations contributed to understanding the primary characteristics of the flame and major chemical pathways for NOx formation, shedding light onto its stabilisation mechanisms, and revealing insights into flame resistance. Throughout this journey, the CoEC project has also facilitated the development of various software and methodologies to assist industrial partners in designing the next generation of hydrogen turbines for power generation and aviation propulsion. These tools can also support the operation and optimisation of wind farms and enhance the efficiency of chemical reactors.
Net-zero carbon emissions
Another key breakthrough is associated with the aviation sector's transition to net-zero carbon emissions. In the quest for net-zero carbon emissions in the aviation sector, this breakthrough involves understanding soot formation in aero-engines, as the emission of these carbon nanoparticles poses risks to both human health and the environment. Collaborative efforts between BSC and TU/e, RWTH Aachen, TU Darmstadt, ETH Zurich and AUTH conducted numerical studies of soot formation in lab-scale combustors, combining simulations and experimental measurements to elucidate mechanisms governing soot emissions and performing Direct Numerical Simulations that can provide fundamental understanding of soot formation in practical applications. Numerical results guide the development of mitigation strategies, offering valuable insights for optimising the burner's operation and limiting the emission of soot particles.
Additionally, CoEC has pioneered High-Performance Computing codes to explore the combustion of iron powder and hydrogen. This cyclic, carbon-free fuel holds the potential for storing and transporting renewable energy, and a deep understanding of its combustion is crucial for developing burner technology. Simulations of combustion of iron particles in CoEC's codes has provided insights into iron powder flames, opening avenues for simulating iron powder combustion in industrial applications. The prediction of soot pollutant emissions, a complex challenge involving multi-phase processes and intricate physicochemical mechanisms, is addressed successfully in the study. This research has significant implications for developing low-emission aero-engines, particularly those fueled by Sustainable Aviation Fuels (SAF).
“To avoid the emission of carbon oxides, the most direct solution is to burn fuels that do not contain carbon, said Dr-HdR Bénédicte Cuenot, the leader of the combustion research group at CERFACS, France. CERFACS has developed advanced and massively parallel software for the numerical simulation (DNS and LES) of turbulent combustion and heat transfer (including thermal radiation) in industrial systems. According to Dr Cuenot, these fuels must be easy to find and burn; Hydrogen, Ammonia, and metal powders are among the good candidates. “But they require redesigning all industrial systems. This can be made via numerical simulation, which has become essential for innovation”, adds Bénédicte Cuenot.
Exascale-scale simulations
Another exciting project result is connected to the visualisation of the extreme amount of data from exascale-scale simulations of nekCRF. Exascale supercomputers are the most powerful high-performance computers available today. One such system, called JUPITER, will be built in Europe in 2024 and hosted at the Jülich Supercomputing Centre (JSC), Germany. All exascale supercomputers use GPUs for most of their performance, in contrast to petascale systems that use CPUs for most of their performance. Simply optimising code developed for CPU systems to run efficiently on GPUs is typically impossible. Therefore, new simulation codes must be developed, which is highly non-trivial for complex simulations such as combustion applications.
Several partners of CoEC, such as ETHZ, AUTH, and FZJ, have enabled the reactive flow solver nekCRF, designed to make the most efficient use of the latest GPUs. nekCRF allows complex combustion applications to be computed with unprecedented degrees of freedom that significantly accelerates the time to a solution. A particular focus has been placed on optimising nekCRF for the hardware of Europe's first exascale supercomputer, JUPITER, to enable one of the largest combustion simulations in the world and the largest ever in Europe. Using the nekRS framework, nekCRF also benefits from other CoEC developments, such as our novel pipeline for in-transit visualisation. This visualisation pipeline helps manage the extreme amount of data from exascale-scale simulations and was recently recognised with the Best Paper Award at ISAV23 during the Supercomputing Conference 2023.
“Simulation has become the third scientific pillar alongside theory and experiment. We are just at the beginning of developing hydrogen aero gas turbines”, said Christian Hasse, Professor in the Department of Mechanical Engineering at the Darmstadt University of Technology, Germany, and one of the team leaders of CoEC. “The combination of unique experiments and, particularly important for CoEC, high-performance computing, provides insights into combustion processes that were unthinkable ten years ago”, completes Hasse.
About CoEC
CoEC is a collective effort to exploit Exascale computing technologies to address fundamental challenges related to the simulation of combustion systems, which will create a positive impact on the EU´s decarbonisation goals. Coordinated by the Barcelona Supercomputing Center and granted with a budget of over €5.6M by the European Commission, the project ran from 1 October 2020 to 30 December 2023.
Other partners in the consortium include leading institutions in the fields of computational combustion and High-Performance Computing such as Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique (CERFACS), RWTH Aachen University, Eindhoven University of Technology, University of Cambridge, Centre National de la Recherche Scientifique (CNRS), Technical University of Darmstadt, ETH Zürich, Aristotle University of Thessaloniki, Forschungszentrum Jülich (FZJ) and National Center for Supercomputing Applications.
The CoEC project has received funding from the European Union’s Horizon 2020 research and innovation programme under the grant agreement Nº 952181.