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Challenges and opportunities in exascale fusion simulations

Nature Reviews Physics volume 7, pages 355–364 (2025)Cite this article

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Abstract

The challenging computational requirements of nuclear fusion research arise from the multiple timescales and space scales involved in the physics and engineering processes of a fusion device. Owing to the intrinsic and complex interconnections of these processes, the complex multiphysics and multiscale nature of fusion simulations require the capabilities of cutting-edge supercomputers. Advances in supercomputing enable a move towards larger-scale, higher-fidelity full fusion reactor digital models that capture not only the plasma core and edge physics but also interactions with materials and engineering aspects, such as fusion reactor walls and cooling systems. This Perspective discusses the main opportunities that fusion codes face in the transition to the emerging exascale systems and beyond, and the challenges that remain to be overcome.

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Fig. 1: Fusion reactor modelling.
Fig. 2: Software tools to exploit parallelism, computing capabilities and data storage.

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Acknowledgements

This work has been carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (Grant Agreement No. 101052200 — EUROfusion). Views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them. In addition, the work has been partly co-financed by grant PID2023-148038OB-I00 funded by MICIU/AEI/10.13039/501100011033/ and by the Departament de Recerca i Universitats de la Generalitat de Catalunya with code 2021 SGR 00908. The authors thank F. Cipolletta, D. Gallart, J. J. Gutierrez Moreno, J. J. Labarta Mancho and A. Soba for discussions.

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  1. Barcelona Supercomputing Center, Barcelona, Spain

    Marta Garcia-Gasulla & Mervi J. Mantsinen

  2. ICREA, Barcelona, Spain

    Mervi J. Mantsinen

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Garcia-Gasulla, M., Mantsinen, M.J. Challenges and opportunities in exascale fusion simulations. Nat Rev Phys 7, 355–364 (2025). https://doi.org/10.1038/s42254-025-00830-8

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