Neural networks for large eddy simulations of wall-bounded turbulence: numerical experiments and challenges

Journal Article · Mon Jul 17 00:00:00 EDT 2023 · European Physical Journal. E, Soft Matter (print)

DOI:https://doi.org/10.1140/epje/s10189-023-00314-6· OSTI ID:2311707

Benjamin, Mark ^[1]; Domino, Stefan P. ^[2]; Iaccarino, Gianluca ^[1]

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1. Stanford Univ., CA (United States)
2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Here, we examine the application of neural network-based methods to improve the accuracy of large eddy simulations of incompressible turbulent flows. The networks are trained to learn a mapping between flow features and the subgrid scales, and applied locally and instantaneously—in the same way as traditional physics-based subgrid closures. Models that use only the local resolved strain rate are poorly correlated with the actual subgrid forces obtained from filtering direct numerical simulation data. We see that highly accurate models in a priori testing are inaccurate in forward calculations, owing to the preponderance of numerical errors in implicitly filtered large eddy simulations. A network that accounts for the discretization errors is trained and found to be unstable in a posteriori testing. We identify a number of challenges that the approach faces, including a distribution shift that affects networks that fail to account for numerical errors.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: NA0003525
• OSTI ID: 2311707
• Report Number(s): SAND--2023-06571J
• Journal Information: European Physical Journal. E, Soft Matter (print), Journal Name: European Physical Journal. E, Soft Matter (print) Journal Issue: 7 Vol. 46; ISSN 1292-8941
• Publisher: EDP Sciences
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS