Scientific multi-agent reinforcement learning for wall-models of turbulent flows

HJ Bae, P Koumoutsakos - Nature Communications, 2022 - nature.com
The predictive capabilities of turbulent flow simulations, critical for aerodynamic design and
weather prediction, hinge on the choice of turbulence models. The abundance of data from …

Non-Boussinesq subgrid-scale model with dynamic tensorial coefficients

R Agrawal, MP Whitmore, KP Griffin, ST Bose, P Moin - Physical Review Fluids, 2022 - APS
A major drawback of Boussinesq-type subgrid-scale stress models used in large-eddy
simulations is the inherent assumption of alignment between large-scale strain rates and …

Wall-modeled LES of shock-wave/boundary layer interaction

F De Vanna, M Bernardini, F Picano, E Benini - International Journal of …, 2022 - Elsevier
The present paper discusses the physical reliability of turbulence modeling in an adverse
pressure gradient wall flow setup at moderate/high Reynolds number by comparing wall …

[HTML][HTML] On the coupling between wall-modeled LES and immersed boundary method towards applicative compressible flow simulations

F De Vanna, G Baldan, F Picano, E Benini - Computers & Fluids, 2023 - Elsevier
The current work presents an innovative numerical technique for high-Reynolds/high-Mach
number compressible flow simulations in complex configurations. In particular, the research …

Grid resolution requirement for resolving rare and high intensity wall-shear stress events in direct numerical simulations

XIA Yang, J Hong, M Lee, XLD Huang - Physical Review Fluids, 2021 - APS
Turbulent signals are intermittent with large instantaneous fluctuations. Such large
fluctuations lead to small Kolmogorov scales that are hard to resolve in numerical …

Physics-informed machine-learning solution to log-layer mismatch in wall-modeled large-eddy simulation

S Maejima, K Tanino, S Kawai - Physical Review Fluids, 2024 - APS
This study proposes a physics-informed machine learning to enable using the erroneous
flow data at near-wall grid points as the input to the wall model in a wall-modeled large-eddy …

Multi-agent reinforcement learning for wall modeling in LES of flow over periodic hills

D Zhou, MP Whitmore, KP Griffin, HJ Bae - arXiv preprint arXiv …, 2022 - arxiv.org
We develop a wall model for large-eddy simulation (LES) that takes into account various
pressure-gradient effects using multi-agent reinforcement learning (MARL). The model is …

A priori assessment of nonlocal data-driven wall modeling in large eddy simulation

G Tabe Jamaat, Y Hattori - Physics of Fluids, 2023 - pubs.aip.org
In the present study, a priori assessment is performed on the ability of the convolutional
neural network (CNN) for wall-modeling in large eddy simulation. The data used for the …

A physics-inspired alternative to spatial filtering for large-eddy simulations of turbulent flows

PL Johnson - Journal of Fluid Mechanics, 2022 - cambridge.org
Large-eddy simulations (LES) are widely used for computing high Reynolds number
turbulent flows. Spatial filtering theory for LES is not without its shortcomings, including how …

Stochastic forcing for sub-grid scale models in wall-modeled large-eddy simulation

S Blanchard, N Odier, L Gicquel, B Cuenot… - Physics of Fluids, 2021 - pubs.aip.org
In the framework of wall-modeled large-eddy simulation (WMLES), the problem of combining
sub-grid scale (SGS) models with the standard wall law is commonly acknowledged and …