Turbulence from an observer perspective

TA Zaki - Annual Review of Fluid Mechanics, 2024 - annualreviews.org
Turbulence is often studied by tracking its spatiotemporal evolution and analyzing the
dynamics of its different scales. The dual to this perspective is that of an observer who starts …

DeepM&Mnet: Inferring the electroconvection multiphysics fields based on operator approximation by neural networks

S Cai, Z Wang, L Lu, TA Zaki, GE Karniadakis - Journal of Computational …, 2021 - Elsevier
Electroconvection is a multiphysics problem involving coupling of the flow field with the
electric field as well as the cation and anion concentration fields. Here, we use …

Neural operator prediction of linear instability waves in high-speed boundary layers

PC Di Leoni, L Lu, C Meneveau, GE Karniadakis… - Journal of …, 2023 - Elsevier
We investigate if neural operators can predict the linear evolution of instability waves in high-
speed boundary layers. To this end, we extend the design of the DeepOnet to ensure …

Reconstructing turbulent velocity and pressure fields from under-resolved noisy particle tracks using physics-informed neural networks

P Clark Di Leoni, K Agarwal, TA Zaki, C Meneveau… - Experiments in …, 2023 - Springer
Volume-resolving imaging techniques are rapidly advancing progress in experimental fluid
mechanics. However, reconstructing the full and structured Eulerian velocity and pressure …

Instability-wave prediction in hypersonic boundary layers with physics-informed neural operators

Y Hao, PC Di Leoni, O Marxen, C Meneveau… - Journal of …, 2023 - Elsevier
Fast and accurate prediction of the nonlinear evolution of instability waves in high-speed
boundary layers requires specialized numerical algorithms, and augmenting limited …

State estimation in minimal turbulent channel flow: A comparative study of 4DVar and PINN

Y Du, M Wang, TA Zaki - International Journal of Heat and Fluid Flow, 2023 - Elsevier
The state of turbulent, minimal-channel flow is estimated from spatio-temporal sparse
observations of the velocity, using both a physics-informed neural network (PINN) and …

Ensemble-variational assimilation of statistical data in large-eddy simulation

V Mons, Y Du, TA Zaki - Physical Review Fluids, 2021 - APS
A nonintrusive data assimilation methodology is developed to improve the statistical
predictions of large-eddy simulations (LES). The ensemble-variational (EnVar) approach …

Unsteady flow enhancement on an airfoil using sliding window weak-constraint four-dimensional variational data assimilation

S Li, C He, Y Liu - Physics of Fluids, 2023 - pubs.aip.org
This study establishes a continuous sliding window weak-constraint four-dimensional
variational approach for reproducing a complete instantaneous flow from sparse …

Multi-scale reconstruction of turbulent rotating flows with generative diffusion models

T Li, AS Lanotte, M Buzzicotti, F Bonaccorso, L Biferale - Atmosphere, 2023 - mdpi.com
We address the problem of data augmentation in a rotating turbulence set-up, a
paradigmatic challenge in geophysical applications. The goal is to reconstruct information in …

Linear-model-based estimation in wall turbulence: improved stochastic forcing and eddy viscosity terms

V Gupta, A Madhusudanan, M Wan… - Journal of Fluid …, 2021 - cambridge.org
We use Navier–Stokes-based linear models for wall-bounded turbulent flows to estimate
large-scale fluctuations at different wall-normal locations from their measurements at a …