activity
20242026
collaborators

5 papers

physics.flu-dyn2026

Deep Learning-based Algebraic Reynolds Stress Closures for RANS Simulations of Turbulent Flows

Daniel Dehtyriov, Jonathan F. MacArt, Justin Sirignano

Turbulence is ubiquitous in engineering and science, yet direct simulation is prohibitively expensive. The Reynolds-averaged Navier-Stokes (RANS) equations provide savings exceedin…

physics.flu-dyn2025

Physics-Based Machine Learning Closures and Wall Models for Hypersonic Transition-Continuum Boundary Layer Predictions

Ashish S. Nair, Narendra Singh, Marco Panesi +2

Modeling rarefied hypersonic flows remains a fundamental challenge due to the breakdown of classical continuum assumptions in the transition-continuum regime, where the Knudsen num…

physics.flu-dyn2025

oRANS: Online optimisation of RANS machine learning models with embedded DNS data generation

Daniel Dehtyriov, Jonathan F. MacArt, Justin Sirignano

Deep learning (DL) has demonstrated promise for accelerating and enhancing the accuracy of flow physics simulations, but progress is constrained by the scarcity of high-fidelity tr…

physics.flu-dyn2025

OGF: An Online Gradient Flow Method for Optimizing the Statistical Steady-State Time Averages of Unsteady Turbulent Flows

Tom Hickling, Jonathan F. MacArt, Justin Sirignano +1

Turbulent flows are chaotic and unsteady, but their statistical distribution converges to a statistical steady state. Engineering quantities of interest typically take the form of…

physics.flu-dyn2024

Online Optimisation of Machine Learning Collision Models to Accelerate Direct Molecular Simulation of Rarefied Gas Flows

Nicholas Daultry Ball, Jonathan F. MacArt, Justin Sirignano

We develop an online optimisation algorithm for in situ calibration of collision models in simulations of rarefied gas flows. The online optimised collision models are able to achi…