Adaptive scale resolving for turbulent jets using data assimilation augmented Reynolds-averaged simulations DOI
Zhiyang Li, Chuangxin He, Yingzheng Liu

et al.

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(10)

Published: Oct. 1, 2024

This study proposes a turbulence model called the PaSAS–Re which has low computational cost. The proposed can predict time-averaged flow accurately and fluctuation field for turbulent jets. A data assimilation that mean distribution in free jets wall is used as parent model. scale-adaptive simulation (SAS) source term added to equip it with ability achieve behavior like large-eddy simulation. However, SAS approach cannot switch scale-resolving mode if flow, such jet, does not exhibit sufficiently strong instability. Therefore, partially averaged Navier–Stokes (PANS) this generate necessary instabilities. PANS converts modeled kinetic energy k into resolved fluctuation, beneficial activating tested on impinging using coarse meshes highlight its results of velocity show best performance achieved fk = 0.8. effects approach, vortex stretching term, prediction are analyzed found be important predicting generating dynamic behavior. Finally, simulations conducted further verification application suitable fluctuations. engineering obtain

Language: Английский

Turbulence closure modeling with machine learning: a foundational physics perspective DOI Creative Commons
Sharath S. Girimaji

New Journal of Physics, Journal Year: 2024, Volume and Issue: 26(7), P. 071201 - 071201

Published: July 1, 2024

Abstract Turbulence closure modeling using machine learning (ML) is at an early crossroads. The extraordinary success of ML in a variety challenging fields had given rise to expectation similar transformative advances the area turbulence modeling. However, by most accounts, current rate progress toward accurate and predictive ML-RANS (Reynolds Averaged Navier–Stokes) models has been very slow. Upon retrospection, absence rapid can be attributed two factors: underestimation intricacies overestimation ML’s ability capture all features without employing targeted strategies. To pave way for more meaningful closures tailored address nuances turbulence, this article seeks review foundational flow physics assess challenges context data-driven approaches. Revisiting analogies with statistical mechanics stochastic systems, key physical complexities mathematical limitations are explicated. It noted that approaches do not systematically inherent approach or inadequacies forms expressions. study underscores drawbacks supervised learning-based stresses importance discerning framework. As methods evolve (which happening pace) our understanding phenomenon improves, inferences expressed here should suitably modified.

Language: Английский

Citations

8

Adaptive scale resolving for turbulent jets using data assimilation augmented Reynolds-averaged simulations DOI
Zhiyang Li, Chuangxin He, Yingzheng Liu

et al.

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(10)

Published: Oct. 1, 2024

This study proposes a turbulence model called the PaSAS–Re which has low computational cost. The proposed can predict time-averaged flow accurately and fluctuation field for turbulent jets. A data assimilation that mean distribution in free jets wall is used as parent model. scale-adaptive simulation (SAS) source term added to equip it with ability achieve behavior like large-eddy simulation. However, SAS approach cannot switch scale-resolving mode if flow, such jet, does not exhibit sufficiently strong instability. Therefore, partially averaged Navier–Stokes (PANS) this generate necessary instabilities. PANS converts modeled kinetic energy k into resolved fluctuation, beneficial activating tested on impinging using coarse meshes highlight its results of velocity show best performance achieved fk = 0.8. effects approach, vortex stretching term, prediction are analyzed found be important predicting generating dynamic behavior. Finally, simulations conducted further verification application suitable fluctuations. engineering obtain

Language: Английский

Citations

1