English
Related papers

Related papers: Combination of Multi-Fidelity Data Sources For Unc…

200 papers

Uncertainty quantification is crucial for building reliable and trustable machine learning systems. We propose to estimate uncertainty in recurrent neural networks (RNNs) via stochastic discrete state transitions over recurrent timesteps.…

Machine Learning · Computer Science 2020-11-25 Cheng Wang , Carolin Lawrence , Mathias Niepert

Reynolds-Averaged Navier-Stokes(RANS) method will still play a vital role in the following several decade in aerospace engineering. Although RANS models are widely used, empiricism and large discrepancies between models reduce the…

Fluid Dynamics · Physics 2018-07-05 Weiwei Zhang , Linyang Zhu , Yilang Liu , Jiaqing Kou

Most turbulence models used in Reynolds-averaged Navier-Stokes (RANS) simulations are partial differential equations (PDE) that describe the transport of turbulent quantities. Such quantities include turbulent kinetic energy for eddy…

Fluid Dynamics · Physics 2022-02-18 Ruiying Xu , Xu-Hui Zhou , Jiequn Han , Richard P. Dwight , Heng Xiao

Traditional Reynolds-averaged Navier-Stokes (RANS) closures, based on the Boussinesq eddy viscosity hypothesis and calibrated on canonical flows, often yield inaccurate predictions of both mean flow and turbulence statistics. Here, we…

Direct numerical simulation (DNS) is very accurate however, the computational cost increases significantly with the increase in Reynolds number. On the other hand, we have the Reynolds Averaged Navier Stokes (RANS) method for simulating…

Fluid Dynamics · Physics 2023-01-12 Manthan Mahajan , Nitin Kumar , Deep Shikha , Vamsi K Chalamalla , Sawan S Sinha

For the purpose of Uncertainty Quantification (UQ) of Reynolds-Averaged Navier-Stokes closures, we introduce a framework in which perturbations in the eigenvalues of the anisotropy tensor are made in order to bound a Quantity-of-Interest…

Fluid Dynamics · Physics 2017-05-16 W. N. Edeling , G. Iaccarino , P. Cinnella

Despite their well-known limitations, RANS models remain the most commonly employed tool for modeling turbulent flows in engineering practice. RANS models are predicated on the solution of the RANS equations, but these equations involve an…

Fluid Dynamics · Physics 2020-04-22 Eric L. Peters , Riccardo Balin , Kenneth E. Jansen , Alireza Doostan , John A. Evans

Simulations based on Reynolds-Averaged Navier--Stokes (RANS) models have been used to support high-consequence decisions related to turbulent flows. Apart from the deterministic model predictions, the decision makers are often equally…

Fluid Dynamics · Physics 2017-01-25 Jian-Xun Wang , Jin-Long Wu , Heng Xiao

Despite the increasing availability of high-performance computational resources, Reynolds-Averaged Navier-Stokes (RANS) simulations remain the workhorse for the analysis of turbulent flows in real-world applications. Linear eddy viscosity…

Fluid Dynamics · Physics 2023-11-27 Leon Riccius , Atul Agrawal , Phaedon-Stelios Koutsourelakis

The objective of this work is to assess the impact of parameter uncertainty on hypersonic aerothermal surface heating predictions in Reynolds-Averaged Navier-Stokes (RANS) simulations using non-intrusive uncertainty quantification (UQ)…

Fluid Dynamics · Physics 2024-05-28 Jeremy Redding , Nick Plewacki , Himakar Ganti , Luis Bravo , Prashant Khare

This paper proposes a phenomenological Reynolds Averaged Navier-Stokes (RANS) calculation model based on physical constraints. In this model part of the source terms in the e equation was replaced with the deep learning model, using the…

Fluid Dynamics · Physics 2021-12-28 Shuming Zhang , Haiwang Li , Ruquan You , Tinglin Kong , Zhi Tao

To fully evaluate a turbulent flow, Direct Numerical Simulation (DNS) is the most accurate method by far and requires considerable computational power and time; not optimum for industry standards. Developing an alternative model, providing…

Fluid Dynamics · Physics 2022-07-04 Indrajit Nandi , Saikat Saha , Sabir Subedi , Sumon Saha

Turbulent flows play an important role in many scientific and technological design problems. Both Sub-Grid Scale (SGS) models in Large Eddy Simulations (LES) and Reynolds Averaged Navier Stokes (RANS) based modeling will require turbulence…

Fluid Dynamics · Physics 2024-07-16 Minghan Chu

In this paper, a novel zonal machine learning (ML) approach for Reynolds-averaged Navier-Stokes (RANS) turbulence modelling based on the divide-and-conquer technique is introduced. This approach involves partitioning the flow domain into…

Fluid Dynamics · Physics 2024-08-27 Anthony Man , Mohammad Jadidi , Amir Keshmiri , Hujun Yin , Yasser Mahmoudi

A probabilistic machine learning model is introduced to augment the $k-\omega\ SST$ turbulence model in order to improve the modelling of separated flows and the generalisability of learnt corrections. Increasingly, machine learning methods…

Computational Engineering, Finance, and Science · Computer Science 2023-01-24 Joel Ho , Nick Pepper , Tim Dodwell

Modeled Reynolds stress is a major source of model-form uncertainties in Reynolds-averaged Navier-Stokes (RANS) simulations. Recently, a physics-informed machine-learning (PIML) approach has been proposed for reconstructing the…

Fluid Dynamics · Physics 2021-07-23 Jian-Xun Wang , Junji Huang , Lian Duan , Heng Xiao

The present study represents a data-driven turbulent model with Galilean invariance preservation based on machine learning algorithm. The fully connected neural network (FCNN) and tensor basis neural network (TBNN) [Ling et al. (2016)] are…

Fluid Dynamics · Physics 2025-02-11 Xuepeng Fu , Shixiao Fu , Chang Liu , Mengmeng Zhang , Qihan Hu

Reynolds-Averaged Navier-Stokes (RANS) models are widely used for turbulent flow simulations due to their computational efficiency, but their accuracy strongly depends on the selected turbulence closure and may vary across the flow domain.…

Numerical Analysis · Mathematics 2026-03-18 Piero Zappi , Anna Ivagnes , Niccolò Tonicello , Gianluigi Rozza

A machine-learned (ML) model is developed to enhance the accuracy of turbulence transport equations of Reynolds Averaged Navier Stokes (RANS) solver and applied for periodic hill test case, which involves complex flow regimes, such as…

Fluid Dynamics · Physics 2023-05-24 Shanti Bhushan , Greg W. Burgreen , Wesley Brewer , Ian D. Dettwiller

We propose a data-driven, closure model for Reynolds-averaged Navier-Stokes (RANS) simulations that incorporates aleatoric, model uncertainty. The proposed closure consists of two parts. A parametric one, which utilizes previously proposed,…

Fluid Dynamics · Physics 2024-04-16 Atul Agrawal , Phaedon-Stelios Koutsourelakis