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Related papers: Normalizing Flows as a Novel PDF Turbulence Model

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Normalizing Flows (NFs) are flexible explicit generative models that have been shown to accurately model complex real-world data distributions. However, their invertibility constraint imposes limitations on data distributions that reside on…

Computer Vision and Pattern Recognition · Computer Science 2022-08-19 Janis Postels , Martin Danelljan , Luc Van Gool , Federico Tombari

A model for the pseudo-turbulent Reynolds stress tensor in compressible flows through monodisperse particle clouds is developed based on data from particle resolved numerical simulations. This model extends previous models for the…

Fluid Dynamics · Physics 2025-05-09 Andreas Nygård Osnes , Magnus Vartdal

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

A model of fully developed turbulence of a compressible fluid is briefly reviewed. It is assumed that fluid dynamics is governed by a stochastic version of Navier-Stokes equation. We show how corresponding field theoretic-model can be…

Statistical Mechanics · Physics 2018-10-09 M. Hnatič , N. M. Gulitskiy , T. Lučivjanský , L. Mižišin , V. Škultéty

We investigate relationships between statistics obtained from filtering and from ensemble or Reynolds-averaging turbulence flow fields as a function of length scale. Generalized central moments in the filtering approach are expressed as…

Fluid Dynamics · Physics 2021-03-17 J. A. Saenz , D. Aslangil , D. Livescu

This paper introduces a novel mathematical framework for examining the regularity and energy dissipation properties of solutions to the stochastic Navier-Stokes equations. By integrating Sobolev-Besov hybrid spaces, fractional differential…

Analysis of PDEs · Mathematics 2024-11-18 Rômulo Damasclin Chaves dos Santos , Jorge Henrique de Oliveira Sales

The Reynolds Averaged Navier Stokes (RANS) models are the most common form of model in turbulence simulations. They are used to calculate Reynolds stress tensor and give robust results for engineering flows. But RANS model predictions have…

Machine Learning · Computer Science 2022-03-17 Khashayar Nobarani , Seyed Esmaeil Razavi

The present study investigates the accurate inference of Reynolds-averaged Navier-Stokes solutions for the compressible flow over aerofoils in two dimensions with a deep neural network. Our approach yields networks that learn to generate…

Fluid Dynamics · Physics 2022-11-17 Li-Wei Chen , Nils Thuerey

The integration of interpretability and generalisability in data-driven turbulence modelling remains a fundamental challenge for computational fluid dynamics applications. This study yields a generalisable advancement of the $k$-$\omega$…

Fluid Dynamics · Physics 2025-07-02 Mario J. Rincón , Martino Reclari , Xiang I. A. Yang , Mahdi Abkar

Almost all investigations of turbulent flows in academia and in the industry utilize some degree of turbulence modeling. Of the available approaches to turbulence modeling Reynolds Stress Models have the highest potential to replicate…

Fluid Dynamics · Physics 2018-03-07 J. P. Panda , H. V. Warrior

In order to achieve a virtual certification process and robust designs for turbomachinery, the uncertainty bounds for Computational Fluid Dynamics have to be known. The formulation of turbulence closure models implies a major source of the…

Computational Engineering, Finance, and Science · Computer Science 2023-04-03 Marcel Matha , Karsten Kucharczyk , Christian Morsbach

We investigate the nonlinear dynamics of turbulent shear flows, with and without rotation, in the context of a simple but physically motivated closure of the equation governing the evolution of the Reynolds stress tensor. We show that the…

Astrophysics · Physics 2009-11-10 Pascale Garaud , Gordon I. Ogilvie

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

One route to improved predictive modeling of magnetically confined fusion reactors is to couple transport solvers with direct numerical simulations (DNS) of turbulence, rather than with surrogate models. An additional challenge presented by…

Plasma Physics · Physics 2018-07-16 Jeffrey B. Parker , Lynda L. LoDestro , Alejandro Campos

By means of the multifractal analysis (MFA), the expressions of the probability density functions (PDFs) are unified in a compact analytical formula which is valid for various quantities in turbulence. It is shown that the formula can…

Statistical Mechanics · Physics 2009-11-10 Toshihico Arimitsu , Naoko Arimitsu

Numerical models based on Reynolds-Averaged Navier-Stokes (RANS) equations are widely used in engineering turbulence modeling. However, the RANS predictions have large model-form uncertainties for many complex flows. Quantification of these…

Computational Physics · Physics 2017-01-25 Jian-Xun Wang , Rui Sun , Heng Xiao

Accurate and robust models for the pressure strain correlation are an essential component for the success of Reynolds Stress Models in turbulent flow simulations. However replicating the non-local action of pressure using only local tensors…

Fluid Dynamics · Physics 2019-03-14 Jyoti Prakash Panda

An analytical formula for the probability density function (PDF) of the velocity fluctuation in fully-developed turbulence is derived, non-perturbatively, by assuming that its underlying statistics is the one based on the generalized…

Statistical Mechanics · Physics 2015-06-24 Toshihico Arimitsu , Naoko Arimitsu

Extending gradient-type turbulence closures to turbulent premixed flames is challenging due to the significant influence of combustion heat release. We incorporate a deep neural network (DNN) into Reynolds-averaged Navier--Stokes (RANS)…

Fluid Dynamics · Physics 2025-06-18 Priyesh Kakka , Jonathan F. MacArt

In probability density function (PDF) methods of turbulent flows, the joint PDF of several flow variables is computed by numerically integrating a system of stochastic differential equations for Lagrangian particles. A set of parallel…

Fluid Dynamics · Physics 2010-06-04 J. Bakosi , P. Franzese , Z. Boybeyi