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Related papers: Large Eddy Simulations in Astrophysics

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In this paper a procedure for large-eddy simulation (LES) has been devised for fluid and magnetohydrodynamic turbulence in Fourier space using the renormalized parameters. The parameters calculated using field theory have been taken from…

Chaotic Dynamics · Physics 2009-11-10 Mahendra K. Verma , Shishir Kumar

Large Eddy Simulation (LES) is a very useful tool when simulating turbulent flows if we are only interested in its "larger" scales. One of the possible ways to derive the LES equations is to apply a filter operator to the Navier-Stokes…

Analysis of PDEs · Mathematics 2017-03-14 José M. Rodríguez , Raquel Taboada-Vázquez

This paper studies the large-eddy simulation (LES) of isothermal turbulent channel flows. We investigate zero-equation algebraic models without wall function or wall model: functional models, structural models and mixed models. In addition…

Fluid Dynamics · Physics 2020-06-09 Dorian Dupuy , Adrien Toutant , Françoise Bataille

An analysis of the turbulence-radiation interaction in the framework of large eddy simulation (LES) is presented. Direct numerical simulation (DNS) of statistical steady forced homogeneous isotropic turbulence is used to evaluate the…

Fluid Dynamics · Physics 2019-03-14 Maxime Roger , Pedro Coelho , Carlos Da Silva

Large eddy simulations (LES) are a powerful tool in understanding processes that are inaccessible by direct simulations due to their complexity, for example, in the highly turbulent regime. However, their accuracy and success depends on a…

Fluid Dynamics · Physics 2017-03-27 Philipp Grete , Dimitar G Vlaykov , Wolfram Schmidt , Dominik R G Schleicher

Systems comprising a turbulent channel flow overlaying a permeable bed can be found in a variety of industrial and natural applications (e.g. urban planning, fracking, submerged vegetation). One important realization of this system is at…

Fluid Dynamics · Physics 2017-08-01 Benjamin H. Sonin

Large-eddy simulation developments and validations are presented for an improved simulation of turbulent internal flows. Numerical methods are proposed according to two competing criteria: numerical qualities (precision and spectral…

Fluid Dynamics · Physics 2008-01-15 Jérôme Boudet , Joëlle Caro , L. Shao , Emmanuel Lévêque

Large-eddy simulations (LES) are widely-used for computing high Reynolds number turbulent flows. Spatial filtering theory for LES is not without its shortcomings, including how to define filtering for wall-bounded flows, commutation errors…

Fluid Dynamics · Physics 2022-02-02 Perry L. Johnson

Large-eddy simulation (LES) of a turbulent flow through an array of building-like obstacles is an idealized model to study transport of contaminants in the urban atmospheric boundary layer (UABL). A reasonably accurate LES prediction of…

Fluid Dynamics · Physics 2017-11-09 Jahrul M Alam , Luke P. J. Fitzpatrick

Current design constraints have encouraged the studies of aeroacoustics fields around compressible jet flows. The present work addresses the numerical study of unsteady turbulent jet flows for aeroacoustic analyses of main engine rocket…

Fluid Dynamics · Physics 2022-12-26 Carlos Junqueira-Junior , Sami Yamouni , Joao Luiz F. Azevedo , William Wolf

With the continuing progress in large eddy simulations (LES), and ever increasing computational resources, it is currently possible to numerically solve the time-dependent and anisotropic large scales of turbulence in a large variety of…

Fluid Dynamics · Physics 2021-12-14 Ryan D. Hass , Aditya S. Ghate , Sanjiva K. Lele

Extensive experimental evidence highlight that scalar turbulence exhibits anomalous diffusion and stronger intermittency levels at small scales compared to that in fluid turbulence. This renders the corresponding subgrid-scale dynamics…

Fluid Dynamics · Physics 2024-06-19 S. Hadi Seyedi , Ali Akhavan-Safaei , Mohsen Zayernouri

We present a numerical method for Large Eddy Simulations (LES) of compressible two-phase flows. The method is validated for the flow in a micro channel with a step-like restriction. This setup is representative for typical cavitating…

Fluid Dynamics · Physics 2014-01-28 S Hickel , M. Mihatsch , S. J. Schmidt

One promising decomposition of turbulent dynamics is that into building blocks such as equilibrium and periodic solutions and orbits connecting these. While the numerical approximation of such building blocks is feasible for flows in small…

Fluid Dynamics · Physics 2018-11-14 Lennaert van Veen , Genta Kawahara , Tatsuya Yasuda

We study the numerical errors of large-eddy simulation (LES) in isotropic and wall-bounded turbulence. A direct-numerical-simulation (DNS)-aided LES formulation, where the subgrid-scale (SGS) term of the LES is computed by using filtered…

Fluid Dynamics · Physics 2022-08-05 H. Jane Bae , Adrian Lozano-Duran

We describe and compare two time-periodic flows embedded in Large Eddy Simulation (LES) of turbulence in a three-dimensional, periodic domain subject to constant external forcing. One of these flows models the regeneration of large-scale…

Fluid Dynamics · Physics 2019-02-20 Lennaert van Veen , Alberto Vela Martin , Genta Kawahara , Tatsuya Yasuda

A new method for the localization of the regions where small scale turbulent fluctuations are present in hypersonic flows is applied to the large-eddy simulation (LES) of a compressible turbulent jet with an initial Mach number equal to 5.…

Fluid Dynamics · Physics 2015-06-12 D. Tordella , M. Iovieno , S. Massaglia , A. Mignone

We present a Large Eddy Simulation (LES) approach based on a nonlinear differential low-pass filter for the simulation of two-dimensional barotropic flows with under-refined meshes. For the implementation of such model, we choose a…

Numerical Analysis · Mathematics 2022-02-02 Michele Girfoglio , Annalisa Quaini , Gianluigi Rozza

Turbulence in fluids, gases, and plasmas remains an open problem of both practical and fundamental importance. Its irreducible complexity usually cannot be tackled computationally in a brute-force style. Here, we combine Large Eddy…

Computational Physics · Physics 2023-09-29 Robin Greif , Frank Jenko , Nils Thuerey

In this paper we employ renormalized viscosity and thermal diffusivity to construct a subgrid-scale model for large eddy simulation (LES) of turbulent thermal convection. For LES, we add $\nu_\mathrm{ren} \propto \Pi_u^{1/3}…

Fluid Dynamics · Physics 2018-10-31 Sumit Vashishtha , Mahendra K. Verma