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Title: Turbulence statistics in a spectral element code: a toolbox for High-Fidelity Simulations

Abstract

In the present document we describe a toolbox for the spectral-element code Nek5000, aimed at computing turbulence statistics. The toolbox is presented for a small test case, namely a square duct with L x = 2h, L y = 2h and L z = 4h, where x, y and z are the horizontal, vertical and streamwise directions, respectively. The number of elements in the xy-plane is 16 X 16 = 256, and the number of elements in z is 4, leading to a total of 1,204 spectral elements. A polynomial order of N = 5 is chosen, and the mesh is generated using the Nek5000 tool genbox. The toolbox presented here allows to compute mean-velocity components, the Reynolds-stress tensor as well as turbulent kinetic energy (TKE) and Reynolds-stress budgets. Note that the present toolbox allows to compute turbulence statistics in turbulent flows with one homogeneous direction (where the statistics are based on time-averaging as well as averaging in the homogeneous direction), as well as in fully three-dimensional flows (with no periodic directions, where only time-averaging is considered).

Authors:
 [1];  [2];  [1];  [2];  [2];  [1]
  1. KTH Mechanics, Stockholm (Sweden); Swedish e-Science Research Center (SeRC), Stockholm (Sweden)
  2. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1349052
Report Number(s):
ANL/MCS-TM-367
133610
DOE Contract Number:
AC02-06CH11357
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICS AND COMPUTING

Citation Formats

Vinuesa, Ricardo, Fick, Lambert, Negi, Prabal, Marin, Oana, Merzari, Elia, and Schlatter, Phillip. Turbulence statistics in a spectral element code: a toolbox for High-Fidelity Simulations. United States: N. p., 2017. Web. doi:10.2172/1349052.
Vinuesa, Ricardo, Fick, Lambert, Negi, Prabal, Marin, Oana, Merzari, Elia, & Schlatter, Phillip. Turbulence statistics in a spectral element code: a toolbox for High-Fidelity Simulations. United States. doi:10.2172/1349052.
Vinuesa, Ricardo, Fick, Lambert, Negi, Prabal, Marin, Oana, Merzari, Elia, and Schlatter, Phillip. Wed . "Turbulence statistics in a spectral element code: a toolbox for High-Fidelity Simulations". United States. doi:10.2172/1349052. https://www.osti.gov/servlets/purl/1349052.
@article{osti_1349052,
title = {Turbulence statistics in a spectral element code: a toolbox for High-Fidelity Simulations},
author = {Vinuesa, Ricardo and Fick, Lambert and Negi, Prabal and Marin, Oana and Merzari, Elia and Schlatter, Phillip},
abstractNote = {In the present document we describe a toolbox for the spectral-element code Nek5000, aimed at computing turbulence statistics. The toolbox is presented for a small test case, namely a square duct with Lx = 2h, Ly = 2h and Lz = 4h, where x, y and z are the horizontal, vertical and streamwise directions, respectively. The number of elements in the xy-plane is 16 X 16 = 256, and the number of elements in z is 4, leading to a total of 1,204 spectral elements. A polynomial order of N = 5 is chosen, and the mesh is generated using the Nek5000 tool genbox. The toolbox presented here allows to compute mean-velocity components, the Reynolds-stress tensor as well as turbulent kinetic energy (TKE) and Reynolds-stress budgets. Note that the present toolbox allows to compute turbulence statistics in turbulent flows with one homogeneous direction (where the statistics are based on time-averaging as well as averaging in the homogeneous direction), as well as in fully three-dimensional flows (with no periodic directions, where only time-averaging is considered).},
doi = {10.2172/1349052},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}

Technical Report:

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