Turbulence statistics in a spectral element code: a toolbox for HighFidelity Simulations
Abstract
In the present document we describe a toolbox for the spectralelement 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 xyplane 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 meanvelocity components, the Reynoldsstress tensor as well as turbulent kinetic energy (TKE) and Reynoldsstress budgets. Note that the present toolbox allows to compute turbulence statistics in turbulent flows with one homogeneous direction (where the statistics are based on timeaveraging as well as averaging in the homogeneous direction), as well as in fully threedimensional flows (with no periodic directions, where only timeaveraging is considered).
 Authors:
 KTH Mechanics, Stockholm (Sweden); Swedish eScience Research Center (SeRC), Stockholm (Sweden)
 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/MCSTM367
133610
 DOE Contract Number:
 AC0206CH11357
 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 HighFidelity 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 HighFidelity 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 HighFidelity 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 HighFidelity 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 spectralelement 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 xyplane 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 meanvelocity components, the Reynoldsstress tensor as well as turbulent kinetic energy (TKE) and Reynoldsstress budgets. Note that the present toolbox allows to compute turbulence statistics in turbulent flows with one homogeneous direction (where the statistics are based on timeaveraging as well as averaging in the homogeneous direction), as well as in fully threedimensional flows (with no periodic directions, where only timeaveraging 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}
}

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