Wallresolved spectral cascadetransport turbulence model
Abstract
A spectral cascadetransport model has been developed and applied to turbulent channel flows (Reτ= 550, 950, and 2000 based on friction velocity, uτ ; or ReδΜ= 8,500; 14,800 and 31,000, based on the mean velocity and channel halfwidth). This model is an extension of a spectral model previously developed for homogeneous single and twophase decay of isotropic turbulence and uniform shear flows; and a spectral turbulence model for wallbounded flows without resolving the boundary layer. Data from direct numerical simulation (DNS) of turbulent channel flow was used to help develop this model and to assess its performance in the 1D direction across the channel width. The resultant spectral model is capable of predicting the mean velocity, turbulent kinetic energy and energy spectrum distributions for singlephase wallbounded flows all the way to the wall, where the model source terms have been developed to account for the wall influence. We implemented the model into the 3D multiphase CFD code NPHASECMFD and the latest results are within reasonable error of the 1D predictions.
 Authors:
 North Carolina State Univ., Raleigh, NC (United States). Dept. of Nuclear Engineering
 Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Energy Division
 Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Mechanical Aerospace and Nuclear Engineering
 Publication Date:
 Research Org.:
 Argonne National Lab. (ANL), Argonne, IL (United States)
 Sponsoring Org.:
 USDOE Office of Nuclear Energy (NE)
 OSTI Identifier:
 1393902
 Grant/Contract Number:
 AC0206CH11357; AC0500OR22725
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Nuclear Engineering and Design
 Additional Journal Information:
 Journal Volume: 320; Journal Issue: C; Journal ID: ISSN 00295493
 Publisher:
 Elsevier
 Country of Publication:
 United States
 Language:
 English
 Subject:
 22 GENERAL STUDIES OF NUCLEAR REACTORS; CFD; DNS; channel flow; spectralcascade; turbulence model
Citation Formats
Brown, C. S., Shaver, D. R., Lahey, R. T., and Bolotnov, I. A. Wallresolved spectral cascadetransport turbulence model. United States: N. p., 2017.
Web. doi:10.1016/j.nucengdes.2017.06.001.
Brown, C. S., Shaver, D. R., Lahey, R. T., & Bolotnov, I. A. Wallresolved spectral cascadetransport turbulence model. United States. doi:10.1016/j.nucengdes.2017.06.001.
Brown, C. S., Shaver, D. R., Lahey, R. T., and Bolotnov, I. A. Sat .
"Wallresolved spectral cascadetransport turbulence model". United States.
doi:10.1016/j.nucengdes.2017.06.001.
@article{osti_1393902,
title = {Wallresolved spectral cascadetransport turbulence model},
author = {Brown, C. S. and Shaver, D. R. and Lahey, R. T. and Bolotnov, I. A.},
abstractNote = {A spectral cascadetransport model has been developed and applied to turbulent channel flows (Reτ= 550, 950, and 2000 based on friction velocity, uτ ; or ReδΜ= 8,500; 14,800 and 31,000, based on the mean velocity and channel halfwidth). This model is an extension of a spectral model previously developed for homogeneous single and twophase decay of isotropic turbulence and uniform shear flows; and a spectral turbulence model for wallbounded flows without resolving the boundary layer. Data from direct numerical simulation (DNS) of turbulent channel flow was used to help develop this model and to assess its performance in the 1D direction across the channel width. The resultant spectral model is capable of predicting the mean velocity, turbulent kinetic energy and energy spectrum distributions for singlephase wallbounded flows all the way to the wall, where the model source terms have been developed to account for the wall influence. We implemented the model into the 3D multiphase CFD code NPHASECMFD and the latest results are within reasonable error of the 1D predictions.},
doi = {10.1016/j.nucengdes.2017.06.001},
journal = {Nuclear Engineering and Design},
number = C,
volume = 320,
place = {United States},
year = {Sat Jul 08 00:00:00 EDT 2017},
month = {Sat Jul 08 00:00:00 EDT 2017}
}

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