Model of nonstationary, inhomogeneous turbulence
Abstract
Here, we compare results from a spectral model for nonstationary, inhomogeneous turbulence (Besnard et al. in Theor Comp Fluid Dyn 8:1–35, 1996) with direct numerical simulation (DNS) data of a shearfree mixing layer (SFML) (Tordella et al. in Phys Rev E 77:016309, 2008). The SFML is used as a test case in which the efficacy of the model closure for the physicalspace transport of the fluid velocity field can be tested in a flow with inhomogeneity, without the additional complexity of meanflow coupling. The model is able to capture certain features of the SFML quite well for intermediate to long times, including the evolution of the mixinglayer width and turbulent kinetic energy. At shorttimes, and for more sensitive statistics such as the generation of the velocity field anisotropy, the model is less accurate. We propose two possible causes for the discrepancies. The first is the local approximation to the pressuretransport and the second is the a priori spherical averaging used to reduce the dimensionality of the solution space of the model, from wavevector to wavenumber space. DNS data are then used to gauge the relative importance of both possible deficiencies in the model.
 Authors:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Univ. of New Mexico, Albuquerque, NM (United States)
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1331267
 Report Number(s):
 LAUR1529117
Journal ID: ISSN 09354964
 Grant/Contract Number:
 AC5206NA25396
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Theoretical and Computational Fluid Dynamics
 Additional Journal Information:
 Journal Volume: 2016; Journal ID: ISSN 09354964
 Publisher:
 Springer
 Country of Publication:
 United States
 Language:
 English
 Subject:
 42 ENGINEERING; Mathematics
Citation Formats
Bragg, Andrew D., Kurien, Susan, and Clark, Timothy T.. Model of nonstationary, inhomogeneous turbulence. United States: N. p., 2016.
Web. doi:10.1007/s0016201604011.
Bragg, Andrew D., Kurien, Susan, & Clark, Timothy T.. Model of nonstationary, inhomogeneous turbulence. United States. doi:10.1007/s0016201604011.
Bragg, Andrew D., Kurien, Susan, and Clark, Timothy T.. 2016.
"Model of nonstationary, inhomogeneous turbulence". United States.
doi:10.1007/s0016201604011. https://www.osti.gov/servlets/purl/1331267.
@article{osti_1331267,
title = {Model of nonstationary, inhomogeneous turbulence},
author = {Bragg, Andrew D. and Kurien, Susan and Clark, Timothy T.},
abstractNote = {Here, we compare results from a spectral model for nonstationary, inhomogeneous turbulence (Besnard et al. in Theor Comp Fluid Dyn 8:1–35, 1996) with direct numerical simulation (DNS) data of a shearfree mixing layer (SFML) (Tordella et al. in Phys Rev E 77:016309, 2008). The SFML is used as a test case in which the efficacy of the model closure for the physicalspace transport of the fluid velocity field can be tested in a flow with inhomogeneity, without the additional complexity of meanflow coupling. The model is able to capture certain features of the SFML quite well for intermediate to long times, including the evolution of the mixinglayer width and turbulent kinetic energy. At shorttimes, and for more sensitive statistics such as the generation of the velocity field anisotropy, the model is less accurate. We propose two possible causes for the discrepancies. The first is the local approximation to the pressuretransport and the second is the a priori spherical averaging used to reduce the dimensionality of the solution space of the model, from wavevector to wavenumber space. DNS data are then used to gauge the relative importance of both possible deficiencies in the model.},
doi = {10.1007/s0016201604011},
journal = {Theoretical and Computational Fluid Dynamics},
number = ,
volume = 2016,
place = {United States},
year = 2016,
month = 7
}

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