Spectral analysis of turbulence in anisothermal channel flows
In very anisothermal turbulent flows, the temperature gradient and turbulence are strongly coupled. The impact of the temperature gradient on turbulent kinetic energy (TKE) balance terms is of particular importance. In this paper, it is investigated using direct numerical simulations and large eddy simulations of a fully developed anisothermal channel flow. A low Mach flow at two turbulent Reynolds number (180 and 395) is considered. The temperatures of the two channel walls are 293 K and 586 K. Comparison with isothermal channel flows are carried out. The turbulent kinetic energy spectral evolution equation is established and is decomposed into the three distinctive mechanisms: production, nonlinear transfer and viscous effects. The decomposition isolates the terms that vanish in the isothermal case, namely purely anisothermal effects. The behavior of each term is first discussed in the isothermal case. The alteration of the TKE balance terms with the temperature gradient is then analysed relatively to the Reynolds number variation. The thermal gradient effect is characterized by the combined effect of local Reynolds number variation and the complex interaction between temperature and turbulence. Finally, the purely anisothermal contribution moves the energy from the hot side to the cold side and accounts for near 10%more »
 Authors:

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 Univ. of Perpignan (France). Processes, Materials and Solar Energy (PROMESCNRS); Univ. of Orléans (France). National Inst. of Applied Sciences Centre Val de Loire (INSA CVL). PRISME Lab.
 Univ. of Perpignan (France). Processes, Materials and Solar Energy (PROMESCNRS)
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Publication Date:
 Report Number(s):
 LLNLJRNL752027
Journal ID: ISSN 00457930; 933481
 Grant/Contract Number:
 AC5207NA27344; 2014c20142a5099; 2015c20152a5099
 Type:
 Accepted Manuscript
 Journal Name:
 Computers and Fluids
 Additional Journal Information:
 Journal Volume: 151; Journal ID: ISSN 00457930
 Publisher:
 Elsevier
 Research Org:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of Perpignan (France); Univ. of Orléans (France)
 Sponsoring Org:
 USDOE; Alternative Energies and Atomic Energy Commission (CEA) (France); Big National Equipment Intensive Computing (GENCI) (France)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 47 OTHER INSTRUMENTATION; turbulence; temperature; numerical simulations; spectral analysis; low mach number flows
 OSTI Identifier:
 1465284
Aulery, Frederic, Dupuy, Dorian, Toutant, Adrien, Bataille, Françoise, and Zhou, Ye. Spectral analysis of turbulence in anisothermal channel flows. United States: N. p.,
Web. doi:10.1016/j.compfluid.2016.06.011.
Aulery, Frederic, Dupuy, Dorian, Toutant, Adrien, Bataille, Françoise, & Zhou, Ye. Spectral analysis of turbulence in anisothermal channel flows. United States. doi:10.1016/j.compfluid.2016.06.011.
Aulery, Frederic, Dupuy, Dorian, Toutant, Adrien, Bataille, Françoise, and Zhou, Ye. 2016.
"Spectral analysis of turbulence in anisothermal channel flows". United States.
doi:10.1016/j.compfluid.2016.06.011. https://www.osti.gov/servlets/purl/1465284.
@article{osti_1465284,
title = {Spectral analysis of turbulence in anisothermal channel flows},
author = {Aulery, Frederic and Dupuy, Dorian and Toutant, Adrien and Bataille, Françoise and Zhou, Ye},
abstractNote = {In very anisothermal turbulent flows, the temperature gradient and turbulence are strongly coupled. The impact of the temperature gradient on turbulent kinetic energy (TKE) balance terms is of particular importance. In this paper, it is investigated using direct numerical simulations and large eddy simulations of a fully developed anisothermal channel flow. A low Mach flow at two turbulent Reynolds number (180 and 395) is considered. The temperatures of the two channel walls are 293 K and 586 K. Comparison with isothermal channel flows are carried out. The turbulent kinetic energy spectral evolution equation is established and is decomposed into the three distinctive mechanisms: production, nonlinear transfer and viscous effects. The decomposition isolates the terms that vanish in the isothermal case, namely purely anisothermal effects. The behavior of each term is first discussed in the isothermal case. The alteration of the TKE balance terms with the temperature gradient is then analysed relatively to the Reynolds number variation. The thermal gradient effect is characterized by the combined effect of local Reynolds number variation and the complex interaction between temperature and turbulence. Finally, the purely anisothermal contribution moves the energy from the hot side to the cold side and accounts for near 10% of the total process.},
doi = {10.1016/j.compfluid.2016.06.011},
journal = {Computers and Fluids},
number = ,
volume = 151,
place = {United States},
year = {2016},
month = {6}
}