A coarse-grained LES model for turbulent channel flow

N. Hu; H. Liu; Z. S. She; F. Hussain

doi:10.1063/1.3651835

A coarse-grained LES model for turbulent channel flow

N. Hu, H. Liu, Z. S. She, F. Hussain

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

Abstract

A hybrid RANS-LES method based on structural ensemble dynamics (SED) theory is presented, wherein coarse-grained turbulent fluctuation amplitudes are re-normalized using instantaneous values of an order function, i.e. mixing length, in the ensemble-averaged Navier-Stokes (EANS) equation. The re-normalization procedure is applied throughout the channel (at wall friction Reynolds numbers Re_τ=1 050 and 2 000), to evade the common problem of log-layer mismatch. The mean and rms velocity profiles show improved agreement with DNS at very coarse grids (40×49×20 for both Re's). The method dissipates turbulent kinetic energy in the bulk flow, and increases turbulent fluctuations in the buffer region, mimicking the physical forcing of the sub-grid scale term. The results demonstrate the feasibility to reconstruct the unsteady effect of wall-bounded flows constrained by order functions.

Original language	English (US)
Title of host publication	Recent Progresses in Fluid Dynamics Research - Proceedings of the Sixth International Conference on Fluid Mechanics, ICFM VI
Pages	61-65
Number of pages	5
Volume	1376
DOIs	https://doi.org/10.1063/1.3651835
State	Published - Nov 8 2011
Event	Proceedings of the 6th International Conference on Fluid Mechanics: Recent Progresses in Fluid Dynamics Research, ICFM VI - Guangzhou, China Duration: Jun 30 2011 → Jul 3 2011

Other

Other	Proceedings of the 6th International Conference on Fluid Mechanics: Recent Progresses in Fluid Dynamics Research, ICFM VI
Country	China
City	Guangzhou
Period	6/30/11 → 7/3/11

Keywords

channel
hybrid RANS/LES method
large eddy simulation
order functions
structural ensemble dynamics

ASJC Scopus subject areas

Physics and Astronomy(all)

Access to Document

10.1063/1.3651835

Fingerprint Dive into the research topics of 'A coarse-grained LES model for turbulent channel flow'. Together they form a unique fingerprint.

Cite this

Hu, N, Liu, H, She, ZS & Hussain, F 2011, A coarse-grained LES model for turbulent channel flow. in Recent Progresses in Fluid Dynamics Research - Proceedings of the Sixth International Conference on Fluid Mechanics, ICFM VI. vol. 1376, pp. 61-65, Proceedings of the 6th International Conference on Fluid Mechanics: Recent Progresses in Fluid Dynamics Research, ICFM VI, Guangzhou, China, 6/30/11. https://doi.org/10.1063/1.3651835

@inproceedings{4f44e751dcd34f0f8fa73cbeee5a3ef4,

title = "A coarse-grained LES model for turbulent channel flow",

abstract = "A hybrid RANS-LES method based on structural ensemble dynamics (SED) theory is presented, wherein coarse-grained turbulent fluctuation amplitudes are re-normalized using instantaneous values of an order function, i.e. mixing length, in the ensemble-averaged Navier-Stokes (EANS) equation. The re-normalization procedure is applied throughout the channel (at wall friction Reynolds numbers Reτ=1 050 and 2 000), to evade the common problem of log-layer mismatch. The mean and rms velocity profiles show improved agreement with DNS at very coarse grids (40×49×20 for both Re's). The method dissipates turbulent kinetic energy in the bulk flow, and increases turbulent fluctuations in the buffer region, mimicking the physical forcing of the sub-grid scale term. The results demonstrate the feasibility to reconstruct the unsteady effect of wall-bounded flows constrained by order functions.",

keywords = "channel, hybrid RANS/LES method, large eddy simulation, order functions, structural ensemble dynamics",

author = "N. Hu and H. Liu and She, {Z. S.} and F. Hussain",

year = "2011",

month = nov,

day = "8",

doi = "10.1063/1.3651835",

language = "English (US)",

isbn = "9780735409361",

volume = "1376",

pages = "61--65",

booktitle = "Recent Progresses in Fluid Dynamics Research - Proceedings of the Sixth International Conference on Fluid Mechanics, ICFM VI",

note = "Proceedings of the 6th International Conference on Fluid Mechanics: Recent Progresses in Fluid Dynamics Research, ICFM VI ; Conference date: 30-06-2011 Through 03-07-2011",

}

TY - GEN

T1 - A coarse-grained LES model for turbulent channel flow

AU - Hu, N.

AU - Liu, H.

AU - She, Z. S.

AU - Hussain, F.

PY - 2011/11/8

Y1 - 2011/11/8

N2 - A hybrid RANS-LES method based on structural ensemble dynamics (SED) theory is presented, wherein coarse-grained turbulent fluctuation amplitudes are re-normalized using instantaneous values of an order function, i.e. mixing length, in the ensemble-averaged Navier-Stokes (EANS) equation. The re-normalization procedure is applied throughout the channel (at wall friction Reynolds numbers Reτ=1 050 and 2 000), to evade the common problem of log-layer mismatch. The mean and rms velocity profiles show improved agreement with DNS at very coarse grids (40×49×20 for both Re's). The method dissipates turbulent kinetic energy in the bulk flow, and increases turbulent fluctuations in the buffer region, mimicking the physical forcing of the sub-grid scale term. The results demonstrate the feasibility to reconstruct the unsteady effect of wall-bounded flows constrained by order functions.

AB - A hybrid RANS-LES method based on structural ensemble dynamics (SED) theory is presented, wherein coarse-grained turbulent fluctuation amplitudes are re-normalized using instantaneous values of an order function, i.e. mixing length, in the ensemble-averaged Navier-Stokes (EANS) equation. The re-normalization procedure is applied throughout the channel (at wall friction Reynolds numbers Reτ=1 050 and 2 000), to evade the common problem of log-layer mismatch. The mean and rms velocity profiles show improved agreement with DNS at very coarse grids (40×49×20 for both Re's). The method dissipates turbulent kinetic energy in the bulk flow, and increases turbulent fluctuations in the buffer region, mimicking the physical forcing of the sub-grid scale term. The results demonstrate the feasibility to reconstruct the unsteady effect of wall-bounded flows constrained by order functions.

KW - channel

KW - hybrid RANS/LES method

KW - large eddy simulation

KW - order functions

KW - structural ensemble dynamics

UR - http://www.scopus.com/inward/record.url?scp=80355136388&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=80355136388&partnerID=8YFLogxK

U2 - 10.1063/1.3651835

DO - 10.1063/1.3651835

M3 - Conference contribution

AN - SCOPUS:80355136388

SN - 9780735409361

VL - 1376

SP - 61

EP - 65

BT - Recent Progresses in Fluid Dynamics Research - Proceedings of the Sixth International Conference on Fluid Mechanics, ICFM VI

T2 - Proceedings of the 6th International Conference on Fluid Mechanics: Recent Progresses in Fluid Dynamics Research, ICFM VI

Y2 - 30 June 2011 through 3 July 2011

ER -