TY - JOUR
T1 - Model for propagation speed in turbulent channel flows
AU - Pei, J.
AU - Chen, J.
AU - She, Z. S.
AU - Hussain, F.
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/10/10
Y1 - 2012/10/10
N2 - The propagation speed V c of the streamwise velocity fluctuations u ′ in turbulent channel flows is calculated using direct numerical simulation (DNS) data at four Mach numbers (M=0, 0.8, 2.0, and 3.0). The profiles of V c are shown to display remarkable similarity at different M. Quantitative models are developed based on a statistical structure called Velocity-Vorticity Correlation Structure (VVCS), defined as the vorticity region most correlated to velocity fluctuations at a fixed location. Good agreement with DNS-measured propagation velocities is obtained throughout the channel and for all M. The result confirms earlier speculation that the near-wall propagation is due to an advection by coherent vortex structures, and validates the concept of the VVCS.
AB - The propagation speed V c of the streamwise velocity fluctuations u ′ in turbulent channel flows is calculated using direct numerical simulation (DNS) data at four Mach numbers (M=0, 0.8, 2.0, and 3.0). The profiles of V c are shown to display remarkable similarity at different M. Quantitative models are developed based on a statistical structure called Velocity-Vorticity Correlation Structure (VVCS), defined as the vorticity region most correlated to velocity fluctuations at a fixed location. Good agreement with DNS-measured propagation velocities is obtained throughout the channel and for all M. The result confirms earlier speculation that the near-wall propagation is due to an advection by coherent vortex structures, and validates the concept of the VVCS.
UR - http://www.scopus.com/inward/record.url?scp=84867476234&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84867476234&partnerID=8YFLogxK
U2 - 10.1103/PhysRevE.86.046307
DO - 10.1103/PhysRevE.86.046307
M3 - Article
AN - SCOPUS:84867476234
SN - 1539-3755
VL - 86
JO - Physical Review E - Statistical, Nonlinear, and Soft Matter Physics
JF - Physical Review E - Statistical, Nonlinear, and Soft Matter Physics
IS - 4
M1 - 046307
ER -