TY - GEN
T1 - Mach number dependence of near wall structure in compressible channel flows
AU - Pei, J.
AU - Chen, J.
AU - She, Z. S.
AU - Hussain, F.
PY - 2011
Y1 - 2011
N2 - A newly developed statistical correlation structure is used to analyze compressible channel flows up to M=3.0. Using velocity-vorticity correlation structure (VVCS), the Mach number dependence of the characteristic scales of near wall structure are analyzed. The detailed results show that the length scale and the spanwise spacing of VVCS exponentially increase with Mach number in the near wall region. For example, for VVCSuωx, the length scale of the statistical streamwise structure is Lx uωx=e6.5+M/2.8+(M/4.1)2, and spacing between the structure is Dxuωx=60eM/2.2+13.3, where the parameters 2.8, 4.1 and 2.2 are characteristic Mach numbers to be explained further. The geometrical features of the statistical structure are consistent with the observations of Coleman et al., and it is also argued that the quantitative relationship between the characteristic scales of VVCS and Mach number is important to consider in performing numerical computation of compressible flows. This study also suggests that a set of geometrical structures should be invoked for modeling inhomogeneous compressible shear flows.
AB - A newly developed statistical correlation structure is used to analyze compressible channel flows up to M=3.0. Using velocity-vorticity correlation structure (VVCS), the Mach number dependence of the characteristic scales of near wall structure are analyzed. The detailed results show that the length scale and the spanwise spacing of VVCS exponentially increase with Mach number in the near wall region. For example, for VVCSuωx, the length scale of the statistical streamwise structure is Lx uωx=e6.5+M/2.8+(M/4.1)2, and spacing between the structure is Dxuωx=60eM/2.2+13.3, where the parameters 2.8, 4.1 and 2.2 are characteristic Mach numbers to be explained further. The geometrical features of the statistical structure are consistent with the observations of Coleman et al., and it is also argued that the quantitative relationship between the characteristic scales of VVCS and Mach number is important to consider in performing numerical computation of compressible flows. This study also suggests that a set of geometrical structures should be invoked for modeling inhomogeneous compressible shear flows.
KW - channel flow,turbulent structure
KW - compressibility effects
KW - velocity-vorticity correlations
UR - http://www.scopus.com/inward/record.url?scp=80355136415&partnerID=8YFLogxK
U2 - 10.1063/1.3651859
DO - 10.1063/1.3651859
M3 - Conference contribution
AN - SCOPUS:80355136415
SN - 9780735409361
T3 - AIP Conference Proceedings
SP - 146
EP - 148
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 -