Abstract
A novel notion of turbulent structure—the local cascade structure—is introduced to study the convection phenomenon in a turbulent channel flow. A space–time cross-correlation method is used to calculate the convection velocity. It is found that there are two characteristic convection speeds near the wall, one associated with small-scale streaks of a lower speed and another with streamwise vortices and hairpin vortices of a higher speed. The new concept of turbulent structure is powerful to illustrate the dominant role of coherent structures in the near-wall convection, and to reveal also the nature of the convection—the propagation of patterns of velocity fluctuations—which is scale-dependent.
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References
Zaman Q., Hussain F.: Taylor’s hypothesis and large-scale coherent structures. J. Fluid Mech. 112, 379–396 (1981)
Kim J., Hussain F.: Propagation velocity of perturbations in turbulent channel flow. Phys. Fluids 5(3), 695–706 (1993)
Romano G.P.: Analysis of two-point velocity measurements in near-wall flows. Exp. Fluids 20, 68–83 (1995)
Krogstad P.A., Kasperson J.H., Rimestad S.: Convection velocities in a turbulent boundary layer. Phys. Fluids 10(4), 949–957 (1998)
Khoo B.C., Chew Y.T., Teo C.J.: Turbulence time scale, convective velocity and spectra in the viscous sublayer. Exp. Fluids 31, 494–505 (2001)
Quadrio M., Luchini P.: Integral space-time scales in turbulent wall flows. Phys. Fluids 15(8), 2219–2227 (2003)
Hussain F., Clark A.R.: Measurements of wavenumber-celerity spectrum in plane and axisymmetric jets. AIAA J. 19(1), 51–55 (1981)
Davidson P.A.: Turbulence. Oxford University Press, Oxford (2004)
Kline J., Reynolds C., Schraub A., Runstadler W.: The structure of turbulent boundary layer. J. Fluid Mech. 30(4), 741–773 (1967)
Robinson S.K.: Coherent strutures in the turbulent boundary layer. Annu. Rev. Fluid Mech. 23, 601–639 (1991)
Kim J., Moin P., Moser R.: Turbulence statistics in fully developed channel flow at low Reynolds number. J. Fluid Mech. 177, 133–166 (1987)
Xu C., Zhang Z.: Origin of high kurtosis levels in the viscous sublayer. Direct numerical simulation and experiment. Phys. Fluids 8(7), 1938–1944 (1996)
Jeong J., Hussain F., Schoppa W., Kim J.: Coherent structures near the wall in a turbulent channel flow. J. Fluid Mech. 332, 185–214 (1997)
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This project was supported by the National Natural Science Foundation of China (10572004 and 90716008).
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Cao, Y., Chen, J. & She, Z. The nature of near-wall convection velocity in turbulent channel flow. Acta Mech Sin 24, 587–590 (2008). https://doi.org/10.1007/s10409-008-0182-x
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DOI: https://doi.org/10.1007/s10409-008-0182-x