According to a model of the turbulent boundary layer that we propose, in the absence of external turbulence the intermediate region between the viscous sublayer and the external flow consists of two sharply separated self-similar structures. The velocity distribution in these structures is described by two different scaling laws. The mean velocity u in the region adjacent to the viscous sublaye...

Statistics of the streamwise velocity component in fully-developed pipe flow are examined for Reynolds numbers in the range 5.5 x 10 < Reo < 5.7 x 10. The second moment exhibits two maxima: one in the viscous sublayer is Reynoldsnumber dependent while the other, near the lower edge of the log region, is also Reynolds-number dependent and follows roughly the peak in Reynolds shear stress. The be...

We demonstrate that the processing of the experimental data for the average velocity profiles obtained by J. M. ¨ Osterlund 1 ] was incorrect. Properly processed these data lead to the opposite conclusion: they confirm the Reynolds-number-dependent scaling law and disprove the conclusion that the flow in the intermediate ('overlap') region is Reynolds-number-independent. 1 In a recent issue of ...

We demonstrate that the processing of the experimental data for the average velocity profiles obtained by J. M. ¨ Osterlund (www.mesh.kth.se/∼jens/zpg/) presented in [ 1 ] was incorrect. Properly processed these data lead to the opposite conclusion: they confirm the Reynolds-number-dependent scaling law and disprove the conclusion that the flow in the intermediate ('overlap') region is Reynolds...

Direct numerical simulations of wall-bounded flow reveal that turbulence production can be suppressed by a transverse traveling wave. Flow visualizations show that the near-wall streaks are eliminated, in contrast to other turbulence-control techniques, leading to a large shear stress reduction. The traveling wave can be induced by a spanwise force that is confined within the viscous sublayer; ...

Title of thesis: VELOCITY TRANSFORMATION FOR COMPRESSIBLE WALL TURBULENCE WITH HEAT TRANSFER Andrew Trettel, Master of Science, 2015 Thesis directed by: Professor Johan Larsson Department of Mechanical Engineering A transformation is derived that removes the effects of variable properties from wallbounded turbulent flows. The transformation derives from the logarithmic velocity profile and the ...

A processing of recent experimental data by Nagib and Hites [Nagib, H. & Hites, M. (1995) AIAA paper 95-0786, Reno, NV) shows that the flow in a zero-pressure-gradient turbulent boundary layer, outside the viscous sublayer, consists of two self-similar regions, each described by a scaling law. The results concerning the Reynolds-number dependence of the coefficients of the wall-region scaling l...

Using theoretical and computational methods we obtain these findings: 1) In micro-confined high-pressure transcritical turbulence, higher than typical levels of vorticity are observed in the viscous sublayer; 2) Flow topologies from far-wall regions vicinity supercritical gas-like wall; 3) Tube-like flow motions favored at scales comparable to density-gradient scale, resulting a smaller number ...