Nearest Wall Flows – the Genuine Turbulence
Journal Title: INCAS BULLETIN - Year 2017, Vol 9, Issue 3
Abstract
Traditionally, the wall-bounded flows are boundary-layer like flows where the velocity gradients normal to the wall u/y are very large and the velocity monotonously increases from zero to about the velocity free flow, Ue = 0.99 U. However, the instabilities of flow, resulting from the reaction of the solid boundary against onset of flow, originate in the nearest-wall region where the mean velocity varies around of the velocity Ub = 1m/s constituting the wavy microflow field dominated by the boundary vorticity-viscosity mutual changes. The paper is aiming at presenting the main features of the microflow field and a new vision of the turbulence phenomenon illustrated trough canonical boundary-layer flows.
Authors and Affiliations
Horia DUMITRESCU, Vladimir CARDOS
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