N.S.Gorodetska, V.I.Nikishov, L.V.Tkachenko The numerical modeling of the development of the Taylor-Gertler's vortices in unsteady Couette's flow. 2. Different parameters of entering the disturbances |
Applied hydromechanics, Vol. 14 (86) ¹ 3, (2012) |
| The results of numerical simulation of a regular perturbation vorticity development in a boundary layer over a concave surface are presented. The boundary layer is formed over the inner surface of the external cylinder after its stop in a circular Couette flow between two rotating cylinders. It is shown that a noticeable drop of the energy of regular vertical perturbations introducing in flow occurs at initial time. The shape of the perturbations was close to Gertler's longitudinal vortices. The drop is connected with the adaptation of vortices to the peculiarities of the flow. The greater is the initial perturbations energy, the greater it is the drop of disturbances energy. In time, the vortical disturbances develop and their energy increases, and nonlinear effects become important. The influence of nonlinear effects appears earlier for perturbations with greater energy. This influence causes a deviation of the growth energy curves from the exponential law. |
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KEY WORDS: numerical modeling, boundary layer, vortical structure, perturbations energy |
| TEXT LANGUAGE: Russian |