I.V.Vovk, V.T.Grinchenko, V.S.Malyuga Self-sustained oscillations of the flow in a duct with stenoses |
Applied hydromechanics, Vol. 11 (83) ¹ 4, (2009) |
| The flow of viscous incompressible fluid in a plane duct with two serial stenoses (contractions) is studied by way of the numerical solution of the unsteady Navier-Stokes equations. The algorithm of the numerical computations is based on the finite volume method and employs the TVD schemes for the discretization of the convective terms. The features of the flow in the area between the stenoses are analyzed at various Reynolds number. Specifically, it is shown that within certain limits of the Reynolds number an ensemble of vortex structures develops in the shear layers at the interface between the jet and the cavities (pockets) formed by the stenoses. As a consequence the stable periodic antisymmetric self-sustained oscillations of the velocity profile arise at the outlet of the second stenosis orifice. In principle, those oscillations may serve as an acoustic source in the duct. The dependence of the Strouhal number of the velocity profile oscillations on the Reynolds number is established. |
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KEY WORDS: *** |
| TEXT LANGUAGE: Russian |