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Information × Registration Number 0207U002817, 0106U002530 , R & D reports Title The investigation of the longitudinal vortex structures on a curveliniar surface popup.stage_title Head Zagumenniy Yaroslav Victorovich, Registration Date 19-02-2007 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2 The hydrodynamic characteristics of bodies of complicated forms that are streamlined with a turbulent viscous flow are calculated by means of the devised numerical method in the frame of mathematical model which takes into account the influence of coherent structure scales in a boundary layer on the mechanism of redistribution and transfer of turbulent energy. On the basis of the devised method the 3D problem on development of the boundary layer over an infinitely thin curveliniar surface under its streamline with the undisturbed flow of viscous compressible fluid is solved. The influence of the flow velocity, the radius of curvature as well as the presence of discrete heating of the streamlined surface on the existance, dimensions and intensity of the longitudinal vortex structures in a boundary layer over concave and convex surfaces is studied. On the conducting of the experiments the Goertler vortex were registered under the nozzle of the vortex chamber and in the boundary layer over convex surface of the fornicated plate moving along the curved trajectory. Its location, Goertler numbers, the integral and spectral characteristics of the velocity field were determined on the basis of the improved procedure of integral and local characteristics measurement with the statistic and correlation analysis of measured values. The theoretical and experimental results analysis allows to determine the dependencies of vortex systems scales and intensity on both velocity and properties of the flow, curvature of the surface and dynamic integral characteristics of streamlined bodies. The obtained results give new knowledge about the structure of turbulent flows over bodies with curveliniar surfaces and can be used in the elaboration of new methods of coherent vortex structures generation and intensification in the wall zone of the flow with the purpose of both energy loss decrease and drag reduction on conservation of fair speeds of movement. Product Description popup.authors popup.nrat_date 2020-04-02 Close