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Information × Registration Number 0226U001546, (0123U100514) , R & D reports Title Synergetics of the vortex state of gradient multiphase flows popup.stage_title Дослідження фізичних механізмів виникнення природних вихрових явищ та пошук способів їх штучного відтворення Head Voropaiev Hennadii О., д.ф.-м.н. Registration Date 27-01-2026 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description1 Construction of a model of the vortex state of gradient and multiphase flows, the vortex structure of which is considered as an open system of interacting components, which allows both the exchange of energy of the system as a whole with the external environment, and the non-linear redistribution of energy between its components, depending on the flow conditions and the structure of the environment. popup.description2 The features of the interrelationship between the Reynolds number, the viscosity gradient in the boundary layer, and the geometric parameters of partial surface development were characterized. A comparison of the scales and characteristics of vortex formations was performed for different flow velocities and thermal regimes. The influence of introducing a corrugated insert at various distances from the pipe inlet and for different cavity lengths on the formation and parameters of vortex structures was analyzed. A comprehensive study of the boundary-layer vortex structure formed during the flow of a viscous incompressible fluid over a flat surface was conducted, depending on the parameters of an initiated local wave disturbance on the wetted surface. The regularities of the formation and downstream development of the boundary-layer vortex structure were determined for different values of amplitude, phase velocity, wavelength, size of the initiation region, and the shape of the traveling-wave front on the surface. The measurement methodology and the experimental setup for PIV measurements of the velocity field in the near wake behind a rectangular wing model (L = 200 mm, b = 100 mm), with and without bent leading-edge bumps, as well as Δ-shaped vortex generators, were improved. Parametric experimental TR-PIV studies were carried out to assess the reliability of velocity distribution measurements in the near wake behind the rectangular wing model for different free-stream velocities (V = 5–45 m/s) over a range of angles of attack covering both attached and separated flow regimes (α = 0°–15°), without and with ellipsoidal leading-edge protuberances of various lengths (l = 5–15 mm). The aerodynamic effectiveness of bent leading-edge bumps was convincingly demonstrated, as well as the advantage of their small length (5–7% of the chord), both in terms of sufficiently high efficiency and reduced additional drag caused by the generation of a vortex system. Product Description popup.authors Shkvar Yevgeniy Oleksiyovych Korobov Vitalii I Sirosh Olena O. Zagumennyi Iaroslav V Dymytriieva Nataliia F. Paramonov Yuriy O. Baskova Oleksandra О. Filonov Vladislav Vitaliyovych Rozumnyuk Nataliya Vjacheslavivna popup.nrat_date 2026-01-27 Close