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Information × Registration Number 0223U001238, 0119U100255 , R & D reports Title Investigation of the effect of motion non-stationary and the environment non-isotermicity on the formation of vortex structures in the flow popup.stage_title Head Voropaev Genadiy O., Доктор фізико-математичних наук Registration Date 26-01-2023 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2 There was numerically investigated the influence of geometry of paired elongated dimples located at an angle to each other on a flat streamlined surface or in a rectangular channel wall on generation and parameters of vortical motion. The effect of dimples on the additional drag of the streamlined surface and thermal efficiency of the dimple topography in heat exchangers was determined; it was shown that the purposeful variation of the corresponding parameters of dimples allows improving the overall efficiency of the profiled surface. Experimental studies of the generation of vortical structures inside the system of oval dimples on the hydraulically smooth plate and their effect on the wall pressure pulsations field have been conducted. It was established that levels of wall pressure pulsations, which corresponded to the frequencies of the of vortex structures emission from the oval dimple, increased and moved in the high-frequency range with an increase in the flow rate. In the power spectral densities of pressure pulsations at transitional and turbulent flow regimes tonal components were observed at frequencies of the vortex structures emission, which were generated inside and thrown out the dimples. The processes of vortex formation around wing profiles were studied, a method was developed for controlling the flow separation by performing active rotational-oscillating movements of the wing in the flow of viscous incompressible fluid that allows obtaining hydrodynamic characteristics of fixed or unsteady moving profiles of arbitrary shapes, to determine local flow separations, the magnitude of the generated vorticity, the structure of vortex wake depending on the geometry, frequency and amplitude of the profile fluctuations. There were determined characteristics of flow around blunt bodies oscillating under action of pressure fluctuation due to the generated vortical systems. Product Description popup.authors Baskova Oleksandra О. Voskobiinyk Andrii V. Dymytriieva Nataliia F Zahumennyi Iaroslav V. Korobov Vitalii I Paramonov Yuriy O. Rozumnyuk Natalia V. Shkvar Eugene O. popup.nrat_date 2023-01-26 Close