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Information × Registration Number 0223U000122, 0121U111811 , R & D reports Title Investigation of the effect of Prandtl numbers variability on the the secondary vortex structure stability in the near-wall region popup.stage_title Head Baskova Oleksandra О., Кандидат технічних наук Registration Date 03-01-2023 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2  The object of research is thermohydraulic processes in internal flows at variable Prandtl numbers. The purpose of scientific research: to establish the regularities of the development of vortex structures, which are artificially generated in the boundary layer due to the presence of centrifugal effects, taking into account thermal processes in liquids. Research methods: numerical experiment. The relevance of the work: the results of studies of the effect of non-isothermality on the formation of a vortex structure will allow us to develop such a geometry of the development of the heat exchange surface, under which it will be possible to maximally intensify the heat exchange with minimal hydraulic losses. At the second stage of the works, the influence of the geometric parameters of the corrugated insert on the intensity of heat exchange in its wake was analyzed. The relationship between the location of the corrugation in the insert and the formation of the vortex structure in the deepening of the corrugation was revealed. The degree of influence of the geometric parameters of corrugation deepening on the structure of vortex formations was evaluated. The peculiarities of the distribution of the frictional stress on the heat flow along the surface of the corrugation recess, depending on its location in the insert and the geometric parameters of the recess, and the structure of the flow in the wake of the corrugated insert were analyzed. On the basis of the conducted numerical modeling, the peculiarities of the formation of the vortex structure of the flow in the initial section of the pipe with a twisted corrugated insert at the limiting transition Reynolds number were revealed in comparison with the axisymmetric problem under the same limiting conditions. The value of heat exchange intensification up to 1.2 times with an increase in hydraulic resistance up to 7% was obtained. A series of numerical experiments was conducted to study the effect of the vortex structure Product Description popup.authors Baskova Oleksandra О. Rudnytska Maria Oleksandrivna popup.nrat_date 2023-01-03 Close