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Information × Registration Number 0210U003022, 0106U004472 , R & D reports Title Modelling and optimization of unsteady jet and near-wall flows popup.stage_title Head Savchenko Yury Мickolaevich, Registration Date 13-01-2010 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2 Resultes are presented of theoretical research of two-dimensional flows over curvilinear obstacle influenced by superficial tension force with cavity formation. Theoretical estimations of resistance reduction by surface are done on which mixed type of boundary conditions with areas of sliding in the boundary layer were accounted for. Estimation of resistance reduction by supercavitation on vertical wall are obtained. Experimental research of gliding cylinder are conducted for the supercavitating surfaces. Results of computer modelling of supercavitating vehicle dynamics are presented with the use of most complete approximate models for unsteady supercavities. Increase of distance was investigated for supercavitational motion of axisymmentical bodies, analytical formulas are obtained for maximal distance and parameters of optimum body form with different isoperimetic conditions. Results of the water entrance experiments are included for axisymmetrical bodies of special forms with negative pressure gradients on their surface. Complete solutions of nonlinear problems of water entrance for vertical asymmetrical wedge are presented. Results for boundary flows with complex structures in a form of penetrable roughness (PR), conducted both as basic and application problems, are presented. Numerical prognoses were done for cooling performance of large spraying system (SCS) of South-Ukrainian nuclear power plant. Aerotermal performance is based on a new mathematical model of single spray and on an improved mathematical model of droplet flow that takes into account their upward and downward motion and conjugation between internal and external processes of heat exchange and evaporation. Previous study of vortices behind penetrable inserts in ducts was completed with consideration of their stability. Generalization of the plain PR models was initiated for arbitrary duct cross-sections (rectangle, triagle, circular as well); some dependences of hydraulic resistance for them were found with account of PR height and density. Product Description popup.authors Власенко Ю.Д. Гаєв Є.О. Нестерук І.Г. Семененко В.М. Семенов Ю.А. popup.nrat_date 2020-04-02 Close