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Information × Registration Number 0219U004959, 0118U003442 , R & D reports Title Investigation of applied issues of application of supercavitating, jet and unseparated flows for high-speed underwater motion popup.stage_title Head Savchenko Yurii Nikolaevich, Доктор технічних наук Registration Date 17-12-2019 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2 A technique of conducting experiments on the entrance of bodies into water at small angles of the trajectory inclination is presented. Methods for measuring the lower and upper contours of the supercavity boundaries, estimating the size, volume of the supercavity, and hydrodynamic forces as the disk enters the water at the angles of trajectory from 5 to 30 degrees are proposed. Methods of calculation of stationary and non-stationary motion of supercavitating (SC) vehicle with conical cavitators are developed, examples of calculations are given and efficiency of their use for control is investigated. It is shown that cone cavitators with an vertex angle of less than 65.4 degrees are more effective for control than equivalent disk ones, and their efficiency increases rapidly with decreasing vertex angle. The maneuvering of the SK model in depth and at the rate by tilting the cone cavitators with different vertex angles is considered. The effectiveness of the automatic depth stabilization system for the cone cavitator model has been confirmed. Preliminary results of a simulation of the flow around a specially profiled UA-2 body of revolution using computer hydromechanics (CFD) techniques are presented. The applied stationary laminar model of incompressible fluid on both two-dimensional and three-dimensional grids indicates an attached flow pattern for sufficiently high ambient flow velocities. When the Reynolds number decreases (approximately, to values less than 13000), the inseparable flow pattern disappears. Obtaining reliable drag results and improved convergence require further refinement of the calculation grids. The solution of the nonlinear problem of the flow around a body of arbitrary shape under a free surface was obtained. The solution is presented in the form of analytical expressions for complex velocity and derivatives of complex potential. These expressions contain explicitly the modulus and argument of complex velocity on a free surface, as well as tangent to the body as a function of a parametric variable. An integro-differential equation was obtained to determine these functions from boundary conditions.5481 Product Description popup.authors Іванюк Володимир Філімонович Власенко Юрій Дмитрович Каширіхін Леонід Петрович Кисельов Тарас Петрович Козенко Олег Миколайович Кудибин Ігор Богданович Манова Зінаїда Іванівна Наумова Олена Іонівна Нестерук Ігор Георгійович Савченко Георгій Юрійович Савченко Юрій Миколайович Семененко Володимир Миколайович Семенов Юрій Асаф'євич Чичик Петро Дмитрович popup.nrat_date 2020-04-02 Close