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Information × Registration Number 0218U007403, 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, Registration Date 11-12-2018 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2 The rapid vertical motion of a circular bracket that strikes the wall of a cylindrical cavity is investigated. The nonlinear hydrodynamic problem was solved by applying the current potential and the integral hodograph method and reduced to a system of integral and integro-differential equations. The results of calculations are presented. The non-monotonic behavior of the coefficient of the virtual mass for different arc corners is revealed. This study gives an opportunity to evaluate the impulse forces acting on supercavitating (SC) vehicles that move at high speeds within the supercavity and are necessary to predict the overall dynamics of high-speed supercavitating vehicles. The method of finding the equilibrium values of motion parameters (balancing) of the SC apparatus in a non-glancing mode is developed, when for a full or partial compensation of the weight of the device a pair of identical horizontal steering wheels penetrating from the cavity into water is used. It is shown that the longitudinal motion of the SC apparatus, balanced by means of horizontal steering wheels, in a mode without planning, in contrast to its movement in the mode of planning in the cavity, is stable "in small". In a mixed mode, the complex dynamics of the SC apparatus was detected, which significantly depends on the initial value of the pitch angle. Using aerodynamic experiments it has been shown that on a solid body of a rotation of a special shape (similar to a dolphin body), it is possible to avoid the separation of the boundary layer without any active flow control methods. Measurement of static pressure and visualization using oil flow were used. The static pressure distributions and the results of visualization using oil flow for the three values of the angle of attack are given. The results of experiments show that at zero angle of attack the flow is attached and laminar. Product Description popup.authors Іванюк Володимир Філімонович Власенко Юрій Дмитрович Каширіхін Леонід Петрович Кисельов Тарас Петрович Козенко Олег Миколайович 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