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Information × Registration Number 0221U104324, 0119U100042 , R & D reports Title Development of methods for studying the strength and stability of thin-walled shells and elastic solids with a liquid under the influence of various types of dynamic loads popup.stage_title Head Shevchenko Volodymyr P., Доктор фізико-математичних наук Registration Date 13-03-2021 Organization Vasyl' Stus Donetsk National University popup.description2  The oscillations of a rectangular plate in an ideal fluid are considered, taking into account different ways of fixing its contours. It is shown that for two supported or free circuits the frequency equation splits into two equations describing asymmetric and symmetric frequencies, and for mixed methods of fastening two loops the frequency equation no longer splits into odd and even frequencies. For all mixed methods of fixing circuits, it is necessary to use numerical studies of the obtained frequency equations. The stability of oscillations of the elastic bottom of a rectangular channel in the form of a membrane and an ideal liquid is investigated. An approximate formula for high frequencies, approximate and exact stability conditions for the joint oscillations of the membrane and the liquid are obtained. It is shown that the approximate values of the critical tension for asymmetric and symmetric frequencies are underestimated by 4/5 and 0.818 times, respectively. The frequency equation of natural oscillations of a heavy ideal two-layer incompressible fluid in a rigid circular cylindrical tank with elastic bases in the form of thin circular fixed plates is investigated. Axisymmetric and asymmetric oscillations of fluid and plates and various limit cases of degeneration of plates into membranes, into absolutely rigid plates, as well as the case of absence of the upper plate are considered. It is shown that the frequency spectrum of compatible asymmetric oscillations of elastic bases and two-layer ideal fluid consists of three sets of frequencies corresponding to the oscillations of the upper and lower elastic bases and oscillations of the inner interface, and the frequency spectrum of compatible symmetric oscillations consists of the same three sets of frequencies. for asymmetric oscillations, and the additional frequency of oscillations of the liquid column as a whole. The frequency spectrum was analyzed analytically and numerically on the example of a homogeneou Product Description popup.authors Vetrov Oleg S. Kononov Yuriy M. Lymar Oleksandr O. Sviatenko Iaroslav I. popup.nrat_date 2021-03-17 Close