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Information × Registration Number 0225U000639, (0123U100908) , R & D reports Title Modeling and development of methods for calculating the rational functioning of constructional elements and systems of various purposes under complex loads popup.stage_title Математичне моделювання та розвиток методів аналітично-числового аналізу складних систем з структурованими неоднорідностями та змінними параметрами керування. Head Andriichuk Mykhailo I., Доктор технічних наукKushnir Roman M., д.ф.-м.н. Registration Date 15-01-2025 Organization Institute of Applied Problems of Mechanics and Mathematics named after Ya. S. Pidstryhach of the National Academy of Sciences of Ukraine popup.description1 The purpose of the work is mathematical modeling and development of methods of analytical and numerical research of large-sized thin-walled structures of modern rocket and space technology and targeting systems, as well as constructional elements consisting of composite, functional-gradient and structured materials under various types of complex loads to ensure their optimal and rational functioning. popup.description2 At the second stage, the following results were obtained: 1. Mathematical models and boundary-element methods were developed to calculate the parameters of wave scattering by periodic thin-walled inhomogeneities in a three-dimensional elastic matrix, taking into account the influence of the piezoelectric wave generation mechanism. 2. Mathematical models and a zero-field method were developed to describe the response to wave loading of two-dimensional elastic plates with single and periodic inhomogeneities. 3. The orientation calculation and numerical analysis of the reliability of satellite stabilization under the action of external disturbances were performed and the conditions of asymptotic stability of uniform rotation of an elastic solid with an ideal fluid were obtained. 4. Models of the wave loading problem of elastic matrix with three-periodic cascades of equidistant planes with arrays of disk obstacles have been developed, and in the problems with disk piezoceramic inserts, by taking into account the correlation coefficients of the manifestation of piezoelectric effects. 5. The numerical methods to solve obtained integral equations based on collocations and expansions in wave harmonics have been developed with their testing on the determining the distributions of wave fields of displacements and stresses in elastic systems with single and periodic lattices of non-canonical scatterers. 6. The localization zones and focusing directions of wave scattering, stiffness and grating design for non-orthogonal gratings, cascades with a variable number of periodic grids and chains of scatterers were established. 7. The model of quasi-optical focusing system was generalized to three-dimensional case. An algorithm for calculating its directivity pattern (DP) and optimizing the parameters of separate elements was developed. Numerical experiments were carried out to determine the optimal system parameters that ensure the formation of DP with desired characteristics. Product Description popup.authors Yevhenieva Yevheniia O. Andriichuk Roman М. Drobenko Bohdan D. Zhbadynskyi Ihor Ya. Zuiev Oleksandr L. Kalosha Yuliia I. Kononov Yurii M. Kunets Yaroslav I. Marchuk Mykhailo V. Matus Valerii V. Mykhaskiv Viktor V. Pakosh Vira S. Tkachuk Viktor P. Tokovyi Yurii V. Khom"iak Mykola M. Shevchuk Viktor A. popup.nrat_date 2025-01-15 Close