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Information × Registration Number 0214U000379, 0113U002290 , R & D reports Title Development of theory and methods for analysis of elastic and vibroimpact systems vibrations under stochastic and impact loadings popup.stage_title Head Solovey Nickolay, Registration Date 25-03-2014 Organization Scientific - research complex of the Kyiv National University of Construction & Architecture popup.description2 The theoretical basis for parameter continuation method was elaborated. We have used this method together with method of periodical solutions construction for essentially nonlinear systems and together with impact simulation by nonlinear contact Hertz's force. These theory and technique were intended for investigations of dynamic behaviour of two-mass two-degree-of-freedom vibroimpact system. It has given the possibility to create the amplitude-frequency characteristics, to fulfil stability analysis for T-periodical oscillation motion. It has allowed to construct the spectral density and Poincare sections which are necessary for complicated vibration modes analysis. Analysis of vibroimpact system dynamic modes has been fulfilled. We have created the amplitude-frequency characteristics and have found the instability zones. We have searched the regular and chaotic vibroimpact modes and the periodic regimes with big impact numbers. Such phenomenon causes "strange attractors" appearance. We have investigated the influence of external loading parameters at contact force dynamic behaviour. An effective approach to the evaluation of the singular boundary integrals which occur in 2-D solids dynamics was developed. The essence of the approach lies in the power series expansion of the integral equations kernels components yielding to reduction of the integrands singularity order. The problem of the 2-D elastic solid with two cylindrical holes transient dynamics was studied using developed techniques. Reduced models of stochastic parametric vibrations of elastic systems with regard to their previous states was constructed on the base of the finite element method, generalized coordinates method, asymptotic method and functional approach. Stochastic stability problem was formulated in the average for the moment functions of the phase coordinates of the first order. The stability of stochastic parametric vibrations of the system with one degree of freedom with regard to its previous states was investigated by the 7-stages 5-order continuous Runge- Kutta method and nested formulas Dormand-Prince. The mathematical modeling of the dynamics of complex shell structure under the action of uniformly distributed load on the weight of the liquid. Estimated discrete dynamical model of the design is builted using finite element methods and possible displacements that are implemented in the software package NASTRAN. Modal analysis loaded structure using the Lanczos method is performed. The effect of pressure on the natural oscillations of a complex shell structure is assessed. The frequency and form of natural oscillations of structures under the weight of liquid in various capacities are compared. Product Description popup.authors Бубенчикова В.Г. Ворона Юрій Володимирович Козак А.А. Костіна Олена Володимірівна Лук'янченко Ольга Олексіївна Погорелова Ольга Семенівна Постнікова Тетяна Георгіївна popup.nrat_date 2020-04-02 Close