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Information × Registration Number 0209U002514, 0106U002862 , R & D reports Title Neosesymmetric resonance vibrations and disipative warming-up of the physically nonlinear thin-walled elements in the fixed-frequency approaching popup.stage_title Head Sichko Viktor Mihaylovich, Registration Date 16-02-2009 Organization Mickolaev V.O.Suhomlinsksiy Stated University popup.description2 Object of research: foliated thin-wall elements made of physically non-linear dissipative materials with olisctributed piezoelectric sensor sensors and actuators. Aim of research: development of simplified combined theory of thermomechanical behavior of physically non-linear thin-wall elements made dissipative materials at harmonic load in one-frequency approximation; organization of non-linear marginal problems and research of main conformities of quazistatic and dynamic thermomechanical behavior of homogeneous and heterogeneous elements of construction. With the use of the theory plasticity, theory of plasticity with linear strengthening, modified fluidity theories and models of materials with microplate deformations, models of non-elastic behavior of passive materials with dissipation of harmonic strain have been developed. During such model development the main hypohesis about monoharmony of mechanical processes which leads to complex characteristic conception has been used. Non-linear determiningequations which combine strains and deformations are the same as elasticity theory equations with the difference that these equations are complex. Two types of physical non-linearity have been considered. The first one originates from non-linear relationship between dissipative function and deformations and strains, another type of physical non-linearity originates from the relationship between complex characteristics and temperature. State equations for another type of non-linearity are the same as those of elasticity theory, however, mechanical characteristics in them depend on temperature. State equations for dissipative functions of temperature and deformations. Problems dealing with vibrations and dissipative heat of non-elastic bodies of physically non-linear materials at mechanically harmonic load for both types of physical non-linearity have been presented using the mentioned above conception of complex characteristics which is very efficient for modeling of dynamic harmonic processes in mechanics ofdeformed solid body. Dissipative heat is calculated with the help of energy equation which coincides with ordinary equations of thermoconductivity with the heat source which coincides with dissipative function. Using such problem organization and classical Kirhgoff-Liava hypotheses and specified hypotheses of Timoshenko type supplemented by hypotheses about temperature distribution adequate to them, models of thermo-mechanical behaviour of thin-wall foliated ebments at harmonic load for both types of physical non-linearity have been developed. In both cases problems result in solving of non-linear marginal problems for complex equation withpartial derivatives. For the first type of physical non-linearity in case of mechanical characteristics independent on the temperature the problem comes to the solving of non-linear marginal mechanical problem, calculation of dissipative function and solving of thermoconductivity equation with the known heat source. For another type of physical non-linearity in case of characteristics independent on the temperature - the task is to solve linear marginal dynamic problem of viscoelasticity, dissipative function calculation and solving of thermoconductivity equation with the known heat source. In case of mechanical characteristics heat source. In case of mechanical characteristics of materials dependent on the temperature the problem is to solve conjugated systems of non-linear differential equations in relation to complex displacements and temperature. Product Description popup.authors popup.nrat_date 2020-04-02 Close