|Dopov. Nac. akad. nauk Ukr. 2020, 3:19-27|
A constant interest in the widespread use of layered structures in the creation of modern supersonic aircraft and reusable space transport systems has appeared in recent years, and this trend continues and is currently being activated. The effective bearing capacity of three-layer shell structures with sufficient lightness makes them very useful in various engineering applications. The continuous development of new structural materials leads to increasingly complex structural constructions that require careful analysis. One of the common elements of these shell structures are three-layer spherical shells that are subjected to unsteady loads. In the literature, there are a sufficient number of studies on the dynamics of three-layer shells . However, recently, the creation of special-purpose facilities, etc. leads to the need to develop structural three-layer shell elements with a filler with complicated geometric structure. The dynamic behavior of such shells has not been studied enough. In this paper, the kinematic and static hypotheses are applied to each layer of shells, which increases the general order of the system of equations, but allows a more detailed study of the dynamic behavior of a three-layer structure. The solution to the problem is based on the theory of shells and rods based on the Timoshenko shear model. To derive the equations of oscillations of a three-layer structure non-uniform in thickness, the variational principle of Hamilton—Ostrogradsky stationarity is used. The numerical simulation of the dynamics of a three-layer spherical shell with a discrete inhomogeneous filler is carried out using an explicit finite-difference scheme for integrating the equations. Numerical results of solving some specific problems are presented.
|Keywords: discrete filler, non-stationary load, numerical method., three-layer spherical shell, Timoshenko theory of shells and rods|
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