USING SOLID-BODY FINITE ELEMENTS IN ANALYSING SHELLS

Abstract

The issues of effectivity of using solid-body FE-models in problems of analyzing shells are considered. A concise review of works on using the FEM in problems of analyzing thin-walled structures is presented. General requirements to coordinate functions in FE-methods when studying general type thin-walled shells are formulated. The main difficulties in formulating effective FE-models for analyzing problems of the theory of plates and shells based on the Kirchhoff - Love hypothesis and Timoshenko-type shear models are examined. Causes of low effectiveness of conventional solid-body FE-models used for analyzing shells are indicated, and possible ways of overcoming them are considered. The effect of FE-discretization parameters on the accuracy of the analyses of shells of various relative thicknesses with the use of three different solid-body FE-models has been assessed, which has made it possible to determine admissible values of FE-discretization parameters of shells for all the considered types of FE-models, as a function of the admissible error in determining stresses. Convergence of solutions in local zones of coupling of cylindrical shells with structural elements of various rigidity has been studied for a number of FE-models, implemented in modern software complexes. The paper presents a version of the model and modeling algorithms for FE-modeling corrosion cracking processes in structural elements loaded by pressure and exposed to aggressive corrosion media. To assess the effectiveness of the present models and algorithms, the failure process of a thin-walled tubular specimen partly submerged into a chlorine-containing liquid and loaded by axial tension is numerically modeled.

Keywords: solid-body finite elements, shells, discretization schemes.