REINFORCING INCLUSION EFFECT ON THE STRESS CONCENTRATION WITHIN THE SPHERICAL SHELL HAVING AN ELLIPTICAL OPENING UNDER UNIFORM INTERNAL PRESSURE

The authors present the results of computer simulation of the stress-strain state of a thin-walled spherical shell with an elliptical opening and the surrounding reinforcing inclusion of another material. The effect of geometric and mechanical parameters of inclusions on the stress distribution around the opening and deformation of the shell under uniform internal pressure are investigated. The issue of stress concentration in modern leading fields of technology and industry, namely, in mechanical engineering, rocket, and space, is quite topical since it is associated with the reliability and durability of the designed structures or their elements. Stress concentrators can occur due to imperfections in the materials’ structure (cavities, cracks, foreign inclusions, etc.) or technological and structural necessity (openings, cutouts, leaks). Shell structures are used as load-carrying structures in many fields of engineering. They combine high strength with low weight, which contributes to their reliability and safety during operation. In most cases, shells in real structures have simple geometric surfaces (shells of rotation). Complex structures are usually a combination of such shells. It is important to investigate the effect of local stress concentrators as openings (considering inclusions) on the stress-strain state of shells. The methods of stress concentration reduction should be outlined. The authors performed a finite element analysis of the effect of reinforcements modeled by inclusions made of the different materials as compared with the shell material having an opening on the parameters of its stress-strain state. Such investigations are crucial for the design and optimization of the structures in many engineering fields.