PSI - Issue 47

Sergei Kabrits et al. / Procedia Structural Integrity 47 (2023) 513–520 S. Kabrits and E. Kolpak / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 4. The shape of a quarter of the shell (left) and the relative stresses along the shell meridian at time t 2 (right).

Fig. 5 The maximum relative stresses (left) and the thickness (right) at the initial ( t=0 ) and final ( t 2 ) time along the meridian.

It is clear that the lifetime of the shell should be dependent on the radius of the toroidal element. Figure 6 shows the dependence of the shell lifetime on the radius of the torus which provides a smooth transition from the spherical part of the shell to the cylindrical. Zero value of the torus radius means that the angle of rotation during the transition from the sphere to the cylinder suffers a discontinuity of the 1st kind. In this case, maximum stresses are observed and, accordingly, the minimum service life of the structure. The maximum service life is observed when the radius of the cylinder coincides with the radius of the sphere.