Strength and stability analysis of UUV's cylindrical shell stiffened by inside and outside rings

With the limitation of maximum diameter 534 mm, in order to compare the qualities of shells stiffened by inside rings and outside ones, strength and stability of the shells stiffened by inside and outside rings were analyzed and radial displacement, stress and instability critical pressure were gotten using two kinds of methods, simplified mathematical models and numerical simulation adopting the software of Ansys. On the basis of this, the impact of shell diameter on strength and stability was calculated and the qualities of the shells stiffened by inside and outside rings were analyzed without the effect of diameter. The results show that the strength and stability quality of the shell stiffened by outside rings is better than the inside ones and the shell stiffened by inside rings has a stronger stress concentration. However, when the effect of maximum diameter limitation is removed, the difference of quality between the outside and inside ring-stiffened shells is very small.