V.N. Zaytsev, M.I. Martirosov, L.N. Rabinsky, E.V. Serpicheva

Stress-strain condition of cylinder under internal pressure is investigated, also submitted selection of optimal design. The cylinder is designed as cylindrical middle part and two spherical bottoms. it is made of composite such as carbon fiber containing sealed metal layer. As the sealed layer were used aluminum, steel and titan alloys. Analytical solution for this is not available, that is why we used numerical method - finite elements method. We used multilayer torque finite element. For the cylinder with aluminum sealed layer was made a selection for the number of layers providing desire strength. For metal and composite layers were used different criteria. The nonlinear graph ,was made to determine the limiting stresses, because strain of the sealed layer exceed the yield strength. Discovered 3 different versions of cylinder with equal number of composite layers and sealed layers with different alloys. For even cylinder was found margin of safety on the most loaded composite layer and maximum equivalent tension in sealed layer. All the cylinders satisfy strength conditions, but have different weight. The most optimal is cylinder with aluminum sealed layer.