The effect of welding residual stress on the free vibration of underwater cylindrical shell

The effect of welding residual stress on the vibration of underwater cylindrical shell is investigated. The welding residual stress of practical underwater structure, such as submarine, is widespread and complicate distributed. However, the earlier theoretical studies which mainly focused on the overall uniform distributed stress cannot be applied to deal with this practical vibration problem. In this paper, we offer a new theoretical analysis method aim at non-uniform distributed welding distributed stress. Based on the Flugge theory, considering the Fluid Structure Interaction (FSI), we derive the motion equations of the underwater cylindrical shell with welding residual stress. By means of a polynomial approximation and quadratic matrix linearization, we solve the nonlinear eigenvalue problem caused by the welding residual stress and FSI. Some numerical examples are used to validate our method and compare the welding residual stress-caused influence in the air and water.