Research on the Shock Resistance Optimal Design of Submerged Nuclear Power Plants Model Subjected to Underwater Explosions

The research on the linear and nonlinear responses of the plant structures, especially with internal equipment, subjected to underwater shock load make great significance in assessing the shock resistance ability of submerged nuclear power plants. In this paper, an optimal design of a small-sized submerged vehicle with internal components has been carried out to enhance the shock resistance. The dynamic responses and deformation mode of the vehicle subjected to underwater shock wave are firstly analyzed to determine the weak parts. The incident wave induced by UNDEX is equivalently replaced by half-sine shock wave, as the calculation of fluid-structure interaction (FSI) in the optimization process is very complicated. Based on the constraint condition of invariant weight, an optimization procedure is established by means of the commercial finite element code and optimization method. Numerical simulation is carried out to validate the effective of the optimal procedure. Compared with the original one, the maximum Mises stress of the submerged vehicle decreased from 426MPa to 359MPa, approximately reducing by 15.73%. The optimal result can be used to redesign the submerged vehicle with internal components suffered from underwater shock loading, as well as to enhance the anti-shock capability of submerged nuclear power plants.