Numerical investigation on the fluid added mass of spent fuel storage rack

Spent fuel storage rack is the most important equipment for storing spent fuel after refueling in nuclear power station. Free standing storage rack has an advantage to protect the structural integrity of the rack, because the fluid-structure interaction of the free standing rack can dissipate the earthquake energy and reduce the movement of rack, when earthquake occurs. The fluid added mass is a main parameter for studying the fluid-structure interaction effect, which provides an important parameter for the transient structural analysis of the storage rack. However, the calculation methods of fluid added mass, which in engineering, are only for the simple geometric structure such as circular cylinder or square cylinder. It cannot apply to the spent fuel storage rack, which the geometric structure is extraordinarily complex. In this paper, in order to investigate a more accurate fluid added mass, a 2-dimensional dynamic model was constructed. Furthermore, the transient analysis of the 2-dimensional model was conducted by Computational Fluid Dynamics (CFD) software, Fluent. Then, the added mass of the model was obtained according to CFD transient fluid force. Moreover, a model which corresponding to the previous vibration experiment of rack was conducted to verifies the correctness of the model. From numerical results, some important features for the design of rack were found. This study can offer the assistance for the design and manufacture of spent fuel pools and high-density spent fuel storage racks, ultimately.