Analysis of the interactions between spent fuel pebble bed and storage canister under impact loading
The high temperature gas-cooled reactor pebble-bed modular (HTR-PM) stores spent fuel on-site by a dry storage system based on canisters. To ensure the safety containment of the radioactive contents, it is necessary to assess the interactions between spent fuel pebble bed and storage canister under impact loading, such as the event of accidental drop. In this paper, the thin walled canister and the pebble bed inside are modelled by finite element method (FEM) and discrete element method (DEM), respectively. With coupling the two types of model, the dynamic structural interactions inside the pebble bed and between the spent fuel elements and the wall of canisters under impact loading are analyzed numerically. The results show that this method can effectively evaluate the safety and structural design rationality of the fuel storage canister and provide a reference for the subsequent design of fuel canisters.
Keywords: HTR-PM, Spent fuel, Impact, Safety analysis