Simulation study on the characteristics of driving line rod drop based on passive acceleration

[Background] Under the condition of tilting and swinging marine environment, the driving line of modular floating reactor (MFR) faces with a worse dropping rod environment than that under the condition of vertical fixation. [Purpose] This study aims to explore the characteristics of driving line rod drop based on passive acceleration for MFR. [Methods] First of all, a spring was added to the driving line to realize the passive acceleration rod drop. Then, the simulation study of the drop behavior of the driving line rod of MFR was carried out on the base of the existing one dimensional hydraulic simulation model of drive line rod drop and considering the influence of the spring transient force. Culation software 'MATLAB' and dynamics simulation software 'Motion' were combined to obtain variation curves of displacement, velocity and hydraulic force in the process of control rod dropping. [Results and Conclusions] Simulation results show that the spring has certain improvement effect on the control rod drop time, which helps to overcome the resistance when the control rod drops in the state of sloping and swing. (authors)