Seismic Performance Analysis Of Main Vessel Of Lead-bismuth Alloy Cooled Reactor

As the very promising advanced reactor type of new generation of nuclear power systems, lead-bismuth alloy cooled reactor has become a hot research at home and abroad with high performance in neutronics, chemistries, thermal hydraulics and security features. At2011, Chinese Academy of Sciences (CAS) started the "Strategic Priority Research Program" named "Future Advanced Nuclear Fission Energy-Accelerator Driven Sub-critical System", which chooses CLEAR (China LEAd-based Reactor) as the candidate reactor type.Seismic performance of the reactor directly affects safety and economy. As Class I Seismic equipment according to national nuclear safety guidelines, the main vessel is the major containment to catch radioactive release, whose seismic performance has important significance on maintaining the structural integrity and ensuring the safety of reactor.Compared with the traditional reactor type, lead-bismuth alloy cooled reactor is an integrative pool-type reactor, which uses liquid lead-bismuth alloy as the primary coolant. Under earthquakes, the main vessel strains so much because of the fluid sloshing effect caused by heavy liquid metal that may cause structure damage and then loss of function of the main vessel. Therefore, it is very necessary to carry on the research of seismic performance of main vessel of lead-bismuth alloy cooled reactor.According to the ASME code, the nuclear Power Earthquake code, nuclear safety guidelines and regulation codes, seismic performance of lead-bismuth alloy cooled reactor is analyzed by transient dynamics module under ANSYS Workbench simulation environment which is based on the finite-element method. Mechanics performance, which is under RG1.60standard design response spectrum of the main vessel, is evaluated, and the stress intensity calculation with assessment of the main vessel is completed. On this basis, factors influencing seismic performance of main vessel of lead-bismuth alloy cooled reactor are analyzed. Diameter, thickness and coolant type are chosen as the representative factors and their influences on seismic performance of the main vessel are discussed.The results suggest that materials of main vessel are always in the linear elastic range under the process of seismic load without structural failure and destruction. It is demonstrated that the main vessel has good seismic performance and its design is reasonable which meets the relevant guidelines and regulation codes about seismic performance of the main vessel. And with decrease of the thickness, the increase of the diameter and the coolant density, deformation and stress intensity of the main vessel increases. The above conclusions provide a basis to liquid metal cooled reactor such as lead-bismuth alloy cooled reactor main vessel design.