Sealing Performance Analysis Of Main Vessel Of Liquid Metal Cooled Reactor

Liquid metal cooled reactor is one type of Generator IV reactor, which is most promising in the future due to the high performance in security features, neutronics, and thermal hydraulics. Different from the pressurized water reactor, liquid metal cooled reactor use liquid metal as the coolant and in which primary loop is pool type, low operation pressure of cover gas is important feature of inherent safety of liquid metal cooled reactor. Pressure in main vessel is negative state in normal operation condition while it will turn to positive state in design basic accident, hence a bidirectional gas sealing is demanded by main vessel to meet the requirement of varying pressure state.Based on the dual-pressure feature of cover gas of liquid metal cooled reactor, a bidirectional sealing scheme is proposed by setting two metallic sealing rings. Taking a typical vessel of liquid metal cooled rector for example, mechanical performance is analyzed by ANSYS APDL simulation environment which is based on the finite-element method. The gas leakage rate under the environment of normal operation and basic design accident are analyzed by the equipment of sealing gas leakage rate calculation. On this basis, sealing performance under circumstance of single ring failure and under different metallic coverage are analyzed.The result suggests that gas sealing of main vessel of liquid metal cooled reactor is always maintain in good performance under normal operation condition and basic design accident, sealing rings are in the elastic range. Under different condition, gas leakage rate both are in the limit of standard. It is demonstrated that the bidirectional gas sealing of main vessel has good sealing performance. Only single sealing ring can also keep good gas sealing shows that dual sealing rings of liquid metal cooled play a role of redundancy. Sealing rings with on metal coverage can not keep a good performance of gas sealing, it indicate that any part of sealing rings is vital. Metal which is smaller rigidity is in favor of contact surface extent, leakage rate decrease obviously. It demonstrate that soft metal can reduce gas leakage more effectively.