Probabilistic safety assessment(PSA) is important in nuclear safety review and analysis. Because the design and physics of the fluoride salt-cooled high temperature reactor(FHR) differ greatly from the pressurized wat...Probabilistic safety assessment(PSA) is important in nuclear safety review and analysis. Because the design and physics of the fluoride salt-cooled high temperature reactor(FHR) differ greatly from the pressurized water reactor(PWR), the methods and steps of PSA in FHR should be studied. The high-temperature gascooled reactor(HTR-PM) and sodium-cooled fast reactors have built the PSA framework, and the framework to finish the PSA analysis. The FHR is compared with the PWR, HTR-PM and sodium-cooled fast reactors from the physics, design and safety. The PSA framework of FHR is discussed. In the FHR, the fuel and coolant combination provides large thermal margins to fuel damage(hundreds of degrees centigrade). The tristructuralisotropic(TRISO) as the fuel is independent in FHR core and its failure is limited for the core. The core damage in Level 1 PSA is of lower frequency. Levels 1 and 2 PSA are combined in the FHR PSA analysis. The initiating events analysis is the beginning, and the source term analysis and the release types are the target. Finally, Level3 PSA is done.展开更多
Success criteria analysis(SCA) bridges the gap between deterministic and probabilistic approaches for risk assessment of complex systems. To develop a risk model,SCA evaluates systems behaviour in response to postulat...Success criteria analysis(SCA) bridges the gap between deterministic and probabilistic approaches for risk assessment of complex systems. To develop a risk model,SCA evaluates systems behaviour in response to postulated accidents using deterministic approach to provide required information for the probabilistic model. A systematic framework is proposed in this article for extracting the front line systems success criteria. In this regard, available approaches are critically reviewed and technical challenges are discussed. Application of the proposed methodology is demonstrated on a typical Westinghouse-type nuclear power plant. Steam generator tube rupture is selected as the postulated accident. The methodology is comprehensive and general; therefore, it can be implemented on the other types of plants and complex systems.展开更多
Person-borne improvised explosive devices(PBIEDs)are often used in terrorist attacks in Western countries.This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people expos...Person-borne improvised explosive devices(PBIEDs)are often used in terrorist attacks in Western countries.This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people exposed to this hazard.An explosive field test with a typical PBIED composed of a plastic explosive charge and steel nut enhancements was performed to record initial fragment behaviour,including positions,velocity,and trajectory angles.These data were used to predict the full trajectory of PBIED fragments using a probabilistic analysis.In the probabilistic analyses a probability of fatality or serious injury was computed.Based on the results presented,many practical conclusions can be drawn,for instance,regarding safe evacuation distances if a person were exposed to a suspected PBIED.展开更多
基金Supported by Chinese Academy of Science Strategy Precursor Science and Technology Project(No.XDA0205050)
文摘Probabilistic safety assessment(PSA) is important in nuclear safety review and analysis. Because the design and physics of the fluoride salt-cooled high temperature reactor(FHR) differ greatly from the pressurized water reactor(PWR), the methods and steps of PSA in FHR should be studied. The high-temperature gascooled reactor(HTR-PM) and sodium-cooled fast reactors have built the PSA framework, and the framework to finish the PSA analysis. The FHR is compared with the PWR, HTR-PM and sodium-cooled fast reactors from the physics, design and safety. The PSA framework of FHR is discussed. In the FHR, the fuel and coolant combination provides large thermal margins to fuel damage(hundreds of degrees centigrade). The tristructuralisotropic(TRISO) as the fuel is independent in FHR core and its failure is limited for the core. The core damage in Level 1 PSA is of lower frequency. Levels 1 and 2 PSA are combined in the FHR PSA analysis. The initiating events analysis is the beginning, and the source term analysis and the release types are the target. Finally, Level3 PSA is done.
文摘Success criteria analysis(SCA) bridges the gap between deterministic and probabilistic approaches for risk assessment of complex systems. To develop a risk model,SCA evaluates systems behaviour in response to postulated accidents using deterministic approach to provide required information for the probabilistic model. A systematic framework is proposed in this article for extracting the front line systems success criteria. In this regard, available approaches are critically reviewed and technical challenges are discussed. Application of the proposed methodology is demonstrated on a typical Westinghouse-type nuclear power plant. Steam generator tube rupture is selected as the postulated accident. The methodology is comprehensive and general; therefore, it can be implemented on the other types of plants and complex systems.
基金This work was supported by the Poland National Center for Research and Development,under the grant DOB-BIO10/01/02/2019 within the Defence and Security Programme.
文摘Person-borne improvised explosive devices(PBIEDs)are often used in terrorist attacks in Western countries.This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people exposed to this hazard.An explosive field test with a typical PBIED composed of a plastic explosive charge and steel nut enhancements was performed to record initial fragment behaviour,including positions,velocity,and trajectory angles.These data were used to predict the full trajectory of PBIED fragments using a probabilistic analysis.In the probabilistic analyses a probability of fatality or serious injury was computed.Based on the results presented,many practical conclusions can be drawn,for instance,regarding safe evacuation distances if a person were exposed to a suspected PBIED.
