Study On Neutronics Analysis Of Water Cooled Breeder Blanket

Blanket is one of the main systems in magnetic confinement fusion reactors.It is necessary to conduct neutronics calculations to obtain source terms for the thermal hydraulic design,nuclear safety analysis,evaluation of the tritium breeding ability,as well as the analysis of material irradiation damage and material life in blankets.Based on the design of the China Fusion Engineering Test Reactor(CFTER),this work use CAD/MC software tools to develop three-dimensional neutronics models to study the neutronics characteristics of the water cooled ceramic breeder(WCCB)blanket and the water cooled lithium lead(WCLL)blanket originally proposed for the EU-DEMO,as well as the low-activation feature of a kind of structural steel.Using the Monte Carlo N-Particle Transport code(MCNP)and the activation code FISPACT,neutronics analysis has been performed,and the results are expected to provide useful insights for the blanket optimization and selection of structural materials.First,based on the CFETR-2018 and updated WCCB blanket's design,a detailed 3D neutronics model was developed.MCNP was used to study the tritium breeding ratio(TBR),nuclear heat deposition and material irradiation of the WCCB blanket under different fusion powers.The results show that the TBR can meet the requirement of CFETR under fusion power from 200MW to 1.5GW,even in consideration of windows for other influence factors(TBR)1.1).The nuclear heating power of the WCCB blanket under 1.5GW reaches 1410.78MW.The energy multiplication factor is 1.175.The displacement per atom of the plasma-facing component and first wall reach 6.767 and 10.335 per full power year(FPY).The shielding performance of the WCCB blanket was preliminarily evaluated by one dimensional neutronics model.The result indicates that the WCCB blanket can meet the shielding requirement.Second,based on the Multi Module Segment(MMS)design of WCLL blanket,the WCLL neutronics model was developed and intergrated into the CFETR neutronics model.The neutronics analysis was carried out.The result shows that the TBR is 1.19,with outboard blankets contributing 74.47%and inboard blankets contributing 25.53%.The WCLL blanket can provides enough shielding capability for TF coils.Using the same CFETR model,the neutronics performances of CFETR-WCCB and EU-WCLL blankets are compared.Besides,based on the neutronics model for the CFETR-WCCB blanket,the potential application of the new Martensitic heat-resistant steel SIMP in the fusion reactor environment is studied.The activation performance was evaluated by the coupling calculation of the specific activity,decay heat,contact dose rate,clear index and radiation damage,using MCNP and FISPACT.The result concludes that SIMP has good activation performance.From the viewpoint of low material activation,it can be chosen as one candidate structural material used for fusion devices.