The coating layers of Tri-structural Isotropic Particles(TRISO)serve to protect the kernel and act as barriers to fission products.Sintering aids in the silicon carbide matrix variably react with TRISO coating layers,...The coating layers of Tri-structural Isotropic Particles(TRISO)serve to protect the kernel and act as barriers to fission products.Sintering aids in the silicon carbide matrix variably react with TRISO coating layers,leading to the destruction of the coating layers.Investigating how carbon content affects element diffusion in silicon carbide-based TRISO composite fuel is of great significance for predicting reactor safety.In this study,silicon carbide-based TRISO composite fuels with different carbon contents were prepared by adding varying amounts of phenolic resin to the silicon carbide matrix.X-ray Diffraction(XRD)and Scanning Electron Microscopy(SEM)were employed to characterize the phase composition,morphology,and microstructure of the composite fuels.The elemental content in each coating layer of TRISO was quantified using Energy-Dispersive X-ray Spectroscopy(EDS).The results demonstrated that the addition of phenolic resin promoted the uniform distribution of sintering aids in the silicon carbide matrix.The atomic percentage(at.%)of aluminum(Al)in the pyrolytic carbon layer of the TRISO particles reached its lowest value of 0.55%when the phenolic resin addition was 1%.This is because the addition of phenolic resin caused the Al and silicon(Si)in the matrix to preferentially react with the carbon in the phenolic resin to form a metastable liquid phase,rather than preferentially consuming the pyrolytic carbon in the outer coating layer of the TRISO particles.The findings suggest that carbon addition through phenolic resin incorporation can effectively mitigate the deleterious reactions between the TRISO coating layers and sintering aids,thereby enhancing the durability and safety of silicon carbide-based TRISO composite fuels.展开更多
Objective:As a high computation cost discipline,nuclear science and engineering still relies heavily on traditional high performance computing(HPC)clusters.However,the usage of traditional HPC for nuclear science and ...Objective:As a high computation cost discipline,nuclear science and engineering still relies heavily on traditional high performance computing(HPC)clusters.However,the usage of traditional HPC for nuclear science and engineering has been limited due to the poor flexibility,the software compatibility and the poor user interfaces.Virtualized/virtual HPC(vHPC)can mimic an HPC by using a cloud computing platform.In this work,we designed and developed a vHPC system for employment in nuclear engineering.Methods:The system is tested using the computation of the numberπby Monte Carlo and an X-ray digital imaging system simulation.The performance of the vHPC system is compared with that of the traditional HPCs.Results:As the number of the simulated particles increases,the virtual cluster computing time grows propor-tionally.The time used for the simulation of the X-ray imaging was about 21.1 h over a 12 kernels virtual server.Experimental results show that the performance of virtual cluster computing and the actual physical machine is almost the same.Conclusions:From these tests,it is concluded that vHPC is a good alternative for employing in nuclear engineering.The proposed vHPC in this paper will make HPC flexible and easy to deploy.展开更多
基金funded by the Shanghai Academic/Technology Research Leader(Project No.21XD1432000).
文摘The coating layers of Tri-structural Isotropic Particles(TRISO)serve to protect the kernel and act as barriers to fission products.Sintering aids in the silicon carbide matrix variably react with TRISO coating layers,leading to the destruction of the coating layers.Investigating how carbon content affects element diffusion in silicon carbide-based TRISO composite fuel is of great significance for predicting reactor safety.In this study,silicon carbide-based TRISO composite fuels with different carbon contents were prepared by adding varying amounts of phenolic resin to the silicon carbide matrix.X-ray Diffraction(XRD)and Scanning Electron Microscopy(SEM)were employed to characterize the phase composition,morphology,and microstructure of the composite fuels.The elemental content in each coating layer of TRISO was quantified using Energy-Dispersive X-ray Spectroscopy(EDS).The results demonstrated that the addition of phenolic resin promoted the uniform distribution of sintering aids in the silicon carbide matrix.The atomic percentage(at.%)of aluminum(Al)in the pyrolytic carbon layer of the TRISO particles reached its lowest value of 0.55%when the phenolic resin addition was 1%.This is because the addition of phenolic resin caused the Al and silicon(Si)in the matrix to preferentially react with the carbon in the phenolic resin to form a metastable liquid phase,rather than preferentially consuming the pyrolytic carbon in the outer coating layer of the TRISO particles.The findings suggest that carbon addition through phenolic resin incorporation can effectively mitigate the deleterious reactions between the TRISO coating layers and sintering aids,thereby enhancing the durability and safety of silicon carbide-based TRISO composite fuels.
基金supported by National Key Research and Development Program 2016YFC0105406National Natural Science Foundation of China(11575095,61571262)。
文摘Objective:As a high computation cost discipline,nuclear science and engineering still relies heavily on traditional high performance computing(HPC)clusters.However,the usage of traditional HPC for nuclear science and engineering has been limited due to the poor flexibility,the software compatibility and the poor user interfaces.Virtualized/virtual HPC(vHPC)can mimic an HPC by using a cloud computing platform.In this work,we designed and developed a vHPC system for employment in nuclear engineering.Methods:The system is tested using the computation of the numberπby Monte Carlo and an X-ray digital imaging system simulation.The performance of the vHPC system is compared with that of the traditional HPCs.Results:As the number of the simulated particles increases,the virtual cluster computing time grows propor-tionally.The time used for the simulation of the X-ray imaging was about 21.1 h over a 12 kernels virtual server.Experimental results show that the performance of virtual cluster computing and the actual physical machine is almost the same.Conclusions:From these tests,it is concluded that vHPC is a good alternative for employing in nuclear engineering.The proposed vHPC in this paper will make HPC flexible and easy to deploy.