Reconstruction of experimental axisymmetric equilibria is an important part of tokamak data analysis. Fourier expansion is applied to reconstruct the vessel current distribution in EFIT code. Benchmarking and testing ...Reconstruction of experimental axisymmetric equilibria is an important part of tokamak data analysis. Fourier expansion is applied to reconstruct the vessel current distribution in EFIT code. Benchmarking and testing calculations are performed to evaluate and validate this algorithm. Two cases for circular and non-circular plasma discharges are presented. Fourier expansion used to fit the eddy current is a robust method and the real time EFIT can be introduced to the plasma control system in the coming campaign.展开更多
The welding coarse-grained heat-affected zones（CGHAZs） in the undoped and Ce-doped samples of SA508CL-3 reactor pressure vessel steel were simulated using a Gleeble 1500 D thermomechanical simulator with a peak temp...The welding coarse-grained heat-affected zones（CGHAZs） in the undoped and Ce-doped samples of SA508CL-3 reactor pressure vessel steel were simulated using a Gleeble 1500 D thermomechanical simulator with a peak temperature of 1320 oC at the heat inputs of 30, 50 and 100 kJ /cm, respectively. The ductile-to-brittle transition temperature（DBTT） of the simulated CGHAZs was evaluated along with microstructural and microchemical characterizations. The results indicated that Ce could substantially lower the DBTT of the CGHAZs by its microstructural and microchemical effects. After the thermal cycling of welding, the microstructure in the Ce-doped samples was apparently finer than that in the undoped samples, regardless of the lath bainite obtained at the heat inputs of 30 and 50 kJ /cm or the granular bainite acquired at the heat input of 100 kJ /cm, leading to lower DBTTs for the Ce-doped samples. Moreover, grain boundary segregation of Ce occurred apparently in the Ce-doped samples and exhibited a non-equilibrium characteristic. The segregation of Ce could play an important role in lowering the DBTT of CGHAZs or toughening the CGHAZs.展开更多
基金supported by National Natural Science Foundation of China (No. 10725523)
文摘Reconstruction of experimental axisymmetric equilibria is an important part of tokamak data analysis. Fourier expansion is applied to reconstruct the vessel current distribution in EFIT code. Benchmarking and testing calculations are performed to evaluate and validate this algorithm. Two cases for circular and non-circular plasma discharges are presented. Fourier expansion used to fit the eddy current is a robust method and the real time EFIT can be introduced to the plasma control system in the coming campaign.
基金supported by the National Natural Science Foundation of China(51071060)
文摘The welding coarse-grained heat-affected zones（CGHAZs） in the undoped and Ce-doped samples of SA508CL-3 reactor pressure vessel steel were simulated using a Gleeble 1500 D thermomechanical simulator with a peak temperature of 1320 oC at the heat inputs of 30, 50 and 100 kJ /cm, respectively. The ductile-to-brittle transition temperature（DBTT） of the simulated CGHAZs was evaluated along with microstructural and microchemical characterizations. The results indicated that Ce could substantially lower the DBTT of the CGHAZs by its microstructural and microchemical effects. After the thermal cycling of welding, the microstructure in the Ce-doped samples was apparently finer than that in the undoped samples, regardless of the lath bainite obtained at the heat inputs of 30 and 50 kJ /cm or the granular bainite acquired at the heat input of 100 kJ /cm, leading to lower DBTTs for the Ce-doped samples. Moreover, grain boundary segregation of Ce occurred apparently in the Ce-doped samples and exhibited a non-equilibrium characteristic. The segregation of Ce could play an important role in lowering the DBTT of CGHAZs or toughening the CGHAZs.
