反应堆物理设计不确定度是第4代核能系统的QMU(quantification of margins and uncertainties)有效性认证所必须的参数之一,核数据不确定度是其重要来源。基于自主开发的耦合程序BUND(burnup uncertainty of nuclear data),将SCALE程序T...反应堆物理设计不确定度是第4代核能系统的QMU(quantification of margins and uncertainties)有效性认证所必须的参数之一,核数据不确定度是其重要来源。基于自主开发的耦合程序BUND(burnup uncertainty of nuclear data),将SCALE程序TRITON和TSUNAMI-3D模块耦合,完成了熔盐堆钍铀燃料循环、铀钚燃料循环核数据引起的有效增殖因数keff不确定度分析,并与ENDF/B-Ⅶ.1协方差数据库计算结果进行了对比。结果显示:初始时刻,两种燃料循环模式下,核数据导致的keff不确定度分别为0.490%和0.582%。随燃耗的增加,核数据引起的keff不确定度增加。寿期末,两种燃料循环模式下,对keff不确定度影响显著增加的反应道分别为239Pu(nubar)、(n,f)、(n,γ)、105 Rh(n,γ)、135 Xe(n,γ)和234 U(n,γ)、143 Nd(n,γ)、131,135 Xe(n,γ)等。展开更多
The molten salt reactor(MSR), as one of the Generation Ⅳ advanced nuclear systems, has attracted a worldwide interest due to its excellent performances in safety, economics, sustainability, and proliferation resistan...The molten salt reactor(MSR), as one of the Generation Ⅳ advanced nuclear systems, has attracted a worldwide interest due to its excellent performances in safety, economics, sustainability, and proliferation resistance. The aim of this work is to provide and evaluate possible solutions to fissile 233 U production and further the fuel transition to thorium fuel cycle in a thermal MSR by using plutonium partitioned from light water reactors spent fuel. By using an in-house developed tool, a breeding and burning(B&B) scenario is first introduced and analyzed from the aspects of the evolution of main nuclides, net 233 U production, spectrum shift, and temperature feedback coefficient. It can be concluded that such a Th/Pu to Th/^(233)U transition can be accomplished by employing a relatively fast fuel reprocessing with a cycle time less than 60 days. At the equilibrium state, the reactor can achieve a conversion ratio of about 0.996 for the 60-day reprocessing period(RP) case and about 1.047 for the 10-day RP case.The results also show that it is difficult to accomplish such a fuel transition with limited reprocessing(RP is 180 days),and the reactor operates as a converter and burns the plutonium with the help of thorium. Meanwhile, a prebreeding and burning(PB&B) scenario is also analyzed briefly with respect to the net 233 U production and evolution of main nuclides. One can find that it is more efficient to produce 233 U under this scenario, resulting in a double time varying from about 1.96 years for the 10-day RP case to about 6.15 years for the 180-day RP case.展开更多
文摘反应堆物理设计不确定度是第4代核能系统的QMU(quantification of margins and uncertainties)有效性认证所必须的参数之一,核数据不确定度是其重要来源。基于自主开发的耦合程序BUND(burnup uncertainty of nuclear data),将SCALE程序TRITON和TSUNAMI-3D模块耦合,完成了熔盐堆钍铀燃料循环、铀钚燃料循环核数据引起的有效增殖因数keff不确定度分析,并与ENDF/B-Ⅶ.1协方差数据库计算结果进行了对比。结果显示:初始时刻,两种燃料循环模式下,核数据导致的keff不确定度分别为0.490%和0.582%。随燃耗的增加,核数据引起的keff不确定度增加。寿期末,两种燃料循环模式下,对keff不确定度影响显著增加的反应道分别为239Pu(nubar)、(n,f)、(n,γ)、105 Rh(n,γ)、135 Xe(n,γ)和234 U(n,γ)、143 Nd(n,γ)、131,135 Xe(n,γ)等。
基金supported by the Chinese TMSR Strategic Pioneer Science and Technology Project(No.XDA02010000)the National Natural Science Foundation of China(No.91326201)the Frontier Science Key Program of the Chinese Academy of Sciences(No.QYZDY-SSW-JSC016)
文摘The molten salt reactor(MSR), as one of the Generation Ⅳ advanced nuclear systems, has attracted a worldwide interest due to its excellent performances in safety, economics, sustainability, and proliferation resistance. The aim of this work is to provide and evaluate possible solutions to fissile 233 U production and further the fuel transition to thorium fuel cycle in a thermal MSR by using plutonium partitioned from light water reactors spent fuel. By using an in-house developed tool, a breeding and burning(B&B) scenario is first introduced and analyzed from the aspects of the evolution of main nuclides, net 233 U production, spectrum shift, and temperature feedback coefficient. It can be concluded that such a Th/Pu to Th/^(233)U transition can be accomplished by employing a relatively fast fuel reprocessing with a cycle time less than 60 days. At the equilibrium state, the reactor can achieve a conversion ratio of about 0.996 for the 60-day reprocessing period(RP) case and about 1.047 for the 10-day RP case.The results also show that it is difficult to accomplish such a fuel transition with limited reprocessing(RP is 180 days),and the reactor operates as a converter and burns the plutonium with the help of thorium. Meanwhile, a prebreeding and burning(PB&B) scenario is also analyzed briefly with respect to the net 233 U production and evolution of main nuclides. One can find that it is more efficient to produce 233 U under this scenario, resulting in a double time varying from about 1.96 years for the 10-day RP case to about 6.15 years for the 180-day RP case.
