Author Affiliations
1School of National Defense Science and Technology, Southwest University of Science and Technology, Mianyang 621010, China2Center for Advanced Material Diagnostic Technology, Shenzhen Technology University, Shenzhen 518118, Chinashow less
Fig. 1. Nuclear reaction chain of thermal neutron in 6LiD
Fig. 2. Schematic diagram of transmutation rods (a) Radial structure of transmutation rod, (b) Axial uniform transmutation rod, (c) Axial three-segment transmutation rod, (d) Axial five-segment transmutation rod, (e) Axial seven-segment transmutation rod
Fig. 3. Position distribution of transmutation rods in fuel assembly (color online)
Fig. 4. Effect on keff under different 6LiD/MA ratio in transmutation clading material
Fig. 5. The effect on neutron spectrum while transmutation mass ratio of 6LiD to MA is 2∶8 and thickness is 2 mm
Fig. 6. Effect on transmutation rate of mass ratio of 6LiD to MA in transmutation material
Fig. 7. Variation of MA transmutation rate within 540 d with different axial structure of transmutation rods
Fig. 8. Axial neutron flux distribution in core when axial structure of transmutation rods is different
堆芯参数 Core parameter | 设计值 Data used in simulation |
|---|
| 堆芯活性段Active core height / mm | 3 657.6 | 堆芯等效直径 Equivalent diameter / mm | 3 228 | 燃料富集度/组件数UO2 Enrichment and assemblies number | 177 (2.4%/61+3.1%/68+4.4%/48) | | 燃料密度Density of UO2 / g·cm-3 | 10.41 | 燃料棒排列方式 Fuel assembly pattern | 17×17 | | 包壳材料Cladding material | Zr合金 Zircaloy | | 包壳厚度Cladding thickness / mm | 0.57 | | 包壳外径Cladding out radius / mm | 9.5 | 燃料棒间距 Space between fuel rods / mm | 13 | UO2芯块直径 UO2 fuel diameter / mm | 8.192 |
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Table 1. Parameters of PWR core
| 核素Isotopes | 237Np | 241Am | 243Am | 244Cm |
|---|
| 比例Nuclide ratio / % | 56.2 | 26.4 | 12 | 5.4 |
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Table 2. Composition and molar fraction of MA
| 核素Isotopes | 热谱Thermal | 快谱Fast |
|---|
| 237Np | 63 | 5.3 | | 241Am | 100 | 7.4 | | 243Am | 111 | 8.6 | | 244Cm | 16 | 1.4 |
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Table 3. Capture-to-fission ratio for main nuclides of core fuel
| 参数Parameters | 设计值 Data used in simulation |
|---|
| 包壳材料Cladding material | 锆合金 Zircaloy | | 包壳厚度Cladding thickness / mm | 0.57 | | 包壳外径Cladding out radius / mm | 9.5 | | 轴向均匀嬗变棒MA涂层厚度MA coating thickness of axial-uniform transmutation rods / mm | 2 | | 轴向三段式嬗变棒MA涂层厚度MA coating thickness of axial-three-segment transmutation rods / mm | 2, 3, 2 | | 轴向五段式嬗变棒MA涂层厚度MA coating thickness of axial-five-segment transmutation rods / mm | 1, 2, 3, 2, 1 | | 轴向七段式嬗变棒MA涂层厚度MA coating thickness of axial-seven-segment transmutation rods / mm | 0.5, 1, 2, 3, 2, 1, 0.5 | | 嬗变棒高度Heigh of transmutation rods / mm | 3 657.6 |
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Table 4. Parameters of MA transmutation rod
| 核素Isotopes | 涂层厚度Clading thickness / mm |
|---|
| 0.1 | 0.5 | 1.0 | 1.5 | 2.0 |
|---|
| 237Np嬗变率237Np Transmutation rate / % | 25.82 | 21.83 | 21.04 | 20.59 | 20.38 | | 241Am嬗变率241Am Transmutation rate / % | 60.16 | 45.98 | 42.22 | 40.09 | 38.99 | | 243Am嬗变率243Am Transmutation rate / % | 25.96 | 21.86 | 21.80 | 21.80 | 21.94 | | 244Cm嬗变率244Cm Transmutation rate / % | -45.33 | -36.56 | -34.54 | -33.55 | -33.02 | | MA嬗变率MA transmutation rate / % | 31.22 | 25.56 | 24.31 | 23.59 | 23.25 | | MA裂变率MA fission rate / % | 3.67 | 3.83 | 3.88 | 3.92 | 3.94 | | MA嬗变量MA transmutation amount / kg | 46.3 | 180.3 | 320.7 | 434.5 | 528.1 |
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Table 5. Transmutation condition based on different transmutation coating thickness after 540-day-explosure (6LiD∶MA=2∶8)
嬗变棒设计方案 Transmutation rods design scheme | 单根嬗变棒中 MA的质量 MA mass of one transmutation rod / kg | MA总装载 质量 MA mass loaded in total / kg | MA总 嬗变率 MA transmutation rate in total / % | MA总 嬗变量 MA transmutation mass in total / % | MA总 裂变率 MA fission rate in total / % | 等效MA年产 量•每堆 （PWR） Equivalence to the annual MA yield of a PWR |
|---|
轴向均匀嬗变棒 Axial uniform transmutation rods | 1.724 | 2 648.67 | 23.25 | 548.26 | 3.94 | 21.79 | 轴向三段式嬗变棒 Axial three-segment transmutation rods | 1.489 | 2 287.27 | 24.05 | 491.76 | 4.48 | 19.54 | 轴向五段式嬗变棒 Axial five-segment transmutation rods | 1.046 | 1 607.21 | 24.44 | 351.84 | 4.46 | 13.98 | 轴向七段式嬗变棒 Axial seven-segment transmutation rods | 0.856 | 1 314.15 | 25.43 | 300.81 | 4.43 | 11.95 |
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Table 6. Transmutation rate, fission rate and transmutation amount after 540-d-explosure
| 嬗变棒结构Transmutation rod structure | 轴向功率峰因子Axial power peak factor |
|---|
| 干净堆芯Clean core | 1.778 | | 轴向均匀嬗变棒Axial-uniform transmutation rods | 1.737 | | 轴向三段式嬗变棒Axial-three-segment transmutation rods | 1.375 | | 轴向五段式嬗变棒Axial-five-segment transmutation rods | 1.408 | | 轴向七段式嬗变棒Axial-seven-segment transmutation rods | 1.546 |
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Table 7. Axial power peak factor
