Benchmark Experiment on Slab Nb with D-T Neutron for Validation of Evaluated Nuclear Data
In the fusion reactor, the first wall, blankets and superconducting magnets are directly exposed to 14.5 MeV neutrons produced by fusion reaction. Some of the characteristics of Nb metal such as high melting point, good thermal conductivity and low neutron capture cross section make Nb often used in...
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| Format: | Article |
| Language: | English |
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Editorial Board of Atomic Energy Science and Technology
2022-05-01
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| Series: | Yuanzineng kexue jishu |
| Subjects: | |
| Online Access: | https://www.aest.org.cn/CN/abstract/abstract21399.shtml |
| _version_ | 1797987176769650688 |
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| author | ZHAO Qi;NIE Yangbo;DING Yanyan;REN Jie;RUAN Xichao;HU Zhijie;XU Kuozhi |
| author_facet | ZHAO Qi;NIE Yangbo;DING Yanyan;REN Jie;RUAN Xichao;HU Zhijie;XU Kuozhi |
| author_sort | ZHAO Qi;NIE Yangbo;DING Yanyan;REN Jie;RUAN Xichao;HU Zhijie;XU Kuozhi |
| collection | DOAJ |
| description | In the fusion reactor, the first wall, blankets and superconducting magnets are directly exposed to 14.5 MeV neutrons produced by fusion reaction. Some of the characteristics of Nb metal such as high melting point, good thermal conductivity and low neutron capture cross section make Nb often used in these parts of reactor. Therefore, the quality of the evaluated nuclear data of Nb is required more accurate to ensure the safety and economy in the process of the fusion reactor working. Benchmark experiments are an important way to test and evaluate the reliability of data. A benchmark experiment on Nb was carried out with 145 MeV DT neutron source in China Institute of Atomic Energy. Slab Nb with thickness of 5 cm, 10 cm and 15 cm was selected as samples. For each thickness of Nb, the leakage neutrons from 08 MeV to 16 MeV were measured using the timeofflight method in the 60° and 120° directions. The Monte Carlo neutron transport code MCNP4C was used to simulate the leakage neutron spectra under the same experimental conditions, the Nb data was retrieved from CENDL-3.1, ENDF/B-Ⅷ.0 and JENDL-4.0 evaluation data libraries. The whole time of flight spectrum was divided into the parts contributed by four reaction channels including (n, el), (n, inl)D, (n, inl)C, and (n, 2n). The simulation integral value of each part was compared with the experimental integral value, and the C/E was obtained as the standard to verify the reliability and accuracy of the relevant data. As the results of the benchmark experiment on Nb, it can be found that: Except a little overpredict at the simulation result of elastic scattering at 120°, the Nb nuclear data of the JENDL40 data library is in good agreement with experiment results. One of the problems of CENDL31 library are that it gives too large discrete inelastic scattering cross section. The other problem may be that the secondary neutron energy spectrum given by continuous level of inelastic scattering and (n, 2n) reaction is soft. The simulation results of the ENDF/B-Ⅷ.0 data library make a huge difference. It can be seen from the comparison results that the cross section of the energy spectrum in the discrete inelastic scattering part is high and the energy spectrum given in the continuum inelastic scattering part is also problematic. The discrepancies of elastic scattering peak between 60° and 120° are considered as caused by the wrong angular distribution, especially the underestimate at 60°. So the ENDF/BⅧ.0 library has a lot to improve. In a conclusion, these three libraries are all need to be improved to get more accurate data. |
| first_indexed | 2024-04-11T07:44:50Z |
| format | Article |
| id | doaj.art-273842fccaa94af1a0b4ff573b293db9 |
| institution | Directory Open Access Journal |
| issn | 1000-6931 |
| language | English |
| last_indexed | 2024-04-11T07:44:50Z |
| publishDate | 2022-05-01 |
| publisher | Editorial Board of Atomic Energy Science and Technology |
| record_format | Article |
| series | Yuanzineng kexue jishu |
| spelling | doaj.art-273842fccaa94af1a0b4ff573b293db92022-12-22T04:36:21ZengEditorial Board of Atomic Energy Science and TechnologyYuanzineng kexue jishu1000-69312022-05-01565849859Benchmark Experiment on Slab Nb with D-T Neutron for Validation of Evaluated Nuclear DataZHAO Qi;NIE Yangbo;DING Yanyan;REN Jie;RUAN Xichao;HU Zhijie;XU Kuozhi 0China Nuclear Data Center, Key Laboratory of Nuclear Data, China Institute of Atomic Energy, Beijing 102413, China;School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, ChinaIn the fusion reactor, the first wall, blankets and superconducting magnets are directly exposed to 14.5 MeV neutrons produced by fusion reaction. Some of the characteristics of Nb metal such as high melting point, good thermal conductivity and low neutron capture cross section make Nb often used in these parts of reactor. Therefore, the quality of the evaluated nuclear data of Nb is required more accurate to ensure the safety and economy in the process of the fusion reactor working. Benchmark experiments are an important way to test and evaluate the reliability of data. A benchmark experiment on Nb was carried out with 145 MeV DT neutron source in China Institute of Atomic Energy. Slab Nb with thickness of 5 cm, 10 cm and 15 cm was selected as samples. For each thickness of Nb, the leakage neutrons from 08 MeV to 16 MeV were measured using the timeofflight method in the 60° and 120° directions. The Monte Carlo neutron transport code MCNP4C was used to simulate the leakage neutron spectra under the same experimental conditions, the Nb data was retrieved from CENDL-3.1, ENDF/B-Ⅷ.0 and JENDL-4.0 evaluation data libraries. The whole time of flight spectrum was divided into the parts contributed by four reaction channels including (n, el), (n, inl)D, (n, inl)C, and (n, 2n). The simulation integral value of each part was compared with the experimental integral value, and the C/E was obtained as the standard to verify the reliability and accuracy of the relevant data. As the results of the benchmark experiment on Nb, it can be found that: Except a little overpredict at the simulation result of elastic scattering at 120°, the Nb nuclear data of the JENDL40 data library is in good agreement with experiment results. One of the problems of CENDL31 library are that it gives too large discrete inelastic scattering cross section. The other problem may be that the secondary neutron energy spectrum given by continuous level of inelastic scattering and (n, 2n) reaction is soft. The simulation results of the ENDF/B-Ⅷ.0 data library make a huge difference. It can be seen from the comparison results that the cross section of the energy spectrum in the discrete inelastic scattering part is high and the energy spectrum given in the continuum inelastic scattering part is also problematic. The discrepancies of elastic scattering peak between 60° and 120° are considered as caused by the wrong angular distribution, especially the underestimate at 60°. So the ENDF/BⅧ.0 library has a lot to improve. In a conclusion, these three libraries are all need to be improved to get more accurate data.https://www.aest.org.cn/CN/abstract/abstract21399.shtmld-t neutron sourcetime-of-flight methodnbmcnp-4ccendl-3.1 |
| spellingShingle | ZHAO Qi;NIE Yangbo;DING Yanyan;REN Jie;RUAN Xichao;HU Zhijie;XU Kuozhi Benchmark Experiment on Slab Nb with D-T Neutron for Validation of Evaluated Nuclear Data Yuanzineng kexue jishu d-t neutron source time-of-flight method nb mcnp-4c cendl-3.1 |
| title | Benchmark Experiment on Slab Nb with D-T Neutron for Validation of Evaluated Nuclear Data |
| title_full | Benchmark Experiment on Slab Nb with D-T Neutron for Validation of Evaluated Nuclear Data |
| title_fullStr | Benchmark Experiment on Slab Nb with D-T Neutron for Validation of Evaluated Nuclear Data |
| title_full_unstemmed | Benchmark Experiment on Slab Nb with D-T Neutron for Validation of Evaluated Nuclear Data |
| title_short | Benchmark Experiment on Slab Nb with D-T Neutron for Validation of Evaluated Nuclear Data |
| title_sort | benchmark experiment on slab nb with d t neutron for validation of evaluated nuclear data |
| topic | d-t neutron source time-of-flight method nb mcnp-4c cendl-3.1 |
| url | https://www.aest.org.cn/CN/abstract/abstract21399.shtml |
| work_keys_str_mv | AT zhaoqinieyangbodingyanyanrenjieruanxichaohuzhijiexukuozhi benchmarkexperimentonslabnbwithdtneutronforvalidationofevaluatednucleardata |