Neutronics assessment of advanced shield materials using metal hydride and borohydride for fusion reactors
Neutronics assessment of advanced shield materials using metal hydride and borohydride for fusion reactors
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DOI：
10.1016/j.fusengdes.2005.09.060
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发表时间：
2006-02
影响因子：
1.7
通讯作者：
T. Hayashi;K. Tobita;S. Nishio;K. Ikeda;Y. Nakamori;S. Orimo
中科院分区：
文献类型：
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作者：
T. Hayashi;K. Tobita;S. Nishio;K. Ikeda;Y. Nakamori;S. Orimo
对金属氢化物和硼氢化物作为先进屏蔽材料的能力进行了中子输运计算。某些氢化物的氢含量比聚乙烯和固体氢高得多。与传统材料相比，富氢氢化物具有更好的中子屏蔽能力。采用一维圆柱体模型进行中子输运计算。护盾位于内侧和外侧，径向厚度分别为30 cm和70 cm。与钢和水的组合相比，镁(BH4)2、TiH_2和ZrH_2可使外侧屏蔽层厚度分别减薄23%、20%和19%。掺入Mg(BH4)2和F82H对伽马射线有很大的屏蔽作用。在混合比为0.5时，尽管快中子通量比纯Mg(BH4)2的快中子通量大13%，但伽马射线通量却比纯Mg(BH4)2的小300倍。在Mg(BH4)2的中子谱中，由于硼的影响，能量范围小于100 eV的中子通量比其他材料的明显降低。
Neutron transport calculations have been performed to evaluate the capability of metal hydrides and borohydrides as advanced shielding materials. Some hydrides are characterized by considerably higher hydrogen content than polyethylene and solid hydrogen. The hydrogen-rich hydrides show superior neutron shielding capability compared to the conventional materials. A one-dimensional cylindrical model was used to do the neutron transport calculation. The shields are located at the inboard and outboard sides, and they are 30 and 70cm in radial thickness, respectively. Mg(BH4)2, TiH2and ZrH2can reduce the thickness of the outboard shield by 23, 20 and 19%, respectively, compared to the combination of steel and water. Mixing Mg(BH4)2with F82H produces large effects in the gamma-ray shielding. In the mixing ratio of 0.5, the gamma-ray flux was 300 times smaller than that of pure Mg(BH4)2, even though the fast neutron flux is 13% larger than that of pure Mg(BH4)2. In the neutron spectrum for Mg(BH4)2, the neutron flux in the energy range of less than 100eV drastically reduced as compared to those of other materials, due to the effect of boron.