Fusion Engineering and Design ( IF 1.7 ) Pub Date : 2021-01-07 , DOI: 10.1016/j.fusengdes.2020.112221 Wenjie Yang , Qiusun Zeng , Chao Chen , Zhibin Chen , Jun Song , Zhen Wang , Jie Yu , Dmitry Yakovlev , Vadim Prikhodko
This paper presents the high flux neutron shielding design and extensive neutronics calculations of GDT based fusion neutron source ALIANCE. Neutron distribution of ALIANCE is strongly inhomogeneous along the axis: significant portion of the neutron flux is generated near the two mirrors, while the rest of it is spread over the remaining central volume of plasma. The shielding design includes 40 cm stainless steel as the main shielding layer and an additional 5 cm tungsten carbide shielding layer at mirror plugs to protect superconducting coils from neutron damage and reduce nuclear heating. The simulations have been carried out by using Monte Carlo transport code SuperMC with nuclear data library FENDL 3.1. Results show that the nuclear heating on the mirror coils can be reduced by more than two thirds with additional tungsten carbide shield, and fast neutron fluence by 30 %. The highest nuclear heating and the highest fast neutron fluence zones are located at the mirror coils, and the values are about 300 W/m3 and 9 × 1018 n/cm2 respectively, which meets the threshold of ITER superconducting coils. The specific activities of shielding layers are of order of 1012 Bq/kg. The structural materials’ specific activities will decrease to 4 × 1011 Bq/kg in one year after shutdown, and their decay heat will quickly drop below 2 kW/m3 after one day. Besides, all the structural materials of ALIANCE can be recycled by different recycling technologies. The modeling and calculations reported in this paper will be beneficial for the pre-conceptual engineering design of ALIANCE.
中文翻译:
基于GDT的聚变中子源ALIANCE的屏蔽设计和中子学计算
本文介绍了基于GDT的聚变中子源ALIANCE的高通量中子屏蔽设计和广泛的中子学计算。ALIANCE的中子分布沿轴非常不均匀:中子通量的很大一部分在两个反射镜附近产生,而其余部分则散布在其余的血浆中心体积上。屏蔽设计包括40厘米的不锈钢作为主要屏蔽层,并在镜插处附加一个5厘米的碳化钨屏蔽层,以保护超导线圈免受中子损坏并减少核辐射。通过使用带有核数据库FENDL 3.1的蒙特卡洛运输代码SuperMC进行了仿真。结果表明,使用额外的碳化钨屏蔽层可以将镜面线圈上的核加热降低三分之二以上,快速中子注量提高了30%。最高的核加热和最高的快速中子注量区位于镜线圈处,其值约为300 W / m分别为3和9×10 18 n / cm 2,满足ITER超导线圈的阈值。屏蔽层的比活度约为10 12 Bq / kg。停工后的一年中,结构材料的比活将降至4×10 11 Bq / kg,一天后其衰减热将迅速降至2 kW / m 3以下。此外,ALIANCE的所有结构材料都可以通过不同的回收技术进行回收。本文报道的建模和计算将对ALIANCE的概念前工程设计有益。