Liang Tai-ran, Shen Fei, Liang Tian-jiao, Yin Wen, Yu Quan-zhi, Yu Chun-xu
Department of Physics, Nankai University, Tianjin 300071, China Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China The School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China.
Radiat Prot Dosimetry. 2014 Dec;162(3):208-14. doi: 10.1093/rpd/nct343. Epub 2013 Dec 26.
The Chinese spallation neutron source (CSNS) is a high-performance pulsed neutron source, having 20 neutron beamlines for neutron scattering instruments. The shielding design of these beamlines is usually needed for Monte Carlo (MC) calculation, and the use of variance reduction methods is critical to carrying out an efficient, reliable MC shielding calculation. This paper discusses the source biasing method based on actual source term and geometry model of a CSNS neutron beamline. Dose distribution throughout the geometry model was calculated with the FLUKA MC code. Full analogue calculation and biased calculation were compared, and it was validated that the source biasing method can effectively promote the calculation efficiency.
中国散裂中子源(CSNS)是一台高性能脉冲中子源,拥有20条用于中子散射仪器的中子束线。这些束线的屏蔽设计通常需要进行蒙特卡罗(MC)计算,而使用方差缩减方法对于进行高效、可靠的MC屏蔽计算至关重要。本文讨论了基于CSNS中子束线实际源项和几何模型的源偏置方法。使用FLUKA MC代码计算了整个几何模型中的剂量分布。比较了全模拟计算和偏置计算,验证了源偏置方法可以有效提高计算效率。