Open AccessShielding design of the multi-purpose reflectometer of China spallation neutron source
Author(s) -
沈飞,
梁泰然,
Fei Shen,
TR Liang,
Wen Yin,
Qian Yu,
TS Zuo,
Ze Yao,
Tao Zhu,
TJ Liang,
左太森
Publication year - 2014
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.63.152801
Subject(s) - electromagnetic shielding , spallation neutron source , variance reduction , monte carlo method , neutron source , shutter , neutron , nuclear engineering , neutron transport , neutron radiation , optics , materials science , computational physics , nuclear physics , physics , engineering , statistics , mathematics , composite material
The shielding design employing the Monte Carlo simulation code of MCNPX 2.5.0 for multi-purpose reflectometer of China spallation neutron source (CSNS) is introduced, including the shielding needs, radiation source terms, calculating methods and simulation results, etc. Various radiation source terms such as the moderator leakage source term, and the neutron guide loss source term etc. are taken into account in the simulation, and step-by-step calculation method and variance reduction methods such as source angular biasing, source energy biasing, and geometry splitting, are adopted to improve the computing speed while the precision of the results is guaranteed. In the shielding design of instrument transport beamline, second shutter, and scattering room etc., the final shielding parameters are determined by comparing the shielding need under different operating conditions, to ensure the dose rate below the 2.5 Sv/h limitation in accessible locations outside the shielding.