基于蒙特卡罗法的缓发中子探测装置设计

Design of Slow⁃Burning Neutron Detection Device Based on Monte Carlo Method

为提高缓发中子探测装置的灵敏度,设计了基于蒙特卡罗法的缓发中子探测装置。采用蒙特卡罗N⁃粒子传递代码(MCNP)程序和Geant4程序解决复杂螺旋管建模难点问题,完成基于BF3探测器的缓发中子探测装置模型建立及粒子输运设计,从而计算缓发中子探测效率。计算结果表明,可能由于MCNP和Geant4程序对H原子的慢化数据库或物理模型不一致,引起两种方法计算的结果误差为17%。但BF3探测器对螺旋管内中子探测效率均较高,不影响缓发中子探测装置的螺旋管状源项设计。该设计对中子探测装置的效率设计具有一定的借鉴意义。

To improve the sensitivity of the slow⁃burning neutron detection device,a slow⁃burning neutron detection device based on Monte Carlo method is designed.The Monte Carlo N⁃particle transport code(MCNP)program and Geant4 program are used to solve the difficult problem of modeling complex spiral tubes and complete the modeling and particle transport design of the slow⁃burning neutron detection device based on the BF3 detector,so as to calculate the slow⁃burning neutron detection efficiency.The calculation results show that the error of the results calculated by the two methods is 17%,probably due to the inconsistency of the slowing database or physical model of H atoms by MCNP and Geant4 program.However,the BF3 detectors all have high efficiency for neutron detection in spiral tubes,which does not affect the design of the spiral tubular source term of the slow⁃burning neutron detection device.The design is of some significance for the efficiency design of neutron detection devices.