随着对舰艇核安全的关注度越来越高，对辐射监测仪器性能提出了更高的要求。本文对基于球形正比计数器的中子剂量率仪探头结构进行研究，采用Ansys有限元分析软件对直径为100 mm的Benjamin球形正比计数器进行建模计算，通过调整支撑子直径、绝缘子直径、绝缘子距阳极丝端部距离、支撑子侵入球体距离4个结构参数，分析对阳极丝附近雪崩区域电场均匀性的影响，并寻找优化方案。结果表明，可通过将支撑子侵入球体3 mm距离，使球体端部结构由直径25.7 mm缩小至16 mm，从而减小对探测器方向响应性能的影响。
As the nuclear safety of ships attracts more attention, the requirements for the performance of radiation monitoring instruments are getting higher. This work optimizes the design of the probe structure of a neutron dosimeter based on a spherical proportional counter. The Ansys finite element analysis software is used to model and calculate the Benjamin spherical proportional counter with a diameter of 100 mm. By adjusting the diameter of the supporter, the diameter of the insulator, the distance between the insulator and the end of the anode wire, and the distance of the supporter entering the sphere, the influence law of the electric field uniformity in the avalanche region near the wire is studied, and the optimization scheme is found. The results show that the diameter of the end of the sphere can be reduced from 25.7 mm to 16 mm by intruding the supporter into the sphere at a distance of 3 mm, thereby reducing the influence on the directional response performance of the detector.
2023,45(20): 217-221 收稿日期：2022-9-22
DOI：10.3404/j.issn.1672-7649.2023.20.043
分类号：TL48
作者简介：肖枫(1993-),男,硕士研究生,助理工程师,研究方向为舰船核环境工程
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