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Study on Simulation Method of Airborne Nuclear Radiation Contamination Field Based on Finite Point Source
DOI: 10.12677/nst.2024.122012, PDF, HTML, XML, 下载: 99  浏览: 180

Abstract: In order to establish an experimental platform of large-scale nuclear radiation contamination field for airborne radiation measurement, an infinite surface source simulation method based on point source is proposed in this paper. Monte Carlo simulation software was used to establish the point source range-detection efficiency response function, and the infinite surface source was divided into grids. Based on the integral mean value theorem, the equivalent conversion function of point source-circular line source-grid was established. On this basis, the equivalent point source distribution model was established. Results obtained by the Monte Carlo simulation show that the relative deviation between the total peak response of the detector through the equivalent point source distribution model and the infinite uniform surface source is 1.10%, and the experimental results show that the relative deviation between the total peak response of the detector through the equivalent point source distribution model and the infinite uniform surface source is 1.79%.

1. 引言

2. 理论基础

2.1. 圆形线源–无限大面源等效模型

Figure 1. Schematic diagram of ring integration

$f={\epsilon }_{面}A{S}_{面}=\underset{i=1}{\overset{n}{\sum }}{\epsilon }_{环i}A{S}_{环i}$ (1)

$\begin{array}{c}{f}_{环\text{i}}={\epsilon }_{环\text{i}}A{S}_{环\text{i}}={\int }_{{r}_{\text{i}-1}}^{{r}_{i}}{\epsilon }_{圆}\left(r\right)2\pi r{A}_{圆}dr\\ ={\epsilon }_{圆}\left({r}_{0}\right)2\pi {\text{r}}_{0}{A}_{圆}\left({r}_{i}-{r}_{i-1}\right)\\ ={\epsilon }_{圆}\left({r}_{0}\right)A{S}_{环\text{i}}\\ ={\epsilon }_{点}\left({r}_{0}\right)A{S}_{环\text{i}}\end{array}$ (2)

2.2. 圆形线源–无限大面源等效模型

Figure 2. Schematic diagram of grid integration

$f={\epsilon }_{面}A{S}_{面}=\underset{i=1}{\overset{n}{\sum }}{\epsilon }_{方格i}A{S}_{方格i}$ (3)

$\begin{array}{c}{f}_{方格i}={\epsilon }_{方格i}A{S}_{方格i}={\int }_{{r}_{\mathrm{min}}}^{{r}_{{}_{\mathrm{max}}}}{\epsilon }_{圆}\left(r\right)\theta \left(r\right){A}_{圆}rdr\\ ={\epsilon }_{圆}\left({r}_{0}\right)\theta \left({r}_{0}\right){A}_{圆}{r}_{0}\left({r}_{{}_{\mathrm{max}}}-{r}_{\mathrm{min}}\right)\\ ={\epsilon }_{圆}\left({r}_{0}\right)A{S}_{方格i}\\ ={\epsilon }_{点}\left({r}_{0}\right)A{S}_{方格i}\end{array}$ (4)

Figure 3. Schematic diagram of grid integral geometry

$\theta =|\mathrm{arcsin}\frac{{y}_{2}}{r}-\mathrm{arcsin}\frac{{y}_{1}}{r}|$ (5)

$\begin{array}{c}{f}_{方格\text{i}}={\int }_{{r}_{\mathrm{min}}}^{{r}_{{}_{\mathrm{max}}}}{\epsilon }_{圆}\left(r\right)\theta \left(r\right){A}_{圆}\text{r}dr\\ ={\int }_{{r}_{\mathrm{min}}}^{{r}_{{}_{x}}}{\epsilon }_{圆}\left(r\right)|\mathrm{arcsin}\frac{\sqrt{{r}^{2}-{a}^{2}}}{r}-\mathrm{arcsin}\frac{c}{r}|{A}_{圆}\text{r}dr\\ +{\int }_{{r}_{x}}^{{r}_{y}}{\epsilon }_{圆}\left(r\right)|\mathrm{arcsin}\frac{\sqrt{{r}^{2}-{a}^{2}}}{r}-\mathrm{arcsin}\frac{\sqrt{{r}^{2}-{b}^{2}}}{r}|{A}_{圆}\text{r}dr\\ +{\int }_{{r}_{y}}^{{r}_{\mathrm{max}}}{\epsilon }_{圆}\left(r\right)|\mathrm{arcsin}\frac{d}{r}-\mathrm{arcsin}\frac{\sqrt{{r}^{2}-{b}^{2}}}{r}|{A}_{圆}\text{r}dr\end{array}$ (6)

3. 蒙特卡罗模拟验证

Figure 4. Equivalent point source location

Table 1. Simulation results of equivalent point source

4. 物理实验验证

Figure 5. Point source equivalent physics experiment

Table 2. Simulation results of equivalent point source experiment

5. 结论

 [1] Shi, W., Machida, M., Yamada, S., et al. (2023) LASSO Reconstruction Scheme for Radioactive Source Distributions inside Reactor Building Rooms with Spectral Information and Multi-Radionuclide Contaminated Situations. Annals of Nuclear Energy, 184, Article ID: 109686. https://doi.org/10.1016/j.anucene.2023.109686 [2] 岳会国. 辐射应急监测技术[M]. 北京: 人民交通出版社, 2014. [3] 葛良全. 航空伽马能谱探测技术与应用[M]. 北京: 科学出版社, 2016. [4] 刘新华, 张永兴, 顾仁康, 等. NaI(Tl)航测谱仪对137Cs模拟面源的刻度[J]. 中国核科技报告, 2000: 170-180. [5] 胡明考, 张积运, 王新兴, 等. 木板模拟空气吸收伽玛射线试验介绍[C]//中国环境科学学会核安全与辐射环境安全专业委员会, 中国核学会辐射防护分会, 中华医学会放射医学与防护学分会, 中华预防医学会放射卫生专业委员会, 中国毒理学会放射毒理专业委员会. 第三次全国天然辐射照射与控制研讨会论文汇编. 2010: 6. [6] 汤彬. 核辐射测量原理[M]. 哈尔滨: 哈尔滨工程大学出版社, 2011: 438.