China Academy of Engineering Physics Institute of Fluid Physics, Mianyang, Sichuan, China.
China Academy of Engineering Physics, Mianyang, Sichuan, China.
Sci Rep. 2022 Feb 24;12(1):3148. doi: 10.1038/s41598-022-07180-w.
Radioactive aerosols harmful to humans are often produced in nuclear accidents, and their source term characteristics (total volume and particle size distribution) and dispersion patterns have important implications for accident response and hazard assessment. However, experimental studies of radioactive aerosols cannot be directly conducted in open space due to the hazardous nature of radioactive aerosols. In this study, silver was used instead of plutonium to study the aerosol source term under different specific internal energy inputs (SIEI) to simulate a low order explosion in an accident. Results show that aerosol release fraction (ARF) and respirable release fraction (RRF) of silver increase linearly with SIEI first, then varies in a range of 8% ~ 19%, with a turning point at SIEI of 1.4 MJ/kg. Analysis suggests an increase of difference between ARF and RRF with respect to SIEI. The size distribution of silver aerosol around 10 µm is influenced by SIEI significantly, which could be possibly attributed to the interactions between silver aerosol and ambient aerosol (solid HE products or rust). Comparison between the source term of silver and plutonium suggests that silver is a good surrogate of plutonium in studying aerosol for SIEI of MJ/kg level.
放射性气溶胶对人体有害,通常在核事故中产生,其源项特征(总量和粒径分布)和扩散模式对事故应对和危害评估具有重要意义。然而,由于放射性气溶胶的危害性,无法在开放空间直接进行放射性气溶胶的实验研究。在本研究中,使用银代替钚,在不同的特定内部能量输入(SIEI)下研究气溶胶源项,以模拟事故中的低阶爆炸。结果表明,银的气溶胶释放分数(ARF)和可吸入释放分数(RRF)随 SIEI 先呈线性增加,然后在 8%~19%的范围内变化,在 SIEI 为 1.4 MJ/kg 时出现转折点。分析表明,ARF 和 RRF 随 SIEI 的差异增加。粒径在 10 µm 左右的银气溶胶的分布受 SIEI 的显著影响,这可能归因于银气溶胶与环境气溶胶(固体高爆炸药产品或铁锈)之间的相互作用。银和钚的源项比较表明,在研究 SIEI 为 MJ/kg 级别的气溶胶时,银是钚的良好替代物。