基于WRF的“脏弹”恐怖袭击辐射剂量评估方法

提出了一种基于WRF模式的"脏弹"恐怖袭击辐射剂量计算方法。提出了对源项、地表干沉降、湿沉降量的放射性衰变修正方案;并利用该方法计算"脏弹"恐怖袭击造成的辐射剂量。选取某地点作为固定的"脏弹"释放位置,模拟了不同气象条件下的辐射剂量分布。结果表明,以干沉降为主的地表沉降分布,在风场作用下呈条状分布;以湿沉降为主的地表沉降分布,在降水作用下呈块状分布。模拟结果反映了降水对"脏弹"恐怖袭击污染物分布的重要影响。结论表明,模型对降水及沉降过程具有较好的刻画能力,可用于全部放射性污染物质的环境辐射剂量评估。

An Assessment Method of Radiation Dose under Dirty Bomb Terrorism Based on WRF

In this paper, an assessment method of radiation dose under dirty bomb terrorism based on WRF is proposed. An upgraded model is developed by implementing the radioactive decay process into source term and ground dry and wet deposition, which is to be used to calculate the radiation dose caused by dirty bomb terrorism. In this paper, case studies with dirty bomb released at a fixed point are established to simulate the distribution of radiation doses under different meteorological conditions. The results suggest that the total deposition, which is dominated by dry deposition, shows a strip distribution mainly affected by wind fields; while the total deposition, which is dominated by wet deposition, shows a block distribution mainly affected by precipitation. The results show a significant impact of precipitation on the distribution of radionuclides released from a dirty bomb terrorist attacking, which prove that the model can well describe the precipitation and deposition of radionuclides so that it can be used to predict the radiation dose for all types of radionuclides under dirty bomb terrorist attacking.