摘要
本文介绍一个适用于核事故条件的大气扩散模式 (粒子 烟团模式 )的建立与调试。模式在模拟大气扩散的粒子随机游走方法中引入类似于扩散烟团的核函数概念 ,用以反映单个随机游走粒子所代表的污染物质的空间影响范围。模式解决了随机游走粒子与核函数“烟团”耦合后反映扩散物理真实过程的一致性问题 ,在约 2 0 0km的范围内模拟结果与理论结果相一致。与代表实际大气典型扩散状况的高斯烟羽模式的结果进行定量比较 ,表明本模式结果在 1 0km的范围内总体合理 ,但在近源处有系统偏小。模式瞬时浓度的涨落相对于平均轴线浓度大体控制在 2 0 %～ 3 0 %的范围内。将模式应用于秦山地区的实际地形和气象条件进行实例测试表明 。
An atmospheric diffusion model was established for emergency environmental assessment in case of accidental release of radioactive materials from a nuclear power station. The model employed kernel technique in random walk simulation method to improve concentration modeling. Excellent agreement was shown by a test run of this model in comparison with theoretic result within the range of approximately 200 km. The output of the model is in good agreement with actual atmospheric diffusion property in the range of 10 km, though systematic underestimate existed for near source area. Statistical fluctuation of instant surface concentration was controlled in the range of 20%～30% to ground axial concentration of the average plume. The test regarding the application of this model to practical topography and meteorological conditions over Qinshan area showed the testing results reflect local complex diffusion processes and characteristics.
出处
《辐射防护》
CAS
CSCD
北大核心
2003年第5期293-299,共7页
Radiation Protection
基金
教育部高等学校骨干教师计划资助
