高架排放及大粗糙地形条件下稳定度分类方法对大气扩散计算结果的影响

本文介绍在高架排放及大粗糙地形条件下稳定度分类方法对大气扩散计算结果的影响。采用五种不同的稳定度分类方法,对在西德卡尔斯鲁厄核研究中心(KfK)进行的一系列(22次)高架源(H=100m)大粗糙地形(地面粗糙长度 Z_0≈1.5m)条件下的大气扩散示踪试验数据作了统计分析。结果表明:在大粗糙地形及高架排放条件下,用高斯烟羽模式预报的归一化扩散因子与其实测值符合较好;对同一系列示踪试验数据,用不同稳定度分类方法分析处理会得出不同的弥散系数;在采用推荐的扩散参数进行环境评价时,最好使用与推荐者采用的相同的稳定度分类方法

INFLUENCE OF STABILITY CLASSIFICATION ON ATMOSPHERIC DIFFUSION CALCULATIONS FOR ELEVATED RELEASES OVER A TERRAIN OF MAJOR RONGHNESS

The influence of stability classification on atmospheric diffu-sion calculations for elevated releases over a terrain of major roughness isdescribed.A series(22)of atmospheric tracer experiments with 100m releaseheight have been performed at the kernforschungszentrum karlsruhe(KfK)ofwest Germany over a terrain of major roughness(Z_0=1.5m).The concen-tration data of the tracers are statistically analysed ln which 5 methods ofstability classification are used.The results show that the normalized diffu-sion factors predicted by Gausslan plume dispersion model ls in good agree-ment with the observed ones for elevated releases over a terrain of major roughness.Different sets of dispersion parameters could be obtained for thesame series of atmospheric tracer experiments if different methods of classi-fieation are applied.The same method of stability classification should beused for the application of these dispersionparameters to evaluate the env-ironment impact.Institutc for Radiation Protection,MNI)Kernforschungszentrnm Karlsruhe Gmbh,Karlsruhe West Germany