美国AERMOD模型与中国大气导则推荐模型点源比较

The Comparison of Point Source between US AERMOD Model and China Recommended Model of Atmosphere Guideline

介绍了美国AERMOD模型和中国大气导则推荐模型一般浓度公式,通过大气稳定度和扩散参数的确定、复杂地形处理和对流条件下污染物扩散等原理方面的比较认为,AERMOD模型优于大气导则推荐模型.以美国环境保护局(USEPA)2个试验场Clifty Creek(平坦地形)和Lovett(复杂地形)的数据资料为比较数据,分别用AERMOD模型和大气导则推荐模型计算SO2小时质量浓度,在Pasquill 6类稳定度下用相对偏差(FB)、预测值与观测值的比率(RHCR)及图形法(Q-Q图)等进行模型比较,结果表明:在RHCR和FB中,AERMOD模型除个别值外,其他均好于大气导则推荐模型;而大气导则推荐模型存在接近或大于模型可靠性界限0.67(0.66和0.74),说明其可靠性比AERMOD模型差;图形法比较中,强不稳定和不稳定下AERMOD模型明显好于大气导则推荐模型,而大气导则推荐模型预测值明显偏低,其他稳定度下结果相差不大.研究认为:在平坦地形和复杂地形条件下,AERMOD模型点源预测值均优于大气导则推荐模型,并从原理上进行了解释.

The general concentration formulae of US AERMOD Model and China Atmosphere Guideline Recommend Model were introduced. In comparison of theories of atmosphere stability and dispersion parameters determination, complex terrain treatment, and pollutant dispersion in convective condition, etc., it is indicated that AERMOD Model is better than Atmosphere Guideline Recommend Model. Using two US EPA field studies data of Clifty Creek （fiat terrain）and Lovett （complex terrain）as model comparison data, one-hour average concentration was calculated respectively by US AERMOD Model and Atmosphere Guideline Recommend Model. FB and RHCn （statistical methods） and Q-Q plots （graphics） were used in six Pasquill stabilities for the comparison of models. The results indicate： Excepting one or two values, AERMOD model is better than Atmosphere Guideline Recommend Model in RHCR and FB. Some values such as 0.66, 0.74 etc. nearly reach or exceed the threshold reliability of the models, 0.67. This indicates that Atmosphere Guideline Recommend Model is less reliable than AERMOD Model. In Q-Q plots, with strong unstable and unstable conditions, Atmosphere Guideline Recommend Model＇s prediction concentrations are obviously lower and the AERMOD Model＇s prediction concentrations are obviously better, while the prediction results of the two models under other stabilities are similar. It is concluded that AERMOD Model is better in prediction concentration of point sources, which has been interpreted in theory.