海岸地区基于AERMOD的热力内边界层对大气污染物扩散影响的模拟研究

AERMOD based simulation for the influence of thermal internal boundary layer on air pollutant diffusion in coastal area

海岸地区热力内边界层(TIBL)对大气污染物扩散具有重要影响。选取杭州湾地区某区域为模拟区,采用一个TIBL高度的简单计算模式模拟模拟区的TIBL高度,将其耦合到空气质量模式AERMOD中,并对AERMOD的相关模块和参数进行了相应的修改,再分别利用原AERMOD和改进后的AERMOD,模拟了不同污染源情景下的大气污染物地面浓度分布。结果表明,在多数情况下,由于TIBL对于大气污染物扩散空间的限制,大气污染物的地面最大浓度有所升高,地面浓度的高值区范围也有所增加,具体影响特征取决于污染源与TIBL的相对高度以及污染源距离海岸的相对位置。

Thermal internal boundary layer（TIBL） in coastal area has an important influence on air pollutant diffusion. This research is done with observational data of the boundary layer in the northern coastal area of the Han- gzhou Bay. The author improved AERMOD model by established a simple one T1BL height computational model, coupled it into the widely-used air quality model AERMOD, and adjusted relevant modules and parameters of the model. The improved AERMOD model and old AERMOD model were employed to simulate the impact of the TIBL on air pollutant surface concentration under different situations. The results showed that for most eases, due to limi- tation of the TIBL to diffusion, the peak values and the range of high concentrations were obviously increased. The feature of the impact is determined by the relative height of the source and the TIBL, and the distance of the source to the sea shore.