基于修正高斯烟团模型的SO_(2)瞬时排放扩散研究

Dispersion of Transient Emissions of SO_(2) Based on the Modified Gaussian Puff Model

大气腐蚀不仅危害人类身体健康,而且会对暴露在大气环境中的工业设备造成腐蚀危害。SO_(2)是主要的大气污染物之一,对其扩散的研究可以预测近污染源地区大气中SO_(2)浓度分布,进而为采取监测治理措施提供理论支撑。高斯烟团模型通常用来模拟在小风静风条件下稳定污染点源连续排放的大气扩散问题,但对稳定污染点源瞬时排放(排放一段时间后不再排放)的研究较欠缺。提出一种修正的高斯烟团模型,将稳定污染点源瞬时排放污染物浓度扩散问题建模为排放时间内有限个烟团的叠加,分别讨论了烟团扩散时间小于或等于排放时间、扩散时间大于排放时间条件下稳定污染点源瞬时排放的大气扩散模型,并通过实例对提出的修正高斯烟团模型进行了仿真模拟试验。结果表明:修正后的高斯烟团模型能够模拟稳定污染点源连续排放和瞬时排放两种情况下污染物SO_(2)浓度分布,且模拟结果更符合实际情况。该研究结果可为近污染源地区大气中SO_(2)浓度的实时预测提供更为有效的方法。

Atmospheric corrosion is hazardous to not only human health but also industrial equipment exposed to the atmosphere.Because SO_(2)is one of the main atmospheric pollutants,the study of its diffusion can help predict the concentration of SO_(2)in atmosphere near the pollution source,which provides theoretical support for monitoring and treatment measures.The Gaussian puff model is often used to simulate the continuous diffusion of stable pollution point sources under the conditions of low wind or quiet wind.Ho-wever,the transient emission of stable pollution point sources(no emission after a while)is less studied.Therefore,we propose a modified Gaussian puff model to simulate the transient diffusion of stable pollution point sources.Our model regards the instantaneous emissions as the superposition of a finite number of puffs and discusses the diffusion of a stationary point source with diffusion time less than or equal to emission time and with diffusion time longer than emission time,respectively.Then we conduct simulation case study based on the proposed modified Gaussian puff model.The results show that the modified Gaussian puff model can simulate SO_(2) concentration distribution under the continuous emission or instantaneous emission of a stable pollution point source,which is more practical and provides a more effective method for the real time prediction of SO_(2)concentration in atmosphere near pollution source.