一种脱方法来计算近场和远场暴露度
1School of Public Health, Environmental Health Sciences Division, 2121 Berkeley Way, University of California, Berkeley, CA 94740-7360, United States.
Annals of work exposures and health
|November 7, 2023
概括
一种新方法通过解方程式简化了近地/远地 (NF/FF) 区域中的污染物度的计算. 这种方法为NF/FF度提供了准确的近似值,改善了分散模型.
科学领域:
- 环境工程 环境工程
- 化学工程是化学工程的重要组成部分.
- 大气科学 大气科学
背景情况:
- 在近地/远地 (NF/FF) 区域中计算污染物分散涉及复杂的合方程.
- 导出污染物度函数CNF (t) 和CFF (t) 的分析解决方案的困难在很大程度上取决于排放率函数G (t).
研究的目的:
- 提出一种用于近似NF/FF污染物度函数的新方法.
- 为了使数学推导更容易,将合的NF/FF分散方程解.
- 为了验证拟议的近似方法的准确性.
主要方法:
- 分离NF和FF方程,将每个方程视为一个孤立的混合空间,具有不同的体积和空气流速.
- 导出FF区 (CWMR1(t)) 和NF区 (CWMR2(t)) 的独立污染物度函数,假设相同的排放率.
- 通过比较CWMR1 (t) +CWMR2 (t) 到CNF (t) 和CWMR1 (t) 到CFF (t) 的总和来验证近似值.
- 使用马尔科夫矩阵呈现离散时间数值解.
主要成果:
- 独立推导的FF和NF度函数的和 (CWMR1 ((t) +CWMR2 ((t)) 为结合的NF/FF度 (CNF ((t)) 提供了一个很好的近似值.
- 独立推导的FF度函数 (CWMR1 ((t)) 作为结合的FF度 (CFF ((t)) 的一个很好的近似.
- 拟议的脱方法大大简化了污染物度函数的近似计算.
结论:
- 与解决合方程相比,解方法提供了一种更容易接近的方法来接近NF/FF污染物度.
- 经过验证的近似值提高了分散模型的可行性,特别是当分析解决方案难以处理时.
- 还提出了基于马尔科夫矩阵的数值解决方案,用于对NF/FF分散系统的离散时间分析.
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