相关实验视频
Updated: May 11, 2025

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Design and Construction of an Urban Runoff Research Facility
Published on: August 8, 2014
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中立边界层城市分散在规模均和不均的住宅建筑阵列中
Jonathan Retter1,2, David Heist2, R Chris Owen2
1ORAU ORISE Research Participation Program Hosted at EPA, Research Triangle Park, NC, USA.
概括
这项研究评估了城市环境中的AERMOD分散模型,发现其准确性随着统一和非统一的建筑阵列而下降. 简单的校正在统一的情况下提高了性能,但复杂的城市环境仍然存在挑战.
科学领域:
- 环境科学 环境科学
- 大气科学 大气科学
- 计算流体动力学的流体动力学.
背景情况:
- 准确的大气分散模型对于城市空气质量评估至关重要.
- 美国环境保护局 (EPA) 在监管方面依赖AERMOD模型.
- 现有模型可能需要对复杂的城市地形对污染物分散的影响进行改进.
研究的目的:
- 评估AERMOD模型在理想化的城市环境中的机械流和度预测的性能.
- 建立在均和非均建筑阵列中的分散特征的基线.
- 评估城市几何形状对污染物雾传播和度预测的影响.
主要方法:
- 在1:200尺度的边界层风洞中物理建模模拟城市环境.
- 粒子图像速度测量 (PIV) 用于测量速度和剪切应力概况.
- 碳化合物分析仪 (HCAs) 用于在定义的点测量乙度.
- 实验数据与AERMOD预测的比较,使用Factor of 2 (FAC2) 和Fractional Bias (FB) 的指标.
主要成果:
- 与没有建筑的场景相比,城市配置将AERMOD的FAC2性能降低了30.1%34.1%.
- 模拟度明显低于观察值,仅捕获最高测量值的48.1%62.4%.
- 简单的第一级校正改善了AERMOD在统一的城市案例中的表现,减轻了FB并增强了FAC2.
结论:
- 城市几何学显著影响高斯分散模型的准确性,如AERMOD.
- 该研究强调了需要在AERMOD中改进参数化,以更好地代表复杂的城市地形中的分散.
- 需要进一步的研究来开发针对不均的城市环境的强有力的纠正.
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