微尺度室的计算流体动力学分析用于测量有机化学物质排放参数
Jack R Edwards1, Ching-Wei Huang1, Xiaoyu Liu2
1Department of Mechanical and Aerospace Engineering, North Carolina State University, Campus Box 7910, Raleigh, NC 27695-7910, USA.
Journal of hazardous materials
|November 11, 2023
概括
计算流体动力学 (CFD) 模拟模型在建筑材料扩散的微室中进行运输. 一个新的对流式质量转移模型改善了甲扩散预测.
科学领域:
- 环境科学 环境科学
- 化学工程是化学工程的重要组成部分.
- 建筑科学 建筑科学
背景情况:
- 通过建筑材料精确测量扩散传输对于室内空气质量至关重要.
- 微尺度室用于量化材料特性,但需要精确建模流体动力学和质量传输.
- 以前的模型经常简化了空气流,这可能会影响材料性质的准确性.
研究的目的:
- 在微尺度室内建模速度场和被动标量运输.
- 开发一种适用于各种建筑材料的对流式质量转移系数模型,包括诸如地毯之类的多孔材料.
- 将该模型集成到稳定状态系统中,用于预测建筑材料中甲扩散的情况.
主要方法:
- 计算流体动力学 (CFD) 模拟用于模拟空气流和标量运输.
- 稳定,层状流的假设与热线气流测量测量进行了比较.
- 开发了一种对流式质量转移系数,与雷诺兹数,施密特数和材料孔隙性相关.
主要成果:
- CFD模拟通常低于预测近地表速度,在更高的流速和多孔材料中准确度提高.
- 建立了一个强大的对流式质量转移模型,考虑了流动动力学和材料特性.
- 预测甲通过乙烯基地板,石膏壁板和地毯的扩散和分离系数与现有的文献值保持一致.
结论:
- 开发的对流式质量转移模型提高了通过建筑材料预测气态甲扩散的准确性.
- 对于这种采样装置配置,对混合良好的上室的假设进行了验证.
- 细化后的CFD建模在微量环境采样设备中提供了对运输现象的宝贵见解.
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