The effects of ventilation and floor heating systems on the dispersion and deposition of fine particles in an enclosed environment
The effects of ventilation and floor heating systems on the dispersion and deposition of fine particles in an enclosed environment
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通风和地暖系统对封闭环境中细颗粒物扩散和沉积的影响
DOI：
10.1016/j.buildenv.2017.08.049
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发表时间：
2017-11
影响因子：
7.4
通讯作者：
Cao Shi-Jie
中科院分区：
文献类型：
--
作者：
Zhou Yu;Deng Yelin;Wu Peng;Cao Shi-Jie
近年来，中国大部分城市遭受环境颗粒物污染，冬季尤为严重。北方大部分采暖建筑冬季缺乏新风系统，导致室内空气质量较差。本工作旨在通过实验测量和计算流体力学(CFD)方法来研究通风和地板供暖的室内环境中的颗粒扩散。考虑了两种通风系统，即自上而下送风。首先，通过CFD模拟对速度和颗粒浓度进行了实验验证。其次，模拟了非定常颗粒(直径为1μm)在不同进口风速(0.3、0.4和0.5m/S)和地板温度(293、298、303和308kK)下在通风地暖室内的扩散。粒子跟踪采用拉格朗日方法。结果表明，入口速度越高，颗粒浓度衰减越快。在相同的进气速度下，随着地板温度的升高，燃烧室内颗粒的去除速度加快。当进气速度为0.5m/S，地板温度为293s和308nK时，归一化浓度降至0.1时分别为391s和200s。随着进气速度和地板温度的升高，沉积在地板上的颗粒数量减少。本研究还发现，当地板温度为308℃时，采用下送风模式，归一化颗粒物浓度的去除时间缩短了15%。这些发现将有助于今后通风和供暖系统的设计。
Recent years, most cities in China suffer from ambient particulate matter pollution, especially in winter. The absence of fresh air system in most northern heating buildings in winter results in the poor indoor air quality. This work aims to deal with the particle dispersion in a ventilated and floor-heated indoor environment by using experimental measurements and computational fluid dynamics (CFD) methods. Two ventilation systems were considered, i.e., top & down supply. Firstly, experiments were conducted to validate the velocity and particle concentrations by CFD simulation. Secondly, unsteady particles (with the diameter of 1 μm) dispersion was simulated with different inlet velocities (i.e., 0.3, 0.4 and 0.5 m/s) and floor temperatures (i.e., 293, 298, 303 and 308 K) in a ventilated and floor-heated chamber. Lagrangian method was employed for particles tracking. It is found that the higher the inlet velocity, the faster particle concentration decayed. For the same inlet velocity, particles in the chamber were removed faster with the increase of floor temperature. When the inlet velocity was 0.5 m/s and the floor temperatures were 293 and 308 K, it took 391s and 200s respectively for normalized concentration decreasing to 0.1. The number of particles deposited on the floor decreased with the increase of the inlet velocity and the floor temperature. This study also identifies that when the floor temperature was 308 K, the removing time is reduced by 15% for normalized particle concentration with the down-supply ventilation mode. These findings would be facilitating for the future design of ventilation and heating systems.
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影响因子：
6.7
作者：
Xiaozhou Wu;B. Olesen;L. Fang;Jianing Zhao;Fenghao Wang
通讯作者：
Xiaozhou Wu;B. Olesen;L. Fang;Jianing Zhao;Fenghao Wang
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5.8
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Shi-Jie Cao;J. Meyers
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3.9
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Cao Shi-Jie;Zhu Dong-Hao;Yang Yin-Bao
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影响因子：
11.8
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D. Norbäck;Chan Lu;Yinping Zhang;Baizhan Li;Zhuohui Zhao;Chen Huang;Xin Zhang;Hua Qian;J. S
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