室内颗粒物和二氧化碳浓度是评价室内空气质量的主要指标。基于直接蒸发冷却段的二维填料筛分模型,多孔介质模型用于水填料段的模拟,通过调节不同工况下的淋水密度和气流速度来模拟颗粒的过滤效率。用于改变排风出口位置和控制空调使用的三维教室模型模拟了室内热环境和污染物浓度的变化。采用欧拉法和拉格朗日法对直接蒸发段室内流场和颗粒筛分进行了分析,分别。结论表明,蒸发冷却和地层通风空调系统在教室中的应用,排气口的位置会影响学生呼吸区域的二氧化碳浓度。水填料段可以有效降低室内供应的颗粒和二氧化碳的浓度。通过直接蒸发冷却段的室外空气中的颗粒基于扩散的过滤效率,惯性碰撞,和拦截受到颗粒大小的综合影响,向前的风速,和喷水密度。颗粒的过滤效率随着喷淋水的密度增加而增加。随着迎面风速的增加,粗颗粒物的过滤效率高于细颗粒物。研究结果有助于政策制定者决定是否在学校安装蒸发冷却空调,并确定哪些排气出口位置对改善室内空气质量最有效。
Indoor particles and carbon dioxide concentration are major indices to evaluate indoor air quality. Based on the two-dimensional filler sieving model of the direct evaporative cooling segment, the porous media model was used for the simulation of the water filler section, the filtering efficiency of particle was simulated by adjusting the water drenching density and airflow velocity in different operating conditions. The three-dimensional classroom model used to change the exhaust
outlet position and control the use of air conditioners simulated the indoor thermal environment and the changes in pollutant concentration. The Euler method and Lagrangian method were used to analyze the indoor flow field and particle sieving in the direct evaporation section, respectively. Conclusions show that in the application of evaporative cooling and stratum ventilation air conditioning system in classroom, the position of the exhaust port affects the concentration of carbon dioxide in the student\'s breathing area. The water filler section can effectively reduce the concentration of particle and carbon dioxide supplied indoors. The filtration efficiency of particle in outdoor air passing through the direct evaporative cooling section based on diffusion, inertial collision, and interception is affected by the combined effect of particle size, onward wind speed, and water spray density. The filtration efficiency of particle increases as the density of the spray water increases. With the increase of head-on wind speed, the filtration efficiency of coarse particulate matter is higher than that of fine particulate matter. The research results help policy makers decide whether to install evaporative cooling air conditioning in schools and determine which exhaust
outlet positions are most effective in improving indoor air quality.