Abstract

A three-dimensional model of an enclosed air-conditioned space was established. Numerical simulation was conducted for the temperature distribution in the enclosed space with the air conditioner turned on using computational fluid dynamics, and the movement track of aerosol droplets exhaled by a patient in the enclosed space was traced using the discrete phase model based on the Eulerian–Lagrangian method. The analysis shows that, after the air conditioner is turned on, the velocity and temperature of outflowing air from the air conditioner greatly influence the temperature field and the movement track of aerosol in the enclosed space. With the change of intake air temperature, there is little difference in the absorption of aerosol by air conditioning; When the air velocity of outflowing air from the air conditioner is 0.8 m/s-2m/s, the amount of aerosol absorbed by the air conditioner increases with the increase of air velocity of outflowing air from the air condition. Equipping the air conditioner with an aerosol filter can prevent the aerosol droplets from exiting of the air conditioner again and decrease the quantity of aerosol particles in the enclosed space, thus reducing the risk of airborne viruses infecting susceptible people. In some public places where central air conditioning is used, aerosol filters can also avoid transmitting aerosols to other spaces through the central air conditioning system.

摘要

建立了封闭空调空间的三维模型。利用计算流体力学对空调开启时密闭空间内的温度分布进行数值模拟，并利用基于欧拉-离散相模型追踪患者呼出的气溶胶液滴在密闭空间内的运动轨迹。拉格朗日方法。分析表明，空调开启后，空调出风的速度和温度对封闭空间内的温度场和气溶胶的运动轨迹影响很大。随着进气温度的变化，空调对气溶胶的吸收差异不大；当空调出风风速为0.8m/s-2m/s时，空调器吸收的气溶胶量随着空调器流出空气的风速的增加而增加。在空调上安装气溶胶过滤器，可以防止气溶胶飞沫再次从空调中逸出，减少密闭空间内的气溶胶颗粒数量，从而降低空气中病毒感染易感人群的风险。在一些使用中央空调的公共场所，气溶胶过滤器还可以避免气溶胶通过中央空调系统传播到其他空间。在空调上安装气溶胶过滤器，可以防止气溶胶飞沫再次从空调中逸出，减少密闭空间内的气溶胶颗粒数量，从而降低空气中病毒感染易感人群的风险。在一些使用中央空调的公共场所，气溶胶过滤器还可以避免气溶胶通过中央空调系统传播到其他空间。在空调上安装气溶胶过滤器，可以防止气溶胶飞沫再次从空调中逸出，减少密闭空间内的气溶胶颗粒数量，从而降低空气中病毒感染易感人群的风险。在一些使用中央空调的公共场所，气溶胶过滤器还可以避免气溶胶通过中央空调系统传播到其他空间。