风速对自然通风教室内咳嗽飞沫液滴扩散的影响

The Effect of Wind Speed on the Spread of Cough Droplets in a Naturally Ventilated Classroom

本文利用Fluent软件模拟了两种进风风速下潜在呼吸道疾病患者连续两次咳嗽释放飞沫液滴的扩散过程,共模拟了100s的扩散情形。模拟结果表明:风速的提高明显加快了飞沫液滴的减少速度,但模拟时间内风速对教室内最终残留液滴数量的影响程度随咳嗽位置而变化。由于教室中心位置附近存在气流回流,因此在教室中心位置附近咳嗽时,飞沫液滴同样会向该位置左侧扩散,且初始时刻左右两侧的平均飞沫液滴浓度差值会随着风速增加有所提高,左侧浓度高于右侧。

Fluent software was used to simulate the diffusion process of droplets released by patients with potential respiratory diseases during two consecutive coughs under two wind speed conditions,and the simulation lasts for 100s in total.The results show that the increase in wind speed significantly accelerates the decrease in the number of droplets,but the degree of influence of wind speed on the final residual droplets in the classroom during the simulation time varies with the position of the cough,and due to the presence of airflow near the center of the classroom,when coughing near the center of the classroom,the droplets will also spread to the left of the position,and at the initial moment the droplet concentration difference on the left and right sides will increase with the increase of wind speed.