Study on Diffusion Law of Aerosol Particles in Indoor Human Droplets

This paper studies the movement characteristics of aerosol particles produced by human cough behavior, and on this basis, the influence of different air distribution forms on the distribution and movement characteristics of aerosol particles in simple indoor human body is compared, so as to obtain the best air distribution form. Using computational fluid dynamics (CFD) method, a 1:1 human body model was established according to the actual human body ratio, and a mathematical model of aerosol particle movement was established using DPM model. The diffusion law of aerosol particles exhaled by human body was simulated under three ventilation modes of mixed ventilation, displacement ventilation and floor air supply. The results show that the droplet particles move forward and down and diffuse after being ejected from the human mouth, and the particle mass concentration is gradually diluted in the air. Larger diameter of particle deposition to the end of the small size of particles is influenced by the human body thermal plume "floating" suspension aerosol formation, different airflow organization forms can cause significant disturbance to particle diffusion, including displacement ventilation in dilute particle mass concentration has the best performance, followed with floor board air supply and mixed ventilation performance is relatively poor.