Abstract: The coronavirus disease 2019 (COVID-19) has spread rapidly in a short period in the whole world. It has been an international epidemic disease. The transmission and spread of respiratory droplets which contain viruses is an important way for the spread of COVID-19. In this paper, numerical investigations of the diffusion process of cough droplets under different conditions such as relatively closed rooms, elevators, high-speed rail cabin, and aircraft cockpit were conducted based on the Euler-Lagrange method.
The results show that the relatively enclosed space adopts the side-wall convection ventilation or ceiling ventilation modes, which
reduce the disturbance and residence time of the droplets in the enclosed space. It also inhibits the spread of virus-borne droplets, and enhances the emission of droplets.