Study on virus droplet transmission in waiting halls of railway stations

By studying the airflow in the waiting hall of a railway station under full outdoor air condition, six-seat positions with airflow vortex are selected, which are not conducive to the transmission of droplets from the passengers’ cough, and the transmission of droplets from the cough of sick passengers at the six positions in the airflow field of the waiting hall is numerically simulated. The deposition rate of droplets, particle size distribution of deposition droplets, deposition speed, escape rate at air outlets, deposition time and complete air purification time of the waiting hall are analysed. The results show that 73.4% of the droplets from sick passengers are deposited on the surfaces of the wall and ground, 11.8% escaped from the air outlets, and 14.1% deposited on the surface of the passengers. The distance and length of the passenger seats directly affect the risk of passengers infecting virus. The larger the droplet size is, the faster the deposition speed is, and the greater the deposition rate is. The motion of droplets with particle size less than 30 μm in the high-space airflow field has a certain consistency, while the motion of droplets with particle size greater than 40 μm is more affected by gravity. 2.5% to 23.8% of droplets will be deposited on the passenger surface within 60 s, and the deposition speed is the fastest within 60 s. The fluctuation of the droplet suspension rate within 1.4% after 600 s will not greatly change the time required for air cleaning.