Numerical Simulation of Droplet Transport in Bus

doi:10.12068/j.issn.1005-3026.2021.05.018

Abstract

Abstract: Based on the numerical simulation method of computational fluid dynamics， the evaporation， sedimentation and diffusion of droplets produced by coughing when the air velocity is 0.25~2m/s and the passengers are in the front， middle and rear of the car compartment are studied. The results show that the droplets evaporate quickly after spraying. When the air inlet velocity is small， the large-particle droplets will settle rapidly， and the small-particle droplets will stay in the space for a long time and have a large influence. When the air inlet velocity is high， the large droplets stay in the space longer and spread farther， while the small droplets stay in the space for a short time. Considering comprehensively， the recommended air inlet speed of the carriage is 1m/s under the conditions of this model. When the patient is in the front of the vehicle， the droplets mainly settle on the vehicle wall， followed by the ground. When the patient is in the middle and rear of the car， the droplets mainly settle on people and seats， followed by the ground. Compared with the front and the middle， the droplets have a larger impact when the patient coughs in the back of the compartment. This study can provide guidance for the correct understanding of droplet propagation， ventilation and elimination in bus.

Key words: bus; droplet transport; ventilation; patient location; numerical simulation

CLC Number:

X951

LIN Xiu-li， ZHANG Ying-ying， LIU Jing-xian. Numerical Simulation of Droplet Transport in Bus[J]. Journal of Northeastern University(Natural Science), 2021, 42(5): 726-733.

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