The problem of viral and microbial contamination has received extensive and high attention from scholars at home and abroad. A great deal of information and research has demonstrated that droplets containing organisms such as viruses and bacteria can be airborne, so it is extremely important to study the movement and transmission patterns of the particles. Human coughing and sneezing are the main sources of viral droplets and are the focus of this paper. This topic starts with a theoretical approach to investigate the propagation law of microbial aerosols in the air, combined with the characteristics of droplets, to establish a model of microbial particle dispersal. And based on the Lagrangian method, the model is simplified and the 4th order standard Runge-Kutta algorithm is used to numerically solve the differential equations based on the Matlab platform, so as to analyse the effects of factors such as jet velocity, ambient wind speed and the size of the exhaled virus particles occurring on the particle motion. The evaporation of particles also has a relatively large effect on the motion of smaller sized particles, which after complete evaporation will will float in the air and will no longer hit the ground. Ultimately, the analysis of particle movement distances leads to recommendations for the prevention of airborne infectious disease transmission.

Jiawen Han. Movement Mechanisms and Numerical Simulation of Virus-containing Exhaled Droplets. Frontiers in Medical Science Research (2021) Vol. 3 Issue 6: 52-63. https://doi.org/10.25236/FMSR.2021.030610.

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