Software model of airborne propagation SARS-COV-2 in the air

The danger of the spread of the COVID virus disease is due to propagation of the exhaled virus cloud in the natural conditions of human habitation. Modeling the spread of a viral cloud of airborne droplets makes it possible to assess the conditions for limiting its spread. Mathematical tools and software modeling tools are used to obtain a dynamic picture of the spread of the virus cloud. The results of software modeling of SARS-COV-2 virus spread in air in the form of aerosol saliva particles <5 microns formed by infected person breathing are presented. The comparative sizes of aerosol particles of the exhaled air-drop mixture and smoke particles in the air are given. A conclusion is made about the thermodynamic convection process of aerosol cloud propagation in the air. The software model is developed on the basis of the Laplace equation with zero boundary conditions and initial conditions – an instantaneous source in the center of the volume. The simulation is carried out and conclusions are drawn about the influence of temperature on the flash attenuation. Assumptions are made about the need to use an absorbing material to reduce the flash attenuation time. From theoretical and practical points of view, it is determined that the process of SARS-COV-2 propagation in the air is caused by diffusion and convection process of the air-drop mixture flow in the air. Such a flow is similar to the spread of smoke and fog in the air. The study takes into account physical phenomena such as diffusion and convection in the air.

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