Research On The Control Technology Of Virus Air Transmission

In the history of mankind,infectious diseases have brought great disaster to people,and the struggle between humans and infectious diseases has been in progress.There are many ways to spread infectious diseases.Many severe infectious diseases can be transmitted by air or droplets(such as SARS,Hantavirus,New Coronavirus,etc.).People breathe air all the time,so viruses that can be transmitted through the air need our special attention.How to better control the spread of viruses in the air has become a problem that has been widely concerned and urgently needed to be solved by the society.Based on this,this paper studies the characteristics of aerosol particles,the main carrier of virus airborne transmission,and how to effectively control them.First,this article takes the negative pressure isolator in an ABSL-3 laboratory as the research object and establishes a three-dimensional model.The influence factors of aerosol particle concentration and particle size distribution were simulated and analyzed.The simulation results show that increasing the number of air changes will increase the particle concentration in the airflow vortex area inside the isolator,and decrease the particle concentration in other areas.Increasing the number of air changes and the temperature of the air supply can increase the average particle size of the particles.Reducing the number of air changes can significantly increase the proportion of 0-0.01μm particles in the 0-0.1μm particle size range.An ordinary double ward was used as the object to build a model.Based on the LES turbulence model,the diffusion of human exhaled aerosol particles under the effect of thermal plumes of different intensities was simulated.The simulation results show that the distribution rules of thermal plumes generated by the human body model at different room temperature tend to be consistent,and the speed of the thermal plume increases with the difference between the surface temperature of the human body model and the room temperature.The diffusion distance and speed of the exhaled particles of the human body are related to the intensity of the heat plume,which increases as the intensity of the heat plume increases.Based on the previous research,the control effect of different ventilation modes on human exhaled particulate matter in the ward was simulated.The simulation results show that when the number of ventilation is 10 ACH,among the four air supply modes of sidewall supply and up return,sidewall supply and down return,down supply and top return,and down supply and sidewall return,the down supply and top return is the best way to control the diffusion of exhaled particles program.Increasing the number of air changes exacerbates the diffusion of particulate matter,which is not conducive to the removal of particulate matter.Reducing the number of air changes can better control the particulate matter near the roof,which facilitates the removal of particulate matter.When the ventilation frequency is 5ACH,the proportion of particles in the vertical height range of 2.7m-3m reaches 36.33%.