Study On Evaporation Characteristics Impact Of Indoor Microbial Aerosol

A large number of liquid particulate matter will be produced by human beings in their daily life during various operation processes.These liquid particles which suspended in the air ranged from 0.001 to 100?m,composed of multi-phase system with atmosphere were called atmospheric aerosols.A large part of the liquid matters are not single component,which may contain all kinds of ions and microorganisms,cause varying degrees of pollution to the environment.When the microorganis contained in the liquid particles are pathogens,it will become a major threat to human health.The force of the liquid particles will be in a changed dynamic processes during its evaporation.Therefore,it is important to study the evaporation process of the liquid particles to reasonably and effectively forecast and control the distribution of the liquid particles.We found that the current studies are focused on the discussion of numerical simulation methods and the derivation of theoretical formulas,different models of evaporation are proposed for the large and micron scale droplets.The experimental study on the evaporation process of liquid particles is less.At present the main experimental methods including droplet suspension,porous ball,fly drop experiment method and gas suspension(magnetic levitation)method,the study found that the rest of the group of points are included in the droplet evaporation process can be divided into two stages,droplet evaporation on tablet evaporation depends on whether the contact wire nail pierced.Based on the above backgroud,a simple experiment for the evaporation process of liquid matters in the indoor area is designed,With the method of plate droplet evaporation,by weighing quality changes during the process of droplet evaporation shows the microbe slurry droplet evaporation characteristics.This paper takes the experiment as the main research methods,including three parts:(1)evaporation experiments of different volumes of pure water droplets,the quality and morphological changes of 1?L?2?L and 5?L droplets on the superhydrophobic coated slides were analyzed.(2)In the subsequent experiment,the droplet volume was determined by the first part and the evaporation of NaCl solution droplets was studied.It was found that the presence of ions in the solution will significantly decrease the droplet evaporation rate,and the residue on the slide after the evaporation stage intuitively reflected the resulting “coffee ring effect”(3)The evaporation experiment of droplets with different microorganisms was carried out,and the results show that the evaporation in the microorganism droplets can be divided into the evaporation stage and the equilibrium stage.The evaporation stage of different kinds of microbes in microbial solution is different,and the fluctuation range of the equilibrium stage is also not the same.The results of this study are of great significance to predict the evaporation process of indoor microbial aerosols,which provides a theoretical basis for the design of rational air purification system.