The Numerical Smulation Research Of Inhalable Particles Separated In Sound Waves

Inhalable particles are one of the main atmospheric pollutants,which concentrates many hazardous substances and jeopardizes human health. Inhalable particles have the following special features: minor radius, multitude in number and suspended in the air easily, accordingly conventional dust-removing equipments remove them very difficultly. One important effective method to deal with the inhalable particles is to agglomerate them into large ones, so that the conventional dust-removing equipments can gather them more efficiently. Acoustic agglomeration is an efficient way to make the inhalable particles aggregation. When the inhalable particles occur a collision each other, the collision deduce agglomeration and the average particle size increases in a short period of time. The acoustic agglomeration is considered to be an easy, feasible and effectual way to seize inhalable particles.In this paper, the pressure change of sound wave is considered as main force on the particle, and the fluid field and the particle trajectory in pretreatment equipment were simulated, and the particles collide in the fluid field can be predicted numerically. The turbulent flow and particles trajectory in the cyclone separator were simulated numerical detailed too, and it is shown that small particles are easily ejected following airflow and are relatively difficult to collect than big particles. On the basis of former research, the elimination proficiency was calculated. Although the colliding particles can observe by simulating, the elimination proficiency is not increase obviously. The main reason is that we didn't consider the aerosol dynamics of acoustic agglomeration, and the particles agglomeration can not be shown in present simulation.And then the aerosol dynamics of acoustic agglomeration based on the orthokinetic interaction was given and the aerosol dynamics equation was solved again. The solving results indicate that the concentration of the small size particle decreases and the concentration of the larger size particle increase. The two different size concentrations of particles were employed to simulate particle trajectory passing the cyclone separator, and count the number of the particles collected to analyze elimination proficiency. When considering the aerosol dynamics, the statistics indicates that the elimination proficiency increased. It is shown that the aerosol dynamics is the key for particles agglomeration.