Abstract
In the filtration of aerosols by a high-porosity fiber mat, the deposition of particles smaller than a few microns in diameter on a fiber depends on the combined effect of inertial impaction, Brownian diffusion, gravitational settling and direct interception, in the case where neither particles nor filters are electrically charged. This paper, after summarizing the results of our research on the collection efficiency of an isolated fiber due to the above four mechanisms, presents the dependences of the efficiency on the linear gas velocity and diameters of particle and fiber. In addition, a convenient method is proposed to predict the practical collection efficiency under arbitrary operating conditions. Prediction charts obtained in this manner can be made for the design of fibrous filters with porosity of more than 0.98.
