Performance of Elecrically Augmented Fibrous Filters,Measured with Monodisperse Aerosols

摘要

A study of the performance of filters in an extenal electric field has been carried out in controlled conditions using monodisperse aerosols with a charge distriution close to a Boltzmann.The effsic agreemetn with existing theory for the capture of particles by polarization forces and indicate that this process is dominant,although other filtration processes are also significant,particularly when the electric field is low.Reasonable correlation betweensingle fiber efficiency and t dimensionless parameter for capture the inclusion of the hydrodynamci factor into the calculation,ut this does not remove all discrepancy.If filters are exposed to an electric field for a protracted period,a small peristent residual polarization of the fibers is observed.Loading the filter with aerosol in the laboratory has little effect on its performance,though eventually the aerosol captured in the vicinity of the live electrode caused shorting out.