Research of Particle Filtration Efficiency Distribution in DPF

Abstract

As the diesel emission standards become stricter, diesel particulate filter (DPF)is being the dispensable post-treatment device reducing particulate emissions. In this paper, diesel particulate filter radial filtration efficiency distribution model is developed and formulated, based on microcosmic capturing mechanism and velocity distribution. The particle filtration efficiencies with different divergence angle, entrance velocity, channel width, wall thickness, are compared. The conclusion shows that the filtration efficiency of 7.5 nm diameter particles is highest, and the efficiency decreases while the particle diameter increases, until near240 nm diameter particles, and increases with particles diameter increasing to 1¦Ìmcontinuously. With decaying entrance velocity, channel width, and increasing wall thickness, radial location, the filtration efficiencies of different size particles ascend with different range.