The influence of filtration velocity on the full-sized fibrous filter performance

摘要

Filtration velocity is a fundamental parameter that influences fibrous filtration performance. The previous work focuses on the effect of velocity on filtration performance, mainly using downsized filters, a flat sheet media or numerical methods. In this study, the actual performance of the full-sized fibrous filters was simulated according to standard test procedures, ISO 16890:2016 at different filtration velocities. The experimental findings show that the filtration efficiency increases with increasing velocity as the inertial impaction increases at higher velocity. The initial pressure differential shows an increasing relationship at Delta P-0 = 36.8 V-f(2) - 42.69 V-f + 28.92 with increasing velocity. The dust cake specific resistance coefficient, K-c increases linearly with the velocity at the depth filtration stage and the beginning of transitional filtration stage. K-c exhibits a quadratic growth with filtration velocity since the middle stage of transitional filtration and surface filtration. Dust holding capacity would be reduced and the final pressure differential would be increased with the increasing velocity due to the greater force incurred by the higher velocity, causing the filter media to deform and rupture easily. The experimental outcome of this study can be applied directly to industrial and commercial heating, ventilation and air conditioning design in consideration of the filter pressure differential for a lower energy consumption without compromising the efficiency for indoor air quality.