A numerical simulation method for pressure drop and normal air velocity of pleated filters during dust loading

Abstract

Pressure drop is an important indicator that affects the filtration performance of the pleated filter, and the deposition of dust particles within the pleats is crucial to the evolution of the pressure drop. In this study, the pressure drop during PM10 loading process was investigated for a series of V-shaped and U-shaped filters with a pleat height of 20 mm and different pleat ratios (the ratio of pleat height to pleat width: α = 0.71–3.57). In the numerical simulations, numerical models suitable for different pleated geometries were obtained through experimental verification on the local air velocity. Then, assuming that the dust cake thickness is proportional to the normal air velocity of the filters, the variation of the pressure drop with the dust deposition is derived by means of successive numerical simulations. This simulation method saved a significant amount of CPU time required for the growth of dust cake. It was found that the relative average deviations between experimental and simulated pressure drops were 3.12% and 1.19% for V-shaped and U-shaped filters, respectively. Furthermore, it was found that under the same pleat ratio and the mass of dust deposition per unit area, both the pressure drop and unevenness of normal air velocity of the U-shaped filter were lower than the V-shaped filter. Therefore, the U-shaped filter is recommended due to its better filtration performance.