Numerical study of pleated fabric cartridges during pulse-jet cleaning

Abstract

We established a numerical model and used computational fluid dynamics (CFD) analysis to observe transient flow behavior across pleated filter cartridges in a dust collector during pulse-jet cleaning. The numerical results were in good agreement with the filter-testing data during important periods including during pressure ramp-up and valve opening. Larger errors for predicting overpressure occurred during the pressure ramp-down period likely due to the uniformity of the filters' permeability. This confirmed that the numerical model demonstrated the cleaning efficiency and the local cleaning quality of three different filter cartridges with different filter dimensions and pleat ratios. Data calculated from the average static pressure on the filters' surfaces were more closely correlated to cleaning efficiency than overpressure. The surface static pressure distribution along all filter cartridges showed that the top area of the filter cartridge is difficult to clean because of the lower surface pressure generated by the pulse jet. Filter cartridges with higher pleat ratios were found to have greater instances of incomplete cleaning due to the large variation of static pressure distribution along the filter cartridges. Our results showed that although information such as average pressure and pressure distribution on the filter surface is difficult to obtain by physical measurement, this data is tractable using CFD analysis and is useful for filter design and system optimization.