Examining Pleated Membrane Filter Performance Based on Pleat Packing Density and Cartridge Geometry
Student Presenter(s): Mikhail Smirnov
Faculty Mentor: Pejman Sanaei
Department: Mathematics
School/College: College of Arts and Sciences, New York City
Pleated membrane filters are widely used to remove undesired impurities from a fluid in many applications. A filter membrane is sandwiched between thick and porous support layers, then pleated and packed into an annular cylindrical cartridge with a central hollow duct for outflow. Although this arrangement offers a high ratio of surface filtration area to volume, the filter performance is not as efficient as those of equivalent flat filters. This stems from several possible hypotheses including the additional resistance due to the packing density of the pleats, the complex flow dynamics within the pleated membrane and possible damage of the membrane during the pleating process. In this work, we present an extension to a previous purely two dimensional model to investigate the effect of pressure variations along the axis of the filter cartridge in three dimensions. We also introduce a more sophisticated description of the cartridge geometry that accounts for the cylinder's curvature. Using asymptotic methods to simplify the flow throughout the cartridge makes it possible to investigate how the number of pleats or pleat packing density affects the performance of the pleated membrane filters, where the goal of this study is to find an optimal number of pleats to achieve a particular optimum filtration performance. Our findings establish the generality of the Goldilock's rule that neither too few nor too many pleats give optimum performance in a pleated filter cartridge.