A pleated membrane filter consists of a porous membrane layer, which is surrounded by two supporting layers, and the whole structure is pleated and placed into a cylindrical cartridge. Pleated membrane filters are used in a variety of industrial applications, since they offer more surface area to volume ratio that is not found in equivalent flat filters. In this work, we introduce a novel three-dimensional model of a pleated membrane filter that consists of an empty region, a pleated region, and a hollow region. The advection diffusion equation is used to model contaminant concentration in the membrane pores along with Darcy's law to model the flow within the membrane and support layers, while the Stokes equation is used for the flow in the empty region and the hollow region. We further use the key assumptions of our model based on small aspect ratios of the filter cartridge and the pleated membrane to simplify the governing equations, which can be easily solved by numerical methods. By performing these steps, we seek to discover an optimal pleat packing density to find the optimum filter performance, while not exceeding a threshold for the particle concentration at the filter outlet.
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Modeling the Flow and Transport Dynamics in Gasoline Particulate Filters to Improve Filtration Efficiency
We propose a new pore-scale/channel model, or hybrid model, for the fluid flow and particulate transport in gasoline particulate filters (GPFs). GPFs are emission control devices aimed at removing particulate out of the exhaust system of a gasoline direct injection engine. In this study, we consider a wall-flow uncoated GPF, which is made of a bundle of inlet and outlet channels separated by porous walls. The particulate-filled exhaust gas flows into the inlet channels, and passes through the porous walls before exiting out of the outlet channels. We model the flow inside the inlet and outlet channels using the incompressible Navier–Stokes equation coupled with the spatially averaged Navier–Stokes equation for the flow inside the porous walls. For the particulate transport, the coupled advection and spatially averaged advection–reaction equations are used, where the reaction term models the particulate accumulation. Using OpenFOAM, we numerically solve the flow and the transport equations and show that the concentration of deposited particles is nonuniformly distributed along the filter length, with an increase of concentration at the back end of the filter as Reynolds number increases. Images from X-ray computed tomography (XCT)-scanning experiments of the soot-loaded filter show that such a nonuniform distribution is consistent with the prediction obtained from the model. Finally, we show how the proposed model can be employed to optimize the filter design to improve filtration efficiency.
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- Award ID(s):
- 1839050
- NSF-PAR ID:
- 10166560
- Date Published:
- Journal Name:
- Journal of dynamic systems measurement and control
- ISSN:
- 0022-0434
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4046151
