Numerical Investigation of Axial Velocity Uniformity in Porous Medium of Gasoline Particulate Filters

In order to meet new real-world emissions standards and reduce particulates emitted by GDI engines, automakers are increasingly adopting gasoline particulate filters (GPFs). The uniformity of axial permeation velocity through porous medium in GPFs significantly impacts filtration efficiency. Consequently, a three-dimensional single-channel GPF–CFD model is developed to investigate the impact of partition coatings and pins on flow characteristics. Different coating amounts are compared by adjusting porosity using a single-channel GPF model, with pins strategically placed along the upper and lower sides of the inlet channel. Simulation results indicate that optimizing porosity and length across different coated sections enhances the consistency of axial permeation velocity, particularly when the ratio of coated length falls within the range of 30–40%. Pins reduce the axial variance by increasing permeation velocity near the inlet surface, with a symmetrical arrangement of four pairs and a height of 0.3 mm yielding optimal performance. Moreover, the combination of partitions and pins shows potential to improve maximum homogeneity by approximately 75%.