Random pore structure and REV scale flow analysis of engine particulate filter based on LBM

Abstract

In this article, lattice Boltzmann method (LBM) is used to simulate the multi-scale flow characteristics of the engine particulate filter at the pore scale and the representative elementary volume (REV) scale, respectively. Four kinds of random wall-pore structures are considered, which are circular random structure, square random structure, isotropic quartet structure generation set (QSGS), and anisotropic QSGS, with difference analysis done. In terms of the REV scale, the influence of different inlet flow velocities and wall permeabilities on the flow in single channel is analyzed. The result indicates that the internal seepage laws of random structures constructed in this article and single channel are in accordance with Darcy’s law. Circular random structure has better permeability than square random structure. Isotropic QSGS has better fluidity than anisotropic one. The flow in single channel is similar to Poiseuille flow. The flow lines in the channel are complicated and a large number of vortices appear at the ends of channel with high inlet flow rate. With the increase of inlet velocity, the static pressure in channel gradually increases along the axial direction as well as the seepage velocity. The temperature field in the channel becomes more uniform as the flow velocity increases, and the higher temperature distribution appears on the wall of the porous media.

Lattice Boltzmann Modelling of Fluid Flow through Porous Media: A Comparison between Pore-Structure and Representative Elementary Volume Methods

“…As shown, the distribution of irregular structures and larger pores enables the fluid flow with relatively better permeability. Conversely, the solid in-line s causes a higher pressure drop and lower permeability than other arrangement case of the lowest porosity factor [42], the pressure drop in the in-line geometry w than double compared to the random arrangement, so a regular and uniform po ture can cause higher fluid flow resistance than the staggered and random configu…”

“…causes a higher pressure drop and lower permeability than other arrangements. In case of the lowest porosity factor [42], the pressure drop in the in-line geometry was m than double compared to the random arrangement, so a regular and uniform pore str ture can cause higher fluid flow resistance than the staggered and random configuratio…”