Numerical simulation of diesel particulate filter flow characteristics optimization: From the perspective of pore structure parameters and inlet velocity

The diesel particulate filter (DPF) with porous media structure has become an essential component for diesel engines to satisfy increasingly strict emission standards. This study constructed a porous media structure model of DPF, and optimized its boundary to conduct a simulation on the flow characteristic with different influencing parameters using the lattice Boltzmann method (LBM). Results showed that the increase of the average flow velocity of the DPF model reduced the pressure drop, indicating that the flow probability of model improved. In addition, the porosity application range was expanded. The visualization and quantization of the velocity and pressure distribution with the DPF revealed that an increase of the wall thickness resulted in a higher pressure drop of the DPF, but a lower flow velocity. Further, the fractal dimension of the porous media exhibited no direct relationship with the DPF pressure and velocity performance; however, the outlet velocity and pressure drop of the model were optimized within the different porosity. Moreover, both the increase in the spectral dimension and model optimization improved the DPF permeability. The impact of increasing the inlet velocity on the pressure drop was particularly significant as it accelerated the rate of pressure drop, illustrating that a smoother porous media boundary was conducive to improve the flow performance of DPF, which facilitated a better scheme for the design of DPF porous media.