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A two-dimensional mesoscopic approach has been developed to investigate the flow and soot loading in the micro-channels of diesel particulate filter. Soot particle size examined is in the range of 10 nm to 10 μm. The flow is solved by an incompressible lattice Boltzmann model and the transport of solid particle is described in a Lagrangian frame of reference by cell automation probabilistic model. The lattice Boltzmann-cell automation probabilistic model (LB-CA model) is validated with the results of previous studies. The heterogeneous porous wall of DPF is generated by quartet structure generation set (QSGS). The effects of porous wall on the pressure field and velocity field are investigated. The distribution and deposition of soot particles with different sizes in clean channels are simulated. The dynamic evolution of solid boundary in soot particle capture process is investigated and the effects of the deposited soot particles on flow field are evaluated.

As the prime after-treatment device for diesel particulate matter (PM) emission control, Diesel Particulate Filter (DPF) has been widely used for its high particle capture efficiency. In order to study the particle motion and deposition distributions in the DPF inlet channel, a 2-D wall flow DPF microcosmic channel model is built in this paper. The motion trajectories of particles with different sizes are investigated considering the drag force, Brownian motion, gravity and Saffman lift. The effects of the space velocity on particle motion trajectories and deposition distributions inside the inlet channel are evaluated. These results demonstrate that the particle motion trajectories are highly dependent on particle sizes and influenced by the space velocity. The effect of the Brownian motion is obvious for fine particles and suppressed when the space velocity is raised.

Although diesel engines have higher output torque, lower fuel consumption, and lower HC pollutant emissions, larger amounts of NOx and PM are emitted, compared with equivalent gasoline engines. The diesel particulate filters (DPF) have proved one of the most promising aftertreatment technologies due to the more stringent particulate matters (PM) regulations. In this study, the computational fluid dynamics (CFD) model of DPF was built by utilizing AVL-Fire software code. The main objective of this paper was to investigate the pressure drop and soot regeneration characteristics of hexagonal and conventional square cell DPFs with various inlet mass flow rates, inlet temperatures, cell densities, soot loads and ash loads. Different cell geometry shapes of DPF were evaluated under various ash distribution types.

Although diesel engines offer higher thermal efficiency and lower fuel consumption, larger amounts of Particulate Matters (PM) are emitted in comparison with gasoline engines. The Diesel Particulate Filters (DPF) have proved one of the most promising technologies due to the “particle number” emissions regulations. In this study, the Computational Fluid Dynamics (CFD) multi-channel model of DPF was built properly by utilizing AVL-Fire software code to evaluate the pressure drop and soot accumulation characteristics of DPF. The main objective of this paper was to investigate the effects of soot (capacity and deposit forms) and ash (capacity and distribution factors) interaction on DPF pressure drop and soot accumulation, as well as the effects of DPF boundary conditions (inlet mass flow rate and inlet temperature) on pressure drop.

The main objective of this paper was to investigate the pressure drop characteristics of ACT (asymmetric cell technology) design filter with various inlet mass flow rates, soot loads and ash loads by utilizing 1-D computational Fluid Dynamics (CFD) method. The model was established by AVL Boost code. Different ratios of inlet to outlet channel width inside the DPF (Diesel Particulate Filter) were investigated to determine the optimal structure in practical applications, as well as the effect of soot and ash interaction on pressure loss. The results proved that pressure drop sensitivity of different inlet/outlet channel width ratios increases with the increased inlet mass flow rate and soot load. The pressure drop increases with the increased channel width ratio at the same mass flow rate. When there is little soot deposits inside DPF, the pressure drop increases with the bigger inlet.