Extended Model for Filtration in Gasoline Particulate Filters under Practical Driving Conditions

Abstract

In order to reliably predict the particle number filtration of gasoline particulate filters (GPF) under practical driving conditions, an extension to established filtration models is developed. For the validation of this approach and in order to close a gap of available measurement data at high space velocity in the literature, the particle-size-resolved fresh filtration efficiency of seven different cordierite filters is determined experimentally. Moreover, the experiments on a dynamic engine test bench focus on the impact of the pore-size distribution and the filter wall thickness under steady-state as well as transient, cold-start conditions. In order to model all trends observed, a new correlation for the particle collection due to inertial deposition is proposed and embedded in a heterogeneous multiscale model framework for a GPF. The presented approach can predict all trends observed in the measurements, including a stabilization of the filtration efficiency with increasing space velocities above a certain level. A comparison of several modeling approaches reveals the partly different behaviors at varying space velocities for the here presented model as well as for established filtration models.

Synergistic Effects of Multicomponents Produce Outstanding Soot Oxidation Activity in a Cs/Co/MnOx Catalyst

“…Particulate matter (PM, often called soot) emitted from diesel exhaust is one of the major environmental contaminants, which not only contributes to hazy weather but also causes severe public health problems such as bronchitis and lung cancers. − Thus, control of the emission of soot produced by diesel engines is an urgent and significant requirement for environmental protection and human health. The diesel particulate filter (DPF) is one of the most efficient solutions for soot control. , Yet, soot accumulates on the DPF, which needs periodic regeneration.…”

Modeling the Catalytic Performance of Coated Gasoline Particulate Filters under Various Operating Conditions

“…Especially for the relatively new cGPFs, there are still modeling approaches missing for the highly transient conditions encountered in automotive aftertreatment. Thus, we extended our previously published cGPF channel-scale model to simulate catalytic reactions. With the aim to capture all relevant transient phenomena, the applied reaction mechanism includes two different ceria sites and a time-dependent oxidation extent of the PGM centers.…”

“…In order to model the chemical behavior of a cGPF, we extend our previously published GPF model . A reactor model solves the governing equations for the conservation of energy, species, and momentum for one representative pair of an inlet and an outlet channel and the separating porous wall, as can be seen in Figure .…”

“…We develop a global reaction mechanism that can predict the steady-state light-off and high-load conversion in a broad λ-window and the behavior with a highly transient inlet feed. The kinetics are embedded in a previously published filtration model that is extended for this purpose …”

Applying 3D X-ray Microscopy to Model Coated Gasoline Particulate Filters under Practical Driving Conditions

“…For this purpose, Gong et al developed a workflow to incorporate the pore size distribution of low-resolved XRT scans in a previously developed macroscopic filtration model , for uncoated GPFs. This type of filtration model usually works on channel scale and has been an established approach for many years for diesel and gasoline particulate filters. − In a previous work of ours, we extended a macroscopic filtration model to high space velocities by suggesting a new correlation for the particle collection due to inertial deposition …”