Experimental and computational approach to the transient behaviour of wall-flow diesel particulate filters

• Published in: Energy (Oxford) 2017-01, Vol.119, p.887-900
• Main Authors: Torregrosa, Antonio José, Serrano, José Ramón, Piqueras, Pedro, García-Afonso, Óscar
• Format: Article
• Language: English
• Subjects: Acoustics; Aftertreatment; Air pollution; Automotive emission standards; Computer applications; Damping; Design criteria; Devices; Diesel; Diesel engines; Diesel particulate filter; Dissipation; Emission standards; Filters; Fluid dynamics; Fluid filters; Frequency domain analysis; Honeycomb construction; Nonlinear response; Particulates; Pollutants; Pollution abatement; Substrates; Unsteady flow; Vehicle emissions
• ISSN: 0360-5442; 1873-6785
• DOI: 10.1016/j.energy.2016.11.051

The implementation of tight vehicle emission standards has forced manufactures to use aftertreatment systems extensively. In addition to pollutant emissions abatement, these devices have a noticeable impact on the wave pattern. This fact affects the muffler design criteria. All monolithic aftertreatment devices produces a damping effect because of the honeycomb structure and the narrow channels. However, this response is more marked in wall-flow diesel particulate filters (DPF) because of the alternatively plugged ends and the dissipative properties of the porous substrate. The main goal of this paper is to assess the transient fluid-dynamic behaviour of wall-flow DPFs using experimental and modelling techniques. The experimental data were gathered in clean and loaded conditions. The DPF was subjected to a variety of pressure excitations to characterise its transient behaviour in the time and frequency domains. Afterwards, the DPF response was evaluated under engine-like operating conditions in an unsteady flow gas stand. Once the main characteristics of the response were known, a non-linear gas-dynamics model was proposed for analysis and prediction. The model accounts for space and time gradients, combining the thermo-and fluid-dynamic solution with a model based on a packed bed of spherical particles that defines the meso-structure of the loaded substrate. •Analysis of transient behaviour of wall-flow diesel particulate filters.•Experimental and computation approach.•Amplitude of flow pulses and DPF soot loading influence on the wave pattern.•Hypothesis of porous substrate as homogeneous medium essentially valid.•Soot deposits effects on the reactive response.