Diesel Exhaust Particulate Characterization - Influence on DPF Filling Performance -

1. Diesel Exhaust Particulate Characterization- Influence on DPF Filling Performance - D. Foster, T. Root, T. Kawai, E. Wirojsakunchai, E. Schroeder, N. Schmidt, C. Kolodziej, R. Yapaulo Montajir et al. SAE 2005-01-0187 Merkel, G.A. et al • Objective:Diesel particulate filter (DPF) performance is influenced by a wide variety of parameters. Identifying the key variables is an area of ongoing research. A single cylinder Cummins N14 research engine, with a high pressure unit injector, was operated over a range of loads and speeds to gain understanding of fundamental mechanisms at work. • Lab Setup: Engine Operating Conditions Engine Out Particle Characteristics Soot particles display different filling behavior depending on size and chemical composition 3 Steady State Engine Operating Conditions are chosen to represent the various types of soot encountered in diesel exhaust Instrumentation Real-time PM mass & composition Real-time PM mass Particle size distribution Real-time particle size distribution Gas phase emissions PM mass & composition EC = Elemental Carbon (solid soot particles) OC = Organic Carbon (adsorbed hydrocarbons) DPF Specifications DPF Filling Performance (Pressure Drop) DPF Filling Performance (Filtration Efficiency) Mode 3,4 & 5, catalyzed Cordierite Significant soot breakthrough occurs during the first 900 s 4 3 2 Mode 3, Cordierite Mode 3, Cordierite Mode 3, SiC Magnitude of DPF pressure drop varies widely with substrate, engine mode and catalyst coating, Significant soot breakthrough occurs during the first 2000 s Filtration efficiency is poor until a soot cake begins to form Different DPF substrates, filter geometries and catalytic coatings are selected Mode 4, Cordierite Cordierite Substrate SiC Substrate