Sampling and Engine After-Treatment Effect On Diesel Exhaust Particle Size Distributions

Sampling and engine after-treatment effect on diesel exhaust particle size distributions is studied by reviewing measurement data from a heavy-duty diesel engine and from a diesel aggregate. Measured data was evaluated for nucleation effects on particle size distributions. Transformation of size distributions through coagulation is calculated in standard diesel sampling systems and in the Fine Particle Sampler (FPS). In addition, stability of the CVS-based standard sampling systems and the FPS system is discussed. The results indicate that standard sampling systems are applicable to number and size distribution studies only in specific conditions. An FPS system is introduced to fulfill the required characteristics for a sampling device to be used with low and high particle concentrations. Also, the stability and possibility to adjust dilution ratios and temperatures makes FPS applicable for accumulation and nucleation particle studies.