Characterisation of diesel exhaust particle number and size distributions using mini-dilution tunnel and ejector–diluter measurement techniques

This paper presents the characteristics of diesel exhaust particle number and size distributions. These were measured for different engine load conditions from 10% to 100% of full engine load at a maximum torque of constant speed, using mini-dilution tunnel and sampling (MDTS) and ejector–diluter and sampling (EDS) systems. The exhaust particles sampled were analysed using a scanning mobility particle sizer (SMPS). In general, the particle number concentration increased with increasing engine load using both measurement systems. Comparing the particle number and volume concentrations, the MDTS system measures a lower level in the nanoparticle range, Dp<50 nm, but a higher level in the accumulation mode size range, 50