Example data
The following pictures contain some data measured with DMM:
Reproducibility
European Transient Cycle (ETC), repeated 8 times. Heavy-duty bus engine, PM emission was below EURO 4 regulations. Sampling was done using 2 ejector diluters, the first one was heated; dilution ratio was about 1:80, not taken into account in the picture. Average measured concentrations over the cycles were 22.95 ug/m3, standard deviation 1.73 ug/m3, that is, approximately 7.5%.
Sensitivity
Citroen C5 HDI, an LD diesel vehicle equipped with a DPF. Measured from the tailpipe, dilution ratio about 1:80, not taken into account.
A DPF was loaded by driving a long period with constant speeds until at 12:26 the engine load was increased to maximum torque. Exhaust temperature was increasing until 12:42 when the DPF started regeneration.
The detection limit was about 1 ug /m3 and concentration during regeneration was about 3 times higher than during normal operations.
Mass correlation
Various light- and heavy duty engines were measured using different dilution systems and dilution ratios. As seen in the following picture the accuracy is excellent and the dynamic range is very wide.
