Nanoparticle Counts Emissions of Trucks: EURO 3 with and without DPF Compared to EURO 4 and EURO 5

Investigations of emissions from three modern HD vehicles (HDV) were carried out on a chassis-dynamometer. One of the vehicles uses PM-Kat and is certified according to EURO4. The second one is EURO5 compliant and uses SCR. The third one is was a EURO3 HDV, which was tested with and without VERT-certified DPF. The investigation focussed on solid particles in the mobility size range of 10-400nm. The instruments were SMPS, NanoMet, PASS and ELPI. Sampling conformed to PMP for SMPS and NanoMet, PASS and ELPI were used with FPS-dilution. Metallic emissions were measured using ICP-MS. Also measured were inherent secondary emissions, especially NO2 and NH3. Compared to EURO3 without DPF a moderate curtailment of nanoparticle emissions was observed for the majority of operating points for EURO4 with PM-Kat and EURO5 with SCR. However, at full load the EURO5 engine emitted higher concentrations than a EURO3 engine without DPF. A stochastic particle release was observed from the PM-Kat of the EURO4 engine. Its penetration scatter was very much dependant on the soot burden and the testing history. Compared to a EURO3 engine with a DPF conforming to VERT criteria, both modern engines EURO4 and EURO5 emitted 100-500 times more nanoparticles. Very good results of the gaseous emissions – a significant reduction of NOx – showed the EURO5 engine. There were no deleterious effects observed due to the SCR. The concentrations of NH3 and N2O remained close to the detection limit. However, the EURO4 engine emitted rather high concentrations of NO2 at about half load range. Emissions of Vanadium with EURO5 and Platinum with EURO4 were low in both cases, even below detection limit.