Search Results

The aim of this work is to analyze particle number and size distribution from a small displacement Euro 5 common rail automotive diesel engine, equipped with a close coupled aftertreatment system, featuring a DOC and a DPF integrated in a single canning. In particular the effects of different combustion processes on PM characteristics were investigated, by comparing measurements made both under normal operating condition and under DPF regeneration mode. Exhaust gas was sampled at engine outlet, at DOC outlet and at DPF outlet, in order to fully characterize PM emissions through the whole exhaust line. After a two stage dilution system, sampled gas was analyzed by means of a TSI 3080 SMPS, in the range from 6 to 240 nm. Particle number and size distribution were evaluated at part load operating conditions, representative of urban driving.

Experimental work was carried out on a small displacement Euro 5 automotive diesel engine alternatively fuelled with ultra low sulphur diesel (ULSD) and with two blends (30% vol.) of ULSD and of two different fatty acid methyl esters (FAME) obtained from both rapeseed methyl ester (RME) and jatropha methyl ester (JME) in order to evaluate the effects of different fuel compositions on particle number (PN) emissions. Particulate matter (PM) emissions for each fuel were characterized in terms of number and mass size distributions by means of two stage dilutions system coupled with a scanning mobility particle sizer (SMPS). Measurements were performed at three different sampling points along the exhaust system: at engine-out, downstream of the diesel oxidation catalyst (DOC) and downstream of the diesel particulate filter (DPF). Thus, it was possible to evaluate both the effects of combustion and after-treatment efficiencies on each of the tested fuels.

Particulate Matter (PM) particles number and size distribution emitted from a small displacement automotive Common-Rail Diesel engine were analyzed in order to evaluate the impact of different engine operating parameters, such as engine load, EGR rate and injection pattern during DPF regeneration. The engine was equipped with a close coupled aftertreatment system, featuring a Diesel Oxidation Catalyst (DOC) and a Diesel Particulate Filter (DPF) integrated in a single canning. The pollutant emissions were sampled at two locations along the exhaust system: at the engine outlet and downstream of the diesel oxidation catalyst, in order to characterize particles entering the DOC and the DPF respectively. Particle size distributions were measured by means of a two stage dilution system coupled with a downstream Scanning Mobility Particle Sizer (SMPS).