Measurement of Transient PM Emissions in Diesel Engine

Transient emission peaks have become an important fraction of the total emissions during the standardized test cycles for passenger car Diesel engines. To this end this paper is concerned with the challenge of measuring emissions during transients. The importance of this topic is increasing due to strict regulation on pollutant emissions. Hence, suitably accurate and fast measurement devices for PM emission detection are required. Thus, we present a comparison between different measurement techniques for Particulate matter (PM) emissions from a Diesel engine, in particular during transients. The compared equipments include AVL Micro soot sensor, AVL Opacimeter, Differential mobility spectrometer and Laser induced incandescence. The goal of this paper is to reveal the most accurate device in the sense of sensitivity and dynamics for fast measurements of PM from a Diesel engine. The main subject of the studies was to quantify the difference in transient performance of the devices at several measurement positions during standardized emission test cycles. The measurement devices were placed into various locations in the exhaust of a Euro 5 passenger car Diesel engine, namely in the upstream of the turbine, in the downstream of the turbine and in the tailpipe. The analyses present the benefits and disadvantages of measuring close to the actual combustion event. The obtained results will allow better understanding PM emissions and support dynamic emission modelling as well as control design.