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This work investigates the effect of a three-way catalytic converter and sampling dilution ratio on nano-scale exhaust particulate matter emissions from a gasoline direct-injection engine during cold-start and warm-up transients. Experimental results are presented from a four cylinder in-line, four stroke, wall-guided direct-injection, turbo-charged and inter-cooled 1.6 litre gasoline engine. A fast-response particulate spectrometer for exhaust nano-particle measurement up to 1000 nm was utilised. It was observed that the three-way catalytic converter had a significant effect on particle number density, reducing the total particle number by up to 65 % over the duration of the cold-start test. The greatest change in particle number density occurred for particles less than 23 nm diameter, with reductions of up to 95 % being observed, whilst the number density for particles above 50 nm diameter exhibited a significant increase.

This work investigates the effect of engine operating conditions and exhaust sampling conditions (i.e. dilution ratio) on engine-out, nano-scale, particulate matter emissions from a gasoline direct-injection engine during cold-start and warm-up transients. The engine used for this research was an in-line four cylinder, four stroke, wall-guided direct-injection, turbo-charged and inter-cooled 1.6 l gasoline engine. A fast-response particulate spectrometer for exhaust nano-particle measurement up to 1000 nm was utilized, along with a spark-plug mounted pressure transducer for combustion analysis. It was observed that the total particle count decreases during the cold-start transient, and has a distinct relationship with the engine body temperature. Tests have shown that the engine body temperature may be used as a control strategy for engine-out particulate emissions.

With increased numbers of vehicles on Irish roads, there is now a need to be able to scientifically assess the quantity of pollutant material to which populations are exposed. Traditionally, emissions have been determined using kinematic (vehicle speed) data but recent studies have identified that other parameters are of interest. The work in this Paper focuses on the development and testing of a purpose-built software system to extract on-board diagnostic data from a vehicle in order to derive a driving cycle and to use other engine characteristic data to better inform local pollutant and energy consumption models for Dublin. Comparisons with GPS data shows the system to be cost effective (price and computing overhead) and reliable.

Results are presented from a brief validation study on software which was written to simulate one-dimensional unsteady state transport of gaseous fuel mixtures through the intake manifold of a multi-cylinder, homogeneous charge spark ignition engine, and which also models in-cylinder thermodynamic and fluid flow processes, flame propagation, combustion and emissions formation. The focus of this paper is on the transport of pure hydrogen through the intake manifold of a 1.6 liter engine during the transition from steady state motoring to fired operation, at excess air ratios of 1.8 and 2.35. Indirect verification of hydrogen transport characteristics was determined by comparing measured and predicted IMEP's for different cylinders during the period immediately after hydrogen fuelling commenced.