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The European Programme on EMISSIONS, FUELS and ENGINE TECHNOLOGIES (EPEFE) was conceived to investigate the impact on emissions of changing fuel composition for the use in future engines/vehicles meeting at least the 1996 European Emission Limits. Participating members of the European car constructors association, ACEA provided the largest vehicle/engine fleet ever tested in an European emissions programme. The most important criteria was to provide vehicles which would span the emission range within the new EC limits to ensure that representative emissions of the future car parc are provided for use in the Auto Oil Air Quality model. In this paper the broad range of 16 gasoline- and 19 diesel vehicles as well as five heavy duty engines their technology and their exhaust emission control devices are introduced and discussed.

Within EPEFE the relationship between exhaust emissions of five 1996 heavy duty engines including advanced technologies and an eleven diesel fuel matrix has been investigated. The fuel matrix was designed to study the effects of decorrelated fuel properties (density, polyaromatics, cetane number, back-end volatility (T95)). The main programme consisted of engine testing on the 88/77 EEC test cycle at standard engine settings. The findings were quantified using regression equations and showed, that fuel effects varied in both magnitude and direction between the four emission components. Individual engines had different emission levels and responded differently to fuel properties, due to engine technology. Additional tests were conducted with selected fuels at adjusted engine settings and timing. The observed density effect on emissions can be compensated for and fully explained by physical interactions with the injection system.

From september 1988 a fleet test started in Italy on urban buses equipped with a single ceramic monolith filter plus a by-pass and Diesel fuel burners for regeneration. The operation of the particulate trap, during the normal bus running in the city, has been assessed in three different ways: 1. Continuous control, by means of a data acquisition system purposely designed, of the main parameters affecting regeneration (i.e. time between consecutive regenerations, temperature in three selected zones in the filter during regeneration,filter loading); 2. Periodic control of smoke opacity of the bus measured, with and without the filter, under free acceleration and when bus is accelerating from 50 to 65 km/h on proving ground; 3. Particulate collection efficiency of the trap by using a dilution tunnel with the engine operated at the test bench. Information carried out from the fleet tests and additional information deriving from laboratory results were used for the system improvement.

Engine design changes contemplated to meet the 1991 particulate legislation have broken away from the evolutionary changes which have led us to todays' engine designs. The impact of these design changes on lubricants are far ranging and include those resulting from differences in crownland clearances, ring location, piston style, injection pressures, and virtually every design application contemplated by the engine builder. This paper attempts to quantify present design practice, and based on limited data, speculate on problems which might arise as a result of particulate control. Special concern is raised regarding the need for lubricant sup-lier/additive manufacturer and engine designer interaction to prevent a situation from occurring where 1991 engines are introduced which do not have proper lubricants waiting for them.