Starting from September 2011 a limit of 6×1011 #/km was introduced for the type approval of diesel passenger cars that will eventually apply to all new registered diesel passenger cars from September 2012. The same limit will also apply to diesel light duty vehicles but with a one year delay (09/2014 for type approvals and 09/2015 for all new registered vehicles). The regulation states that a Particle Number (PN) limit will also be introduced for the certification of Euro 6 technology gasoline-fuelled vehicles but the threshold value was not decided yet. While conventional Port Fuel Injection (PFI) gasoline vehicles can easily comply with the diesel limit, their Direct Injection (G-DI) counterparts are found to emit systematically above this threshold by up to 1 ½ orders of magnitude. It is therefore expected that application of the diesel particle number limit to G-DI vehicles may necessitate the installation of a particulate filter.At the same time, the penetration of G-DI vehicles is expected to rapidly grow in the near future in both the European and USA markets. This is due to their improved fuel efficiency compared to the conventional PFIs, that would potentially enable the target set in both EU and USA on the fleet-average carbon dioxide (CO2) emissions of future vehicles. It is foreseen that this vehicle category will dominate the gasoline market eventually replacing the conventional and less efficient PFI vehicles. There are concerns however, that their elevated particulate emissions may adversely affect the air quality in the future if no measure is taken to efficiently control them.In this direction the present study examined the feasibility of introducing Gasoline Particulate Filters in G-DI vehicles and investigated the associated implementation cost and environmental benefit.
展开▼
