2017 年 59 巻 187 号 p. 49-54
Gasoline vehicles, particularly, Gasoline Direct Injection (GDI) vehicles were subjected to regulations of PM (Particulate Matter) emissions because of the sales increase of GDI vehicles in the market. In this article, the emissions standards of PM for gasoline vehicles in Japan, EU and USA (EPA) are reviewed, and the latest regulatory trend are compared. The outline of PM generation in a GDI engine are explained as the fundamental information. In cold-fast-idle condition, for example, PM emissions in GDI engine originate from the wall fuel films produced by the fuel jet. The reported chemical compositions of exhaust PM are summarized. The major component is found to be Elemental Carbon (EC). Finally, the need for the modeling of PM generation is discussed for the numerical simulation in order to investigate the GDI engine with lower PM emission in the future.
