HC Emission Analysis of Gasoline Direct Injection Engines and Challenge Faced by Such Engines in Meeting Future's Emission Standard

Based on the introduction of the basic combustion concept of gasoline direct injection(GDI) engine and its operation under different operating conditions, HC emission mechanisms of the GDI engine are analyzed. And HC emission characteristics of the GDI engine are compared with the PFI engine via a comparison test based on the FTP 75 driving cycle. It can be concluded that the GDI engine is facing a big challenge in meeting the future's HC emission standard. Reasons for the higher HC emissions of the GDI engine are discussed and the ways for HC emission control are given.