Multiple injection strategies for improved combustion stability under stratified part load conditions in a Spray Guided Gasoline Direct Injection (SGDI) engine

Abstract

Compared to conventional homogeneous direct injection or port-fuel injected engines, the second generation, spray guided, direct injection engine (SGDI) has the potential for significantly improved fuel economy during part load stratified charge operation. Multiple fuel injection strategies can be utilised to increase the unthrottled operating range, leading to further improvements in fuel economy. However, careful optimisation of these strategies is essential to ensure that benefits are maintained whilst further minimising emissions within combustion stability limits and consumer driveability demands.