A Study of Injector Matching on a High Thermal Efficiency TGDI Gasoline Engine

By using a visual single-cylinder transparent engine and thermodynamics test bench, this paper aims to research the suitable injector for a high thermal efficiency (BTE 42%) TGDI gasoline engine. It focuses on the matching with a high tumble ratio combustion chamber with different spray angle, spray target position, as well as the influence on the characteristics of in-cylinder flow, combustion and emissions, to find the suitable injector for a high tumble ratio of the combustion chamber. The test results show that a 5-hole injector has the best matching with the combustion chamber and in-cylinder flow, which can effectively reduce the risk of spray impact piston head and cylinder wall. Combined with the multiple injection strategy, higher power, torque and lower part-load fuel consumption are achieved, as well as optimal emissions.