Influence of Twin-Scroll Turbocharging on the Performance of Direct Injection Gasoline Engine

In order to further understand the effect of twin-scroll turbocharging on the engine performance, this paper adopts a combination of one-dimensional numerical simulation and experimental research methods to compare the effects of two-scroll and single-scroll turbocharging on the power and fuel economy of direct injection gasoline engine. The research results show that, compared with the single-scroll turbocharger, twin-scroll turbocharger increased the low-end torque for 16% and 32% at 1000 r/min and 1500 r/min, respectively. However, the average fuel consumption has increased 1.3% at part load with twin-scroll turbocharger due to the pumping loss. Compared with a turbocharged port injection engine with a displacement 1.2 times that of the former, the twin-scroll turbocharged engine saved 11% fuel economy at part loads. The fuel consumption is saved 11% at part loads with twin-scroll turbocharger. This research first establishes the 1D simulation capability in twin-scroll turbocharger, and essentially researches the influence of twin-scroll turbocharger on GDI engine for the first time in China. Twin-scroll turbocharging can increase low-end torque of GDI engine efficiently, take advantage of pulse of exhaust manifolds, eliminate exhaust counter pressure of each cylinder, reduce the residual gas in cylinder so that the anti-knock capability is increased.