ID 51

An Experimental Investigation on the Effect of Split Injection on Spray-Vortex Interaction of SIDI engine using High-Speed PIV

 

Abstract:

Split injection has been proved to be an effective way to accelerate mixture formation, reduce emissions and increase the power output of SIDI engine. Meanwhile, wall-guided (WG) design is widely used in SIDI (Spark ignition direct injection) engines due to its relative low cost and simplicity particularly when updating an existing PFI (Port Fuel Injection) engine to a SIDI engine. However, there is a lack of systematic investigation on the correlation between split injection with pressure-swirl nozzle, which is adopted in WG design SIDI engines. Difficulties to optimize split-injection strategies, especially the specific injection timing and the dwell width appear to be a major problem when many different injection permutations are available. In this study, the effect of dwell width on a pressure-swirl nozzle under various ambient pressures and temperatures was investigated using a high-speed particle image velocimetry (PIV) system. The influence of split injection strategies and ambient pressure/temperature on the spray geometry, flow field and spray-vortex interaction were fully revealed. These results are imperative for understanding the spray-vortex interaction and of practical value for modeling split-injection spray engines.