Numerical and experimental investigations of the early injection process of Spray G in a constant volume chamber and an optically accessible DISI engine

In this work, the Engine Combustion Network Spray G injector was mounted in Darmstadt optical-accessible engine to study phenomena typical of multi-hole, early direct-injection events spark-ignition engines characterized by tumble flow charge motion. Dedicated experimental measurements both in-cylinder spray morphology and velocities before after injection process were carried out assess adopted numerical setup under real conditions. A dynamic secondary breakup model from literature coupled with an atomization multi-motion regime model. The validated against state-of-the-art ECN experiments for a constant-volume chamber low evaporating condition. Then, simulation achieved results compared data. Overall, good agreement between simulations observed velocity fields cases. With reference calculations intake seen induce asymmetry. partial vortex generated during phase on plane interacts spray, developing into full which induces upward that stabilizes spray. flows below valve increase dilution plume outside plane, therefore exhibits reduced penetration. Moreover, valves protect energetic recirculation at tip plumes lie plane. helps fuse vapor fuel clouds individual near tip, obtaining shape like horseshoe multi-hole injector. Finally, phenomenological interaction jets introduced describe evolution DISI engine.