Towards Controlled Liquid Atomization

The present study discuss controlling mechanisms of air-blast atomization and the prospect of external triggering for enhancing atomization quality of a planar liquid sheet. The investigation builds on previous experimental evidence provided by flow visualization of 2-D liquid sheets formed between two co-flowing air streams at variable velocities, and is particularly aimed to improve our understanding on air-blast atomization for lean combustion and low-emission engines. The study is extended by varying the sheet thickness and through the detailed analysis of physical processes occurring at the liquid-gas interface, namely the liquid surface wave growth characteristics due to viscous shear. The results show that the influence of waves on liquid sheet break-up is confined only to a thin region near the interface, and thus require properly tuned, and externally-controlled, excitations for effective atomization.