An experimental investigation of interaction of sprays with acoustic fields

This paper presents the effect of axial acoustic fields on an air-atomized spray. In these experiments, a spray of ethanol is established in a transparent test section in which an acoustic field is set up using acoustic drivers. Visual observation shows that a high-amplitude acoustic field (160 dB) reduces the length of the spray. The spray velocity field was characterized by particle image velocimetry (PIV) measurements. The spray velocities are considerably reduced in the presence of the acoustic oscillations, indicating the presence of smaller droplets. The presence of acoustic oscillations increases the spray cone angle. The flow field in the near field of the spray was characterized. There is considerable entrainment of air into the spray in the presence of acoustic oscillations. It is seen that the acoustic velocity rather than the acoustic pressure primarily affects the spray.