Velocity imaging for the liquid-gas interface in the near field of an atomizing spray: proof of concept

We describe adaptation of ballistic imaging for the liquid core of an atomizing spray. To describe unambiguously the forces that act to break apart the liquid core in a spray, one must directly measure the force vectors themselves. It would be invaluable, therefore, to obtain velocity and acceleration data at the liquid-gas interface. We employ double-image ballistic imaging to extract velocity information through the application of image analysis algorithms. This method is shown to be effective for liquid phase droplet features within the resolution limit of the imaging system. In light of these results, it is clear that a three- or four-image implementation of this technique would allow the determination of acceleration, and by extension, information about the forces active in spray breakup. (c) 2006 Optical Society of America.