Imaging in the Optically Dense Regions of a Spray: A Review of Developing Techniques
Review article, 2013
Since the year 2000, a number of very different techniques to image spray formation in optically dense
regions of atomizing sprays have appeared in the literature, been further developed, and applied to
sprays. Three of them are transillumination techniques (meaning a beam is passed all the way through
the spray and imaged on the other side, often called ‘line-of-sight’), one technique is internally illuminated
(the signal originates inside the spray), and one is a planar laser imaging technique. Researchers
intending to use these new results need to understand with clarity what exactly the measurements
provide and how reliably they can provide them. This article intends, therefore, to bring some order to
the discussion of techniques. It includes a description of each of the five techniques, a review of advantages
and limitations for each of them, a comparison, and a discussion of future trends. Most of the
techniques are certain to evolve and improve further, but this article can provide a snapshot in time and
help create a context for understanding.
Dense regions
Spray formation
Imaging