A review of drop size measurement — the application of techniques to dense fuel sprays

The numerous experimental techniques that have been devised for measuring drop size distributions in sprays are reviewed. The techniques have been conveniently grouped into three categories for this purpose.

1. (i) Mechanical methods such as droplet capture, cascade impaction, frozen drop and wax methods and a sedimentation technique.

2. (ii) Electrically based methods comprising the Wicks-Dukler technique, the charged wire probe and the hot wire anemometer.

3. (iii) Optical methods consisting of photography, holography, laser diffraction, laser anemometry and various other techniques based on light scattering.

The limitations of each technique are identified in order to assess which are potentially useful in the high density sprays produced by large oil burner atomisers.