STREAKED PARTICLE IMAGING VELOCIMETRY AND SIZING IN A SPRAY

Streaked particle imaging velocimetry and sizer (SPIVS), a nonintrusiv e system for planar instantaneous measurement of two-component droplet velocity and size in complex two-phase spray flows, is demonstrated. This system upgrades traditional double-light-pulse particle imaging t echniques by overlaying particle streakings on the particle image pair s. The advantages of this system are the enhanced reliability of the d roplet pairing process, the identification of the time sequence betwee n images of a droplet image pair, and the ability to measure the size of individual droplets. The resultant system can be applied to sprays with high droplet velocity gradients, droplets without preferred flow directions, and high droplet number density. The SPIVS system was demo nstrated on a GE SNECMA CFM56 engine combustor dual swirl-cup atomizer . The relative droplet size and velocity distribution of this spray fl ow are presented in this article.