Measurement of Spatially Resolved Mean Velocities in a Transient Spray using Statistical Image Correlation Velocimetry

Statistical Image Correlation Velocimetry (SICV) was used to obtain mean velocity information in the spray issuing from a consumer fragrance injector. Statistical Image Correlation Velocimetry consists of obtaining several ensembles of the entire transient spray event at 1000 Hz. The spatial correlation coefficient between all the pixels in the image plane is then calculated from the ensemble of images. Based on the magnitude of the spatial correlation coefficient at different locations in the image plane, the mean velocity distribution is obtained. These velocities can be estimated from spatial correlation of streaklines in the images, without needing to resolve individual droplets. Furthermore, it is also not necessary to have well defined streaklines to estimate the velocity because the correlation is based on the statistics of the successive images, rather than on a single set of successive shots. The velocities obtained using SICV were compared with those obtained using a conventional Phase Doppler Anemometer (PDA). The mean velocities estimated from the fragrance dispenser compare reasonably well with those obtained using conventional PDA. * Corresponding author