Comparative Study of Biodiesel and Diesel Jets in Gaseous Crossflow

This study compares the fundamental spray characteristics, such as penetration depth, droplet diameter, velocity, and volume flux of, biodiesel and diesel as well as their blends. Liquid jet is injected into an air crossflow with a speed of 58 m/s. A series of experimental tests covering Weber numbers from 29-82, and momentum flux ratios from 10-133, are conducted using the shadowgraph method and phase Doppler particle analyzer. The shadowgraph images are processed to find the penetration depth and to investigate different regimes of breakup. The phase Doppler particle analyzer is used to capture droplet size distribution, velocity, and volume flux. The results differ remarkably in terms of breakup regimes and trajectory for biodiesel blends, which may be due to the high viscosity of biodiesel in comparison to diesel. For example, at a Weber number of 80, some bag breakups are observed on the biodiesel jet against the expectation that, at this Weber number, most of the liquids experience atomization mode.