Effect of atomizing air flow on spray atomization of aninternal-mix twin-fluid atomizer

• Main Authors: Chong, Cheng Tung, Hochgreb, Simone
• Format: Article
• Published: Begell House Inc. 2015
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://eprints.utm.my/id/eprint/58351/; http://dx.doi.org/10.1615/AtomizSpr.2015011361

The effect of the atomization air flow rate on the spray characteristics of a swirling twin-fluid atomizer operating on Diesel fuel is investigated. The mean droplet axial velocity and size distributions were simultaneously measured using a phase Doppler anemometer (PDA). The mean droplet diameter is found to increase with radial distance from the spray centreline, while its axial velocity decreases from a peak at the centreline. Increasing the atomizing air-liquid fuel mass ratio (ALR) reduces the fuel droplet size due to the increased shear and increases the spray penetration length as a result of increased momentum. Comparison of the drop size-ALR relations to previous independently developed correlations shows good agreement. A comparison was made between the observable boundaries obtained with Mie scattering and the droplet number density. It is found that the Mie images correspond to 95%-99% edge of the cumulative droplet mass distribution through the spray.