Effect of Swirl on Gas-Centered Swirl-Coaxial Injectors Propulsion Systems
Abstract
Physics-based scaling laws and design methodologies for gas-centered swirl-coaxial injectors have been under consideration for several years. Prior work showed that scaling via a momentum flux ratio was promising. However, that work neglected the effects of liquid swirl on the atomization. This current work refines the definition of the momentum flux ratio by adding compressibility in the gas phase and using a total liquid velocity. The focus, however, is on the impact of swirl through the study of different liquid inlet configurations. The film length and character are studied for a range of swirl values with ratios of axial to total velocity ranging from 26 to 41 percent. The new definition of momentum flux ratio collapses film length data onto a single curve over the range of swirl levels and interior injector geometries. The character of the film is seen to change, particularly in regards to gas entrainment into the film, as the swirl is decreased. Changes in swirl have little impact on film length; this is anticipated because the centripetal forces are several orders of magnitude lower than the aerodynamic forces driving atomization. Some examination of an inlet with no swirl (axial to total velocity ratio of 100 percent) is also presented.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 13, 2011
- Accession Number
- ADA548598
Entities
People
- Malissa D. Lightfoot
- Stephen A. Danczyk
- Stephen Alexander Schumaker
Organizations
- Air Force Research Laboratory