Injector-Wall Interactions in Gas-Centered Swirl Coaxial Injectors
Abstract
Tailored injectors near the wall of a combustion chamber are often an integral part of a rocket engine's thermal management. However, most studies of injectors utilize single, isolated elements. The ability of walls to affect the expansion and stability of single-phase jets has already been well established. The effect of a wall on a multiphase flow, a spray, has not been established. Reported here is the impact a single wall has on the behavior of a spray from a single injector. Of specific interest are parameters which may impact engine performance, specifically attachment length, spray growth and stability. The atomizer being studied is a gas-centered swirl coaxial injector which relies on a dominant gas flow to drive the atomization. High-speed images are analyzed to assess the spray's behavior both qualitatively and quantitatively. Three wall offset ratios, 0.57, 0.83 and 1.16, are compared to the free spray. Sprays are qualitatively similar, but the wall has a quantitative effect on spreading rate. The wall is able to decrease the variability in the spray, but not globally-only very near the wall.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 05, 2011
- Accession Number
- ADA554932
Entities
People
- B. Eilers
- M. D. Lightfoot
- Stephen A. Danczyk
- Stephen Alexander Schumaker
- V. Narayanan
Organizations
- Air Force Research Laboratory