Visualization of Concentration Field in a Vortex Ring Using Acetone PLIF

Article type: Research Article

Authors: Choi, H.J. | Ko, Y.S. | Chung, S.H.

Affiliations: School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea. | Korea Aerospace Research Institute, Yusung P.O. Box 113, Daejon 305-600, Korea.

Abstract: To improve the understanding of flame propagation through a nonpremixed vortex ring, the characteristics of fuel concentration in a vortex ring have been investigated experimentally. The vortex ring was generated by the ejection of propane with a single stroke motion of a speaker. Planar laser-induced fluorescence (PLIF) technique was adopted by seeding acetone as a tracer to fuel stream, in which the PLIF signal intensity is directly proportional to the concentration of acetone. This technique provides non-intrusive and instantaneous measurement of concentration field. Results showed that fuel concentration and its gradient decreased with the evolution of a vortex ring. When a nonpremixed flame propagated through a vortex ring, the flame location coincides with the inner most spiral mixing layer of fuel and air in a vortex ring.

Keywords: vortex ring, acetone PLIF, nonpremixed flame, flame propagation

Journal: Journal of Visualization, vol. 5, no. 2, pp. 145-152, 2002