INTERACTION OF JET DIFFUSION FLAMELETS WITH GRID-GENERATED CO-FLOW TURBULENCE

The flame front dynamics of a hydrogen jet diffusion flame interacting with co-flow grid-turbulence have been investigated using the laser induced Mie Scattering from Oil Droplets (MSOD) technique. The flame influence on the velocity field was also determined by two-component LDA. The experimental conditions were designed to minimize the generation of shear turbulence between the fuel and air flows. Both single point statistical data and tomographic high speed movies of MSOD were obtained. As shown by the tomographic movies, the flamelets are characterized by wrinkles comparable to the size of the turbulence integral scale. The probability density functions of the single point data show the intermittent nature of the flamelets. The velocity fluctuations, however. were not influenced by the flamelet fluctuation. The shear layer formed between the co-flow and room air is found to have influenced the flamelet dynamics and the velocity fluctuations at positions away from the jet exit. © 1991, Taylor & Francis Group, LLC. All rights reserved.