EXPERIMENTAL-STUDY OF SPACE AND TIME-RESOLVED STRUCTURES OF TURBULENT-DIFFUSION FLAME

The authors discuss in detail the various beat transportation mechanis ms existing in turbulent diffusion flames by use of spectral analyses. Space and time-resolved structures of turbulent diffusion flames were analyzed by two-point laser Rayleigh spectroscopy (LRS) which did not directly interfere with the combustion media during measurement. The turbulent diffusion flame structures were divided into 4 regions based on the characteristics of their spectral analysis of time-dependent t emperature signals. In order to discuss the macroscopic heat transport ation mechanism, the coherent function from cross and power spectral f unctions at Region I similar to IV was analyzed. From these analyses: the following diffusion characteristics at each region were revealed. Region I : three-dimensional diffusion mechanism (x-, r-, z-axes), Reg ion II: one-dimensional diffusion mechanism (z-axis), Region III: two- dimensional diffusion mechanism (x-, z-axes), Region IV: no specific d iffusion mechanism.