Accession Number : AD0763340

Title :   A Weakly Turbulent Flame with High Activation Energy,

Corporate Author : PURDUE UNIV LAFAYETTE IND PROJECT SQUID HEADQUARTERS

Personal Author(s) : Williams,Forman A.

Report Date : JUL 1973

Pagination or Media Count : 54

Abstract : A previously outlined approach to turbulent flame theory is extended to premixed combustibles with high activation energy. Emphasis is placed primarily on turbulence whose integral scale is large compared with the thickness of the laminar flame. Only the limit of low intensity for the turbulence is considered. The two-zone structure of the turbulent flame parallels that of a laminar flame. In the diffusion zone, velocity fluctuations act on the mean concentration gradient to generate concentration fluctuations, which persist in the reaction zone to perturb the profile of mean concentration there. This turbulent modification to the mean reaction-zone structure produces a turbulent correction to the flame speed, which is calculated. It was found that an increase in the ratio of the rms velocity fluctuation to the laminar flame speed, an increase in the ratio of the turbulence macroscale to the laminar flame thickness, or an increase in the ratio of the activation temperature to the flame temperature, generally will cause an increase in the ratio of the turbulent flame speed to the laminar flame speed. (Modified author abstract)

Descriptors :   (*FLAMES, *HEAT OF ACTIVATION), TURBULENCE, DIFFUSION, NUMERICAL ANALYSIS

Subject Categories : Combustion and Ignition

Distribution Statement : APPROVED FOR PUBLIC RELEASE