Accession Number : ADA191565

Title :   Application of Rayleigh Scattering to Turbulent Flow with Heat Transfer and Combustion.

Descriptive Note : Final rept. 1 Apr 84-30 Sep 87,

Corporate Author : CALIFORNIA UNIV BERKELEY DEPT OF ENGINEERING

Personal Author(s) : Talbot, L

PDF Url : ADA191565

Report Date : 11 Dec 1987

Pagination or Media Count : 10

Abstract : A comprehensive investigation has been carried out of the structure and statistical properties of unconfined turbulent flames, both V-shaped and conical. Measurement techniques included conditioned velocity measurements using two component LDV, flow visualization techniques, and Rayleigh scattering. Additionally, a new time resolved technique, LARS(Linear Array for Rayleigh Scattering) was developed which makes possible the determination of the instantaneous location of the flame sheet within the turbulent flame brush. A major objective of these flame studies was to access the appropriateness of models such as the Bray-Moss-Libby (BLM) model for describing the structure of planar turbulent combustion zones. The results of these investigation have revealed that many of the predictions of the BML model accord reasonably well with experimental observations, although some of the constants chosen in the theory are not verified experimentally. Agreement is better for the V-shaped planar flame than for the conical flame, particularly in the vicinity of the flame tip. Studies of the flame stabilization region in the wake of flameholders showed evidence of vortex shedding in the wake and of diminished fluctuation intensity with increased heat release. It was also observed that reaction in the shear layer bounding the recirculating products does not occur until a finite distance downstream of the flameholder. This observation is confirmed by CH fluorescence imaging of the flame region.

Descriptors :   *COMBUSTION, *FLOW VISUALIZATION, *HEAT TRANSFER, *TURBULENCE, BOUNDARIES, BRUSHES, CONICAL BODIES, FLAME HOLDERS, FLAMES, FLUORESCENCE, HEAT, IMAGES, INTENSITY, LAYERS, MEASUREMENT, METHODOLOGY, PLANAR STRUCTURES, RANGE(DISTANCE), RAYLEIGH SCATTERING, REGIONS, RELEASE, SHEAR PROPERTIES, STABILIZATION, STATISTICS, TIME, TURBULENT FLOW, VARIATIONS, VELOCITY, VORTEX SHEDDING, WAKE

Subject Categories : Combustion and Ignition
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE