Accession Number : ADA019475

Title :   Flammability Study of Polymer Fuels Using Opposed-Jet Diffusion Flame Technique.

Descriptive Note : Technical rept.,


Personal Author(s) : Singhal,Surendra N. ; T'ien,James S.

Report Date : NOV 1975

Pagination or Media Count : 57

Abstract : Experiments emphasizying the extinction phenomena and the near-limit burning characteristics are performed on polymers, PMMA (Polymethylmethacrylate) and Delrin, using an Opposed-Jet Diffusion Flame apparatus. The measurements include burning rate and peak flame temperature and the variables are jet velocity and the oxidizer mole fraction. The measurements indicate the burning rate in the near-limit region departs from a power law relationship indicating the importance of finite rate chemical kinetics in this regime. Consistently, the peak flame temperature measurements prior to extinction show a sharp rate of decrease. Extinction does not occur on a sharp boundary in the oxygen mole fraction-jet velocity plane, but rather in a region (its size may depend on the experimental set-up and external disturbances) wherein extinction occurs in a random manner. The extinction statistics suggest that this is due to the quenching sensitivity of the near-limit flame to disturbances. Determination of chemical kinetic data using extinction 'boundary' is likely to have scatters due to the finiteness of the extinction region. It is suggested that matching of the burning rate curve in the near limit regime may give more reliable chemical kinetic data. (Author)

Descriptors :   *Fuels, *Flammability, *Polymers, Polymethyl methacrylate, Delrin, Kinetics, Extinguishing, Burning rate, Temperature, Oxidizers, Sensitivity, Jet propulsion, Nozzles, Lasers, Solid fuels, Velocity, Boundaries

Subject Categories : Fuels

Distribution Statement : APPROVED FOR PUBLIC RELEASE