PLIF Imaging of Species and Temperature Distributions in Spray Flames
Abstract
This Phase I SBIR program investigated the application of Planar Laser-Induced Fluorescence (PLIF) to measurements of species concentration and temperature distributions in liquid-fueled spray flames. A bench-top spray burner was constructed and characterized with n-heptane fuel. Using laser sheet illumination, time-averaged and instantaneous distributions of the OH radical were obtained. Ratios of time-averaged OH distributions obtained from two isolated rotational levels were used to infer the time-averaged temperature in the hot, combustion product gases. Comparison of the PLIF temperature data with thermocouple scans suggest the technique is accurate to within about 5 percent. Time-averaged and mean distributions of NO seeded into the primary, atomizing air stream were also obtained. Preliminary ratios of two NO PLIF images obtained from separate rotational excitation were used to infer temperature in the cold, evaporating region of the flame. Initial relative temperature distributions appear correct, but further work is required to recover the absolute level. Using multiphoton photodissociation, instantaneous measurements of the C2H2 (and potentially other hydrocarbon fragments) were obtained in the pyrolyzing region of flame. The technique also revealed the instantaneous structure of the reaction zone.... PLIF, Laser-induced fluorescence, OH, NO, Photodissociation, C H, LIF thermometry.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1990
- Accession Number
- ADA260494
Entities
People
- Kathleen Donohue
- Mark G. Allen
- S. J. Davis
Organizations
- Physical Sciences (United States)