Structure of a spray flame stabilized on a production engine combustor swirl cup

Book · Sat Dec 31 04:00:00 EST 1994

OSTI ID:93162

Takahashi, Fumiaki; Schmoll, W J ^[1]; Switzer, G L ^[2]; Shouse, D T ^[3]

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1. Univ. of Dayton Research Inst., OH (United States)
2. Systems Research Labs., Inc., Dayton, OH (United States)
3. Wright Lab., Wright-Patterson AFB, OH (United States). Aero Propulsion and Power Directorate

The near-field structure of a turbulent flame stabilized on a production gas-turbine engine combustor fuel injector/air swirler system (i.e., swirl cup) has been studied using phase-Doppler anemometry and coherent anti-Stokes Raman spectroscopy (CARS) at atmospheric pressure. A jet-A fuel spray from a simplex atomizer impinges onto a coaxially located liquid filming surface between counter swirling air streams for secondary atomization using high shear forces. An inverted conical flame with a cone angle of {approximately}90{degree} was formed in the inner shear layer of the low-temperature droplet-laden hollow-cone air jet, which divides high-temperature internal and external recirculation zones. Small droplets disappeared in the inner and downstream spray regions by evaporation along the droplet trajectories at higher temperatures and longer residence times, thereby increasing arithmetic and Sauter mean diameters. No fuel droplets were found in the internal recirculation zone. Despite frequent laser-induced breakdown in the dense spray region, CARS thermometry successfully determined the gas temperature. The temperature histograms show a wide distribution inside the flame zone, indicating enhanced stirring of cold air, vaporized fuel, and hot combustion products. On the other hand, the fate of fuel droplets, which did not participate in the combustion process directly in the near field, must play in important role in determining the combustion efficiency and pollutant emission levels.

• OSTI ID: 93162
• Report Number(s): CONF-940711--
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
33 ADVANCED PROPULSION SYSTEMS
ATOMIZATION
COMBUSTION KINETICS
DIAGNOSTIC TECHNIQUES
EXPERIMENTAL DATA
FLAMES
GAS TURBINE ENGINES
JET ENGINE FUELS
MORPHOLOGY
TEMPERATURE MEASUREMENT