OH and soot concentration measurements in a high-temperature laminar diffusion flame

Journal Article · Mon Dec 01 04:00:00 EST 1997 · Combustion and Flame

DOI:https://doi.org/10.1016/S0010-2180(97)00003-5· OSTI ID:543512

Haudiquert, M; Cessou, A; Stepowski, D; Coppalle, A ^[1]

---

1. Univ. de Rouen, Mont-Saint-Aignan (France)

OH absorption and soot extinction coefficients have been determined in a sooting ethylene laminar diffusion flame produced above a Wolfhard-Parker burner. An oxidizer rich in oxygen provided a flame with a high-temperature combustion zone (T {approximately} 2,500 K). Compared to an ethylene-air flame, the production of OH is more pronounced, and soot burns out; thus, it is easier to study the oxidation of soot. 2D fluorescence images were obtained with a laser sheet tuned on and off the OH resonance frequency. A strategy, based on the relative shape of the signal in the direction of the laser at a given height above the burner, was developed to derive the local OH absorption coefficient and, in the sooting zone, the extinction coefficient. On the flame`s axis, the temperature was determined by two-color pyrometry; the absolute concentration of OH was derived from the absorption coefficients. Along the flame`s axis, profiles of OH and soot concentrations were obtained over the zone where soot oxidation takes place. The collision efficiency for OH was determined from these measurements. Just above the soot burn-out zone, [OH] was found to be lower than the value calculated assuming equilibrium.

• OSTI ID: 543512
• Journal Information: Combustion and Flame, Journal Name: Combustion and Flame Journal Issue: 4 Vol. 111; ISSN CBFMAO; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
54 ENVIRONMENTAL SCIENCES
CHEMICAL REACTION YIELD
COMBUSTION KINETICS
ETHYLENE
FLAMES
FLUORESCENCE
HYDROXYL RADICALS
OXIDATION
SOOT