- Author
-
Manzello, S. L.
|
Lee, E. J.
|
Mulholland, G. W.
- Title
- Use of Laser-Induced Ionization to Detect Soot Inception in Premixed Flames.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
Korea Institute of Construction and Technology, II-San City, South Korea
- Journal
-
Applied Optics,
Vol. 44,
No. 24,
5105-5111,
August 20, 2005
- Keywords
-
premixed flames
|
lasers
|
ionization
|
soot
|
instruments
|
combustion
- Identifiers
- laser-induced-ionization measurements; ethene-air premixed flames; soot-inception point
- Abstract
- Experimental measurements of laser-induced ionization were performed for ethene-air premixed flames operated near the soot inception point. Soot was ionized with a pulsed laser operated at 532 nm. The ionization signal was collected with a tungsten electrode located in the postflame region. Ionization signals were collected by use of both single-electrode and dual-electrode configurations. Earlier laser-induced- ionization studies focused on the use of a single biased electrode to generate the electric field, with the burner head serving as the path to ground. In many practical combustion systems, a path to ground is not readily available. To apply the laser-induced- ionization diagnostic to these geometries, a dual-electrode geometry must be employed. The influence of electrode configuration, flame equivalence ratio, and flame height on ionization signal detection was determined. The efficacy of the laser-induced-ionization diagnostic in detecting soot inception in the postflame region of a premixed flame by use of a dual-electrode configuration was investigated. Of the dual-electrode configurations tested, the dual-electrode geometry oriented parallel to the laser beam was observed to be most sensitive for detecting the soot inception point in a premixed flame.