Journal of Zhejiang University SCIENCE A
ISSN 1673-565X(Print), 1862-1775(Online), Monthly

2009   Vol. 10   No. 9   p. 1320~1326

A 3D numerical simulation of laser-induced incandescence of soot particles in coal combustion products

Ling-hong CHEN^†1, Ke-fa CEN¹, Annie GARO², Gérard GREHAN²

(¹State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China)
(²LESP, UMR 6614/CORIA, CNRS/Université et INSA de Rouen, Saint Etienne du Rouvray, 76800, France)
^†E-mail: chenlh@zju.edu.cn
Received July 14, 2009; revision accepted Aug. 3, 2009; Crosschecked Aug. 3, 2009

Abstract: Laser-induced incandescence (LII) has received increasing attention as a potentially powerful technique for in-situ measuring of the volume fraction and primary size of soot particles in combustion systems. In this study, a 3D Monte Carlo simulation combined with a Mie equation was developed to analyze the influence of spectral absorption and scattering on the measured LII flux emitted by soot particles. This paper represents a first attempt to analyze soot measurement using the LII technique in coal combustion products. The combustion products of gases (CO₂, N₂), soot, and fly-ash particles, present between the location of laser-excited soot and the LII flux receiver. The simulation results indicated that an almost Beer-Lambert exponential decrease in LII flux occurred with an increase in the volume fraction of soot particles, while a nearly linear decrease occurred with an increase in the volume fraction of fly-ash particles. The results also showed that scattering effects of both soot and fly-ash particles on the LII flux could be neglected. Compared with the absorption of gases, a decrease of 20% of LII flux was observed with soot particles, and a decrease of 10% with fly-ash particles.

Key words: Laser-induced incandescence (LII), Soot, Fly-ash, 3D Monte Carlo, Scattering, Absorption
doi:10.1631/jzus.A0930003             CLC number: TK01; O59

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