Soot sublimation studies in a premixed flat flame using laser-induced incandescence (LII) and elastic light scattering (ELS)

NE Olofsson, J Johnsson, H Bladh, PE Bengtsson - Applied Physics B, 2013 - Springer
NE Olofsson, J Johnsson, H Bladh, PE Bengtsson
Applied Physics B, 2013Springer
Laser-induced incandescence (LII) as a diagnostic technique is based on rapid heating of
soot particles to temperatures of several thousand Kelvin and subsequent detection of the
thermal radiation from the laser-heated particles. At such high temperatures, soot
sublimation effects must be considered when estimating uncertainties in LII measurements.
In this work we have investigated the use of various laser fluences in LII using a Nd: YAG
laser at 1,064 nm. Using another Nd: YAG laser at 532 nm, the elastic light scattering (ELS) …
Abstract
Laser-induced incandescence (LII) as a diagnostic technique is based on rapid heating of soot particles to temperatures of several thousand Kelvin and subsequent detection of the thermal radiation from the laser-heated particles. At such high temperatures, soot sublimation effects must be considered when estimating uncertainties in LII measurements. In this work we have investigated the use of various laser fluences in LII using a Nd:YAG laser at 1,064 nm. Using another Nd:YAG laser at 532 nm, the elastic light scattering (ELS) signal from soot particles heated by the 1,064-nm laser was monitored. This approach makes it possible to determine at which fluence of the LII laser soot sublimation starts to become visible as a decrease in the ELS signal. By performing the measurements at various heights in a premixed sooting flat ethylene/air flame, the fluence threshold above which the ELS signal decreased was found to be higher at the lower flame heights corresponding to younger, smaller and less aggregated particles. The results from this work indicate that the different fluence thresholds for sublimation may be explained by a lower absorption function E(m) for the younger soot particles.
Springer
以上显示的是最相近的搜索结果。 查看全部搜索结果