caa a22 4500 445370335 CHVBK 20180317142944.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s00340-011-4416-4 doi (NATIONALLICENCE)springer-10.1007/s00340-011-4416-4 Examination of wavelength dependent soot optical properties ofdiesel and diesel/rapeseed methyl ester mixture by extinction spectra analysis and LII measurements [Elektronische Daten] [J. Yon, R. Lemaire, E. Therssen, P. Desgroux, A. Coppalle, K. Ren] The refractive index of soot is an essential parameter for its optical diagnostics. It is necessary for quantitative interpretation of LII (Laser Induced Incandescence) signals, light scattering or extinction measurements as well as for emissivity calculations. The most cited values have been determined by intrusive methods or without taking into account the soot size distribution and its specific morphology. In the present study, soot generated by the combustion of diesel and diesel/rapeseed methyl ester (RME) mixture (70% diesel and 30% RME) are extensively characterized by taking into account the morphology, the aggregate size distribution, the mass fraction and the spectral dispersion of light. The refractive index m for wavelengths λ between 300 and 1000nm is determined for diesel and diester fuels by both in-situ and ex-situ methods. The ex-situ method is based on the interpretation of extinction spectra by taking into account soot sizes and fractal morphology with the RDG-FA (Rayleigh-Debye-Gans for Fractal Aggregate) theory. The in-situ approach is based on the comparison of the LII signals obtained with two different excitation wavelengths. The absorption function E(m) and the scattering function F(m) are examined. This study reveals similar optical properties of soot particles generated by both studied fuels even at ambient and flame temperatures. The function E(m) is shown to reach a maximum for λ=250nm and to tend toward a plateau-like behavior close to E(m)=0.3 for higher wavelength (600<λ(nm)<1000). The function F(m) is found to be quite constant for 400<λ(nm)<1000 and equal to 0.31. Springer-Verlag, 2011 Yon J. CNRS UMR 6614—CORIA, Université et INSA de Rouen, BP-12, 76801, Saint Etienne du Rouvray, France aut Lemaire R. Université Lille Nord de France, 59000, Lille, France aut Therssen E. Université Lille Nord de France, 59000, Lille, France aut Desgroux P. Université Lille Nord de France, 59000, Lille, France aut Coppalle A. CNRS UMR 6614—CORIA, Université et INSA de Rouen, BP-12, 76801, Saint Etienne du Rouvray, France aut Ren K. CNRS UMR 6614—CORIA, Université et INSA de Rouen, BP-12, 76801, Saint Etienne du Rouvray, France aut Applied Physics B Springer-Verlag 104/2(2011-08-01), 253-271 0946-2171 104:2<253 2011 104 340 https://doi.org/10.1007/s00340-011-4416-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00340-011-4416-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yon J. CNRS UMR 6614—CORIA, Université et INSA de Rouen, BP-12, 76801, Saint Etienne du Rouvray, France aut NATIONALLICENCE 700 1- Lemaire R. Université Lille Nord de France, 59000, Lille, France aut NATIONALLICENCE 700 1- Therssen E. Université Lille Nord de France, 59000, Lille, France aut NATIONALLICENCE 700 1- Desgroux P. Université Lille Nord de France, 59000, Lille, France aut NATIONALLICENCE 700 1- Coppalle A. CNRS UMR 6614—CORIA, Université et INSA de Rouen, BP-12, 76801, Saint Etienne du Rouvray, France aut NATIONALLICENCE 700 1- Ren K. CNRS UMR 6614—CORIA, Université et INSA de Rouen, BP-12, 76801, Saint Etienne du Rouvray, France aut NATIONALLICENCE 773 0- Applied Physics B Springer-Verlag 104/2(2011-08-01), 253-271 0946-2171 104:2<253 2011 104 340 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer