Simultaneous measurements of soot volume fraction and particle size / microstructure in flames using a thermophoretic sampling technique

Köylü, Ümit Özgür; McEnally, Charles S.; Rosner, Daniel E.; Pfefferle, Lisa D.

doi:10.1016/s0010-2180(97)00089-8

Cited by 209 publications

(82 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Particle size distribution can be measured by transmission-electron microscopy following thermophoretic sampling in flames, and a recent publication reported measurement of a standard deviation in primary particle size of 20%. 43 The heat-transfer model for laser-heated particles was tested by a theoretical sensitivity analysis similar to that described in Ref. 17.…”

Section: Discussionmentioning

confidence: 99%

Laser-induced incandescence for soot particle size measurements in premixed flat flames

2000

View full text Add to dashboard Cite

Measurements of soot properties by means of laser-induced incandescence ͑LII͒ and combined scatteringextinction were performed in well-characterized premixed ethylene-air flames. In particular, the possibility of using LII as a tool for quantitative particle sizing was investigated. Particle sizes were evaluated from the temporal decay of the LII signal combined with heat balance modeling of laser-heated particles, and these sizes were compared with the particle sizes deduced from scattering-extinction measurements based on isotropic sphere theory. The correspondence was good early in the sootformation process but less good at later stages, possibly because aggregation to clusters began to occur. A critical analysis has been made of how uncertainties in different parameters, both experimental and in the model, affect the evaluated particle sizes for LII. A sensitivity analysis of the LII model identified the ambient-flame temperature as a major source of uncertainty in the evaluated particle size, a conclusion that was supported by an analysis based on temporal LII profiles.

show abstract

Section: Discussionmentioning

confidence: 99%

Laser-induced incandescence for soot particle size measurements in premixed flat flames

2000

View full text Add to dashboard Cite

show abstract

“…They have been widely depicted in micrographs obtained by ex-situ sampling from flames where they appear as solitary, sometimes faint particles that are semi-transparent to the electron beam but they may display dark edges or dark internal regions. These nanoparticles have been shown in micrographs of samples from premixed flames (Wersborg et al 1973;Onichuk et al 2003;Sgro et al 2003;Öktem et al 2005), in numerous laminar diffusion flames (Megaridis et al 1989;Dobbins et al 1994Dobbins et al , 1996Dobbins et al , 1998Dobbins, 1997;Vander Wal, 1996Köylü et al 1997;Lee et al 2000); in turbulent flames (Hu et al 2003(Hu et al , 2004Yang et al 2005); in unsteady, flickering flames (Zhang and Megaridis 1998); in bituminous coal flames (Ma et al 1995); in microgravity flames (Konsur et al 1999); in inverse diffusion flames (Blevins et al 2002;Lee et al 2005;Oh et al 2005); in a two meter pool fire (Jensen et al 2005); in a well stirred reactor (Blevins et al 2003); and in an opposed flow flame (Merchan-Merchan et al 2003). Additional details concerning these studies are summarized in Table A1 of Appendix A.…”

Section: Precursor Nanoparticlesmentioning

confidence: 95%

“…Micrographs of these particles present a more opaque, black material, and they are shown by several investigations to undergo a serial transformation from precursor particles to aggregates (e.g., Dobbins 1997;Köylü et al 1997;Vander Wal 1997). Aggregated particles have high elemental carbon content and may have molecular species absorbed on external or interstitial surfaces.…”

Section: Carbonaceous Aggregatesmentioning

confidence: 99%

Hydrocarbon Nanoparticles Formed in Flames and Diesel Engines

Dobbins

2007

Aerosol Science and Technology

View full text Add to dashboard Cite

The formation of nanoparticles in laboratory hydrocarbon flames is reviewed in terms of particle morphology, chemical composition, and health hazards. The nascent nanoparticles in the nucleation mode have been widely reported in diverse laboratory flames, and are distinguished by their occurrence as singlet particles that form translucent images in transmission electron microscopy (TEM). Their sizes range from about 10 nm or more down to 2 to 3 nm, the limit of resolution of the TEM, and they possess a liquid-like quality. These particles are widely considered to be the precursor stage to the more readily observed carbonaceous aggregates consisting of chained primary particles that are opaque to the electron beam of the TEM. Nanoparticles sampled from the inverse diffusion flame and the particle effluent from diesel engines show a strong resemblance by GCMS analysis, and they contain many of the stabilomer PAHs and their isomers in the 200 to 302 atomic mass range. Many of these chemical species have high relative mutagenicities. Distinctive bimodal particle size distributions can be observed in both flame and engine samples. Recent TEM micrographs of diesel particulates show images of precursor-like nanoparticles, of as yet unknown chemical composition, that are formed in a diesel engine at many operating conditions.

show abstract

“…The Guinier part of the angular scattering function describes the light scattered by the aggregates at small angles (as opposed to the power-law for the larger angles), mainly responsible for the extinction measured by the DBIEI diagnostic. The values of D f and k f were determined to be 1.77 and 8.36, respectively, by fitting the TEM-extracted distribution using a method similar to that proposed by Köylü et al [53].…”

Section: Skeen Et Al / Sae Int J Engines / Volume 9 Issue 2 (June mentioning

confidence: 99%

A Progress Review on Soot Experiments and Modeling in the Engine Combustion Network (ECN)

Skeen

Manin

Pickett

et al. 2016

SAE Int. J. Engines

View full text Add to dashboard Cite

The 4th Workshop of the Engine Combustion Network (ECN) was held September 5-6, 2015 in Kyoto, Japan. This manuscript presents a summary of the progress in experiments and modeling among ECN contributors leading to a better understanding of soot formation under the ECN “Spray A” configuration and some parametric variants. Relevant published and unpublished work from prior ECN workshops is reviewed. Experiments measuring soot particle size and morphology, soot volume fraction (fv), and transient soot mass have been conducted at various international institutions providing target data for improvements to computational models. Multiple modeling contributions using both the Reynolds Averaged Navier-Stokes (RANS) Equations approach and the Large-Eddy Simulation (LES) approach have been submitted. Among these, various chemical mechanisms, soot models, and turbulence-chemistry interaction (TCI) methodologies have been considered

show abstract

Simultaneous measurements of soot volume fraction and particle size / microstructure in flames using a thermophoretic sampling technique

Cited by 209 publications

References 24 publications

Laser-induced incandescence for soot particle size measurements in premixed flat flames

Laser-induced incandescence for soot particle size measurements in premixed flat flames

Hydrocarbon Nanoparticles Formed in Flames and Diesel Engines

A Progress Review on Soot Experiments and Modeling in the Engine Combustion Network (ECN)

Contact Info

Product

Resources

About