Observation and Real-Time Monitoring of Soot Superaggregates with Small Angle Light Scattering
RAIYA EBINI, Justin Maughan, Kurt Ehlers, Prakash Gautam, Hans Moosmüller, Christopher M. Sorensen, American Ecotech
Abstract Number: 446
Working Group: Aerosol Physics
Abstract
Superaggregates (SAs) are formed during late-stage aggregation near the gel point of an aggregating system [1], where Diffusion Limited Cluster-cluster Aggregation leads an overall structure with a fractal dimension Df ≈2.6 and a short-range structure with Df ≈1.8 [2]. This yields hybrid slopes in the fractal power law regime as seen in log-log plots of scattered intensity vs. wavevector [3]. SAs were first observed in diffusion flames [4] and are commonly emitted by heavily sooting and inverted flames [5, 6], pool fires [7], and forest fires [8], as result of cluster dense aggregation at cluster-cluster mean separation comparable to the mean cluster size.
Here, we observed SAs using small angle light scattering when burning toluene in a simple wick lamp. SAs are commonly generated in combustion processes and may also be important in the atmosphere where they could be monitored in real time with small angle light scattering methods.
References
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