Soot Aerosol Formation and Morphology in High Pressure Combustion
10:45 - 11:15
Level 0 lecture hall between Al-Jazri and Al-Kindi (buildings 4 and 5)
The morphology and structure of the combustion generated soot aggregates have been shown to have a significant influence on the optical and radiative transfer properties. The absorption cross section of soot aggregates, for example, is controlled by its optical properties and microphysical structure. Unraveling the sensitivity of soot processes to elevated pressures is important because combustion devices used in transporation operate at high pressures and it has been shown that the pressure has a significant influence on soot processes. However, the rate determining chemical reactions of combustion, including those involved in soot processes, are nonlinear in nature, and as a result the sensitivity of combustion events to changes in pressure are not usually monotonic. Consequently, it is a problematic issue to project the results inferred from experimental measurements in atmospheric flames to high-pressure combustion with confidence. Majority of the soot formation studies reported in the literature were conducted at atmospheric pressure, but the recent efforts at KAUST and UTIAS have been contributing to an experimental database of high-pressure soot properties and propensities of various fuels. In this talk, soot measurements at elevated pressures at UTIAS in non-premixed laminar flames focussing on the effect of combustion pressure on soot formation and soot aggregate morphology, including the primary soot particle size, will be presented and the relevance of the results to practical combustion systems will be discussed.