TY - JOUR
T1 - An experimental apparatus to measure soot morphology at high pressures using multi-angle light scattering
AU - Amin, Hafiz M.F.
AU - Roberts, William L.
PY - 2019/6/14
Y1 - 2019/6/14
N2 - In this work, a novel experimental setup is described which is designed
and built specifically to study soot morphology using light scattering
and extinction techniques at elevated pressures. The experimental setup
consists of a counterflow burner housed inside a pressure vessel. A
unique feature of this pressure vessel is the four curved optical
windows which can provide the required optical access for light
scattering measurements in order to infer the morphological parameters
of soot. Using this setup, N2-diluted ethylene and air counterflow flames are stabilized from 3 to 5 atm. Global strain rate (a) of 30 s−1
is maintained at all conditions and all the flames studied are soot
formation (SF) flames. Light scattering by soot is measured between 15°
to 165° at different locations along the axis of the burner. Ratio of
total scattering to absorption (ρsa), path averaged soot volume fraction (f v), mean primary particle size (dp), mean radius of gyration of aggregates (Rgm) and fractal dimension (Df)
are calculated from multi-angle light scattering and extinction data
using Rayleigh–Debye–Gans theory for fractal aggregates (RDG-FA). ρsa, f v, dp, and Rgm
increase as the pressure is raised. The scattering contribution in
these measurements vary from 1.3% to 16% of absorption which suggests
that wide angle optical access is essential for accurate measurements of
f v. Df equal to 1.27 is measured near the flame at 3 atm which increases as the particles are convected away from the flame and Df increases to 1.98 at 5 atm.
AB - In this work, a novel experimental setup is described which is designed
and built specifically to study soot morphology using light scattering
and extinction techniques at elevated pressures. The experimental setup
consists of a counterflow burner housed inside a pressure vessel. A
unique feature of this pressure vessel is the four curved optical
windows which can provide the required optical access for light
scattering measurements in order to infer the morphological parameters
of soot. Using this setup, N2-diluted ethylene and air counterflow flames are stabilized from 3 to 5 atm. Global strain rate (a) of 30 s−1
is maintained at all conditions and all the flames studied are soot
formation (SF) flames. Light scattering by soot is measured between 15°
to 165° at different locations along the axis of the burner. Ratio of
total scattering to absorption (ρsa), path averaged soot volume fraction (f v), mean primary particle size (dp), mean radius of gyration of aggregates (Rgm) and fractal dimension (Df)
are calculated from multi-angle light scattering and extinction data
using Rayleigh–Debye–Gans theory for fractal aggregates (RDG-FA). ρsa, f v, dp, and Rgm
increase as the pressure is raised. The scattering contribution in
these measurements vary from 1.3% to 16% of absorption which suggests
that wide angle optical access is essential for accurate measurements of
f v. Df equal to 1.27 is measured near the flame at 3 atm which increases as the particles are convected away from the flame and Df increases to 1.98 at 5 atm.
UR - http://www.scopus.com/inward/record.url?scp=85069002986&partnerID=8YFLogxK
U2 - 10.1088/1361-6501/ab1c3f
DO - 10.1088/1361-6501/ab1c3f
M3 - Article
AN - SCOPUS:85069002986
SN - 0957-0233
VL - 30
JO - Measurement Science and Technology
JF - Measurement Science and Technology
IS - 7
M1 - 075902
ER -