Measurement of dimensionless soot extinction constant using a gravimetric sampling technique

• Published in: Experimental thermal and fluid science Vol. 18; no. 1; pp. 27 - 32
• Main Authors: Zhou, Zhi-Qiang, Ahmed, Tasleem U., Y. Choi, Mun
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01-09-1998; Elsevier Science
• Subjects: Acetylene; Air; Air pollution caused by fuel industries; Applied sciences; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Gravimetric analysis; Gravimetric sampling; Light extinction; Light extinction technique; Metering. Control; Optical properties; Soot; Soot extinction constant; Soot extinction constant; Light extinction technique; Gravimetric sampling; Soot; Optical properties; Measurement; Gravimetric analysis; Premixed flame; Air pollution; Optical extinction; Acetylene
• ISSN: 0894-1777; 1879-2286
• DOI: 10.1016/S0894-1777(98)10005-5

The dimensionless extinction constant,
K
e, of post-flame soot from rich acetylene/air premixed flames was measured using a simultaneous gravimetric-sampling and light extinction technique at a wavelength of 632.8 nm. The average value of
K
e is 8.5 with a standard deviation of 0.5. An important improvement in the present method include the reduction in the uncertainty of the extinction pathlength and uniformity of the soot concentration in the probed region. Several aspects of the experimental procedure which can potentially introduce errors in the measured
K
e were evaluated. Results indicate that
K
e is only moderately influenced by the sampling flowrate and that the variation is minimized when flowrates are maintained close to isokinetic conditions. It is demonstrated that moisture condensation within the sampling probe, if disregarded, can produce large errors in
K
e.