An LII technique independent of ex-situ calibration by detecting absolute light intensity

International Bunsen Discussion Meeting and Workshop Laser-induced incandescence: Quantitative Interpretation, Modelling, Application

D. R. Snelling ; G. J. Smallwood ; F. Liu ; Ö. L. Gülder ; W. D. Bachalo

Others  :  http://CEUR-WS.org/Vol-195/snelling.pdf
PID  :  2843

来源: CEUR

【 摘 要 】

This paper presents a novel LII technique for the determination of soot volume fraction by measuring the absolute incandescence intensity, avoiding the need for ex situ calibration typically using a source of particles with known soot volume fraction. The technique developed in this study further extends the capabilities of existing LII for making practical quantitative measurements of soot. The spectral sensitivity of the detection system is determined by calibrating with an extended source of known radiance and this sensitivity is then used to interpret the measured LII signals. Although it requires knowledge of the soot temperature, either from a numerical model of soot particle heating or experimentally determined by detecting LII signals at two different wavelengths, this technique offers a calibration independent procedure for measuring soot volume fraction. Application of this technique to soot concentration measurements is demonstrated in a laminar diffusion flame. [first paragragh]