Quantitative measurements of soot particles in a laminar diffusion flame using a LII/LIS technique

Abstract

Methods to investigate soot formation are studied experimentally with a co-flow burner. In this study, the soot volume fraction, soot particle diameter and number density in a laminar diffusion flame are measured using LII/LIS (laser-induced incandescence/laser-induced scattering) techniques. For the purpose of quantification, validation tests needed to be conducted before the LII/LIS techniques were applied to measure soot formation, and the development of algorithm was also required to analyse the raw data. In the present study, extinction and scattering tests with a co-flow burner were performed to acquire calibration data. From these results, we decided the optimal laser beam intensity and obtained the LII signal from the diffusion flame. In addition, the algorithm for the LII/LIS simultaneous measurement was developed and applied to this algorithm to measure the soot volume fraction in the diffusion flame.