Simultaneous planar measurements of temperature and soot volume fraction in a turbulent non-premixed jet flame

Abstract

New measurements are reported of the soot–temperature interaction in a turbulent non-premixed ethylene–hydrogen–nitrogen attached jet flame with an exit Reynolds number of 15,000. Spatially resolved, two-dimensional temperature and soot volume fractions were measured simultaneously using non-linear excitation regime two-line atomic fluorescence (NTLAF) and laser-induced incandescence (LII) techniques, respectively. The soot–temperature correlation is presented and analyzed through representative images of single-shot simultaneous temperature and soot volume fraction at various heights, as well as through joint probability density functions (PDFs) of soot volume fraction (SVF) and temperature. A strong influence of temperature on SVF is found, which is consistent with current understanding of their inter-dependence. Axial and radial plots of mean SVF categorized into temperature bands of 300K are also reported. These reveal that, while the mean SVF is a function of both temperature and axial distance, the joint PDF depends only weakly on radial distance. The study highlights the value of the simultaneous measurements for understanding soot behavior in a turbulent environment and for model development and validation.