Study of the Evolution of Soot Formation using Laser-induced Incandescence

Abstract

Soot particles usually cause respiratory diseases and other problems to human health. To prevent or at least reduces soot emissions it is necessary to know its formation mechanism. Laser-Induced Incandescence (LII) has been used to detect soot and its precursors, known as polycyclic aromatic hydrocarbons (PAHs), in diffusion flames. In this work, several mixtures of diesel/biodiesel blends were investigated using two laser wavelengths, at 532 nm, which excites both soot and PAHs, and at 1064 nm, which excites only soot. Thus, the difference of intensity between both LII signals provides the proportion of soot/PAHs in the irradiated regions of flames, and it can be associated to the evolution of soot formation along the flame.