Characterization of Temperature and Soot Volume Fraction in Laminar Premixed Flames: Laser Absorption/Extinction Measurement and Two-Dimensional Computational Fluid Dynamics Modeling

摘要

We performed a comprehensive laser absorption/extinction study of temperature and soot volume fraction (SVF) in C2H4/air premixed sooting flames. Laser-absorption two-line thermometry at 2.5 mu m provided a temperature uncertainty of 50 K compared with that of 90 K using conventional thermocouples. Laser extinction of soot at 633 nm was first validated against the previous measurements using laser-induced incandescence. All of the measurements were conducted at four representative C2H4 flame conditions (equivalence ratio Phi = 1.78, 1.95, 2.14, and 2.38). In addition, a CFD (computational fluid dynamics) framework coupling a skeletal mechanism (56 species and 428 reactions) with the Moss-Brookes model was developed for interpreting the experimental data. The current CFD simulations well predicted the temperature and SVF distribution along the centerline of flame. It is of interest to observe that the SVF depends on the Reynolds number of reactants by investigating the SVFs at different heights above the burner for the varied flow rates and equivalence ratios.