WIDECARS Measurements of a Premixed Ethylene-Air Flame in a Small-Scale Dual-Mode Scramjet Combustor

摘要

Width increased dual-pump enhanced coherent anti-Stokes Raman spectroscopy (WIDECARS) measurements of a premixed air-ethylene flame were conducted in a direct connect small-scale dual-mode scramjet combustor, at University of Virginia Supersonic Combustion Facility (UVaSCF). A nominal Mach 5 flight condition was simulated (stagnation pressure p_0 = 300 kPa, temperature T_0 = 1200 K, equivalence ratio range ER = 0.3 - 0.4). The purpose of this test was to provide quantitative measurements of six major combustion species (C_2H_4, N_2, O_2, H_2, CO, CO_2) concentration and temperature simultaneously. Measurements were taken, point to point, by mapping four two dimensional orthogonal planes (before, within, and two planes after the cavity flame holder) with respect to the combustor free stream. Two hundred single shot recorded spectra were processed and theoretically fitted. Mean flow and standard deviation are provided for each investigated case. Within the flame limits tested, WIDECARS data were analyzed and compared with CFD simulations and OH-PLIF measurements.