Publications
Dual-pump CARS thermometry in sooting acetylene-fueled flames
We investigate the utility of dual-pump coherent anti-Stokes Raman scattering (CARS) for investigations of fuel-rich flames with soot volume loadings up to 2.2 ppm. Our initial characterization of a gas-phase propellant simulating burner is presented. The burner investigated consists of alternating fuel and oxidizer tubes with the option for injection of aluminum particles into the flame. We focus on a C2H2-N2-O2 flame, in which no aluminum particles are yet added. For the required flow rates, this burner provides an array of heavily sooting and highly luminous diffusion flames whose temperature is measured by dual-pump CARS. The nature of the observed soot-induced interference in the CARS spectra for several different pump 2 frequencies is documented and CARS temperatures obtained from data in a spectrally "quiet" region, with the CARS signal beam near 483 nm, are presented. Soot volume fractions are imaged by absorption-calibrated laser-induced incandescence (LII) to quantify the soot loadings at which our dual-pump CARS facility provides reliable measurements.