Two-Beam Femtosecond Rotational CARS for One-Dimensional Thermometry in a Turbulent, Sooting Jet Flame

Single-laser-shot femtosecond rotational coherent anti-Stokes Raman scattering (fs-RCARS) temperature measurements are performed across a 6-mm line in a turbulent, sooting ethylene jet flame to characterize temperature gradients. A 60fs pulse is used to excite many rotational Raman transitions in N-2, and a 160-ps pulse is used to probe the Raman coherence. The spatial resolution of the measurements is 500 mu m in the direction of beam propagation and 50 mu m in the transverse directions. Measurements have been performed at multiple locations in the jet flame, and the measured temperature are similar to previously recorded point measurements. Future work will include performing simultaneous laser-induced incandescence (LII) measurements to measure soot volume fraction to perform joint statistical analysis of the sooting turbulent flame.