Ultrafast-laser-absorption spectroscopy in the mid-infrared for single-shot, calibration-free temperature and species measurements in low- and high-pressure combustion gases

This manuscript presents an ultrafast-laser-absorption-spectroscopy (ULAS) diagnostic capable of providing calibration-free, single-shot measurements temperature and CO at 5 kHz in combustion gases low high pressures. Additionally, this was extended to provide 1D, a propellant flame. A detailed description the spectral-fitting routine, data-processing procedures, determination instrument response function are also presented. The accuracy validated 1000 K pressures up 40 bar heated-gas cell before being applied characterize spatiotemporal evolution AP-HTPB AP-HTPB-aluminum flames between 1 bar. results presented here demonstrate that ULAS mid-IR can high-fidelity, calibration-free gas properties with sub-nanosecond time resolution harsh, high-pressure environments representative rocket motors.