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

Abstract

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

Document Details

Document Type
Pub Defense Publication
Publication Date
Sep 01, 2021
Source ID
10.1364/oe.435506

Entities

People

  • Christopher S. Goldenstein
  • Ryan J. Tancin

Organizations

  • Air Force Office of Scientific Research
  • National Aeronautics and Space Administration
  • National Science Foundation
  • Purdue University

Tags

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Optical Physics and Photonics.
  • Rocket Propulsion.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers