High-speed visible supercontinuum laser absorption spectroscopy of metal oxides
Abstract
Supercontinuum laser absorption spectroscopy is applied to energetic material combustion fireball environments using the visible spectrum for temperature and column density measurements of key metal combustion intermediates TiO and AlO. Fireballs are produced by igniting metal/ammonium perchlorate powder beds on a thermal-jump apparatus. This work marks, to our knowledge, the first quantitative absorption measurement of TiO ( B 2 Π r − X 2 Δ r , Δ v = 0 ) and demonstrates the feasibility of broadband visible metal-oxide absorption thermometry at rates up to 100 kHz. We also demonstrate the capability for single laser-shot absorption measurements. The mean AlO ( B 2 Σ + − X 2 Σ + , Δ v = 0 ) temperature is 3010 K, whereas TiO has a mean temperature of 2095 K; both agree well with previous literature. Typical signal-to-noise ratios for the TiO and AlO absorption spectra are 22. The 100 kHz measurement rate reveals the time dynamics of titanium combustion—illustrating the potential for broadband multispecies monitoring in dynamic fireball environments.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 01, 2021
- Source ID
- 10.1364/ol.428456
Entities
People
- Anthony C. Locurto
- James Bret Michael
- Michael A. Welch
- Travis R. Sippel
Organizations
- Defense Threat Reduction Agency
- Iowa State University