3D Laser Absorption Imaging of Species and Temperature in Supercritical Flames
Abstract
The primary research objective of this project was to enable and apply a novel three-dimensional, quantitative imaging technique for species and temperature in high pressure reacting flows. We proposed to achieve this objective via two advancements in laser diagnostics. First, we focused on expanding state-of-the-art laser absorption spectroscopy (LAS) methods in spatial resolution capability by utilizing high-speed infrared cameras to image flow fields backlit with tunable infrared laser radiation. The laser absorption imaging (LAI) technique provides for spectrally, spatially, and temporally rich datasets that can be reconstructed using tomographic methods. Second, we exploit the vibrational band and cluster narrowing effects of line mixing at high gas densities to extend laser absorption spectroscopy to pressures up to 100 atm for multiple combustion species. In this project, we work on both methods in parallel and aim to combine the novel imaging and high-density spectroscopic strategy for simultaneous measurements of both flame structure and quantitative thermochemistry (temperature, species concentrations) at extreme conditions, providing unique capability that does not exist with established diagnostic methods. In total, this project resulted in 10 peer-reviewed journal articles that reflect a progressive increase in dimensionality of the LAI method, integrated advances in data science and image processing, and spectroscopic studies at high pressures and temperatures. This report highlights the technical work primarily from the final year of the YIP award (other works were highlighted in prior progress reports). We built on the prior years to make progress on the two research fronts (laser absorption imaging and high-pressure spectroscopy) as described in this report.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 10, 2023
- Accession Number
- AD1230633
Entities
People
- R. Mitchell Spearrin
Organizations
- University of California, Los Angeles