Laser-Induced Fluorescence Thermometry of a Weakly Ionized Radio-Frequency Plasma
Abstract
Results are reported of two-line laser-induced fluorescence thermometry measurements in a weakly ionized, radiofrequency plasma. The work was performed in support of hypervelocity studies in the AEDC SI Impact Range. Rotational temperatures of nitric oxide were determined to be in the range 1000-2000 K, based on excitation of two lines in the NO A-X (0,0) band. A data analysis procedure is described for separating the weak, laser-induced fluorescence signals from natural emission from the plasma. By comparing temperatures from a strong and a weak beam, it is demonstrated that optical saturation is avoided. A strong correlation is found between the PLIF-derived NO temperatures and the intensity of natural emission from the plasma. This correlation is used to estimate the temperature distribution in the plasma outside the region that was accessible to interrogation by the laser sheets.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 11, 1999
- Accession Number
- ADA368296
Entities
People
- Linwood L. Price
- Michael S. Smith
- Wim Ruyten