Abstract

A variant of laser saturation spectroscopy has been applied to the determination of spatially resolved temperature in low-pressure supersonic flows. By copropagating a pump and probe beam with a small crossing angle, the full Doppler profile is retained, but the signal is limited to the volume where both beams are overlapped. The technique was demonstrated on several rovibrational lines of the ${\mathrm{I}}_{2}X{}^1\mathrm{\Sigma }(0_g^{+})\to B{}^3\mathrm{\Pi }(0_u^{+})$ transition in a Mach 2 Laval nozzle. A temperature of $146\mathrm{K}\pm 1.5\mathrm{K}$ was extracted from measurements of the ${\mathrm{I}}_2$ $P(46)$ 17-1 spectral line with a spatial resolution of $2.4{\mathrm{mm}}^3$. Application of the technique to the turbulent gain medium of a chemical oxygen–iodine laser is discussed.

© 2009 Optical Society of America

Temporally resolved, two-line fluorescence imaging of NO temperature in a transverse jet in a supersonic cross flow

Brian K. McMillin, Jennifer L. Palmer, and Ronald K. Hanson
Appl. Opt. 32(36) 7532-7545 (1993)

Temperature imaging in a supersonic free jet of combustion gases with two-line OH fluorescence

Jennifer L. Palmer and Ronald K. Hanson
Appl. Opt. 35(3) 485-499 (1996)

Temperature measurements in gases by use of planar laser-induced fluorescence imaging of NO

Michael P. Lee, Brian K. McMillin, and Ronald K. Hanson
Appl. Opt. 32(27) 5379-5396 (1993)

Arcjet nozzle flow-field characterization by laser-induced fluorescence

P. Victor Storm and Mark A. Cappelli
Appl. Opt. 37(3) 486-495 (1998)

Nitric-oxide planar laser-induced fluorescence applied to low-pressure hypersonic flow fields for the imaging of mixture fraction

Tobias Rossmann, M. Godfrey Mungal, and Ronald K. Hanson
Appl. Opt. 42(33) 6682-6695 (2003)