Rapid tuning cw laser technique for measurements of gas velocity, temperature, pressure, density, and mass flux using NO.

An intracavity-doubled rapid-tuning cw ring dye laser was used to acquire fully resolved absorption profiles of NO line pairs in the A ? X band at 225 nm at a rate of 4 kHz. These profiles were utilized for simultaneous measurements of flow parameters in the high speed 1-D flows generated in a shock tube. Velocity was determined from the Doppler shift measured using a pair of profiles simultaneously acquired at different angles with respect to the flow direction. Temperature was determined from the intensity ratio of the adjacent lines. Pressure and density were found both from the collisional broadening and the fractional absorption. From this information the mass flux was determined. The results compare well to 1-D shock calculations.

[1]  P. E. Rouse,et al.  BETA AND GAMMA BAND SYSTEMS OF NITRIC OXIDE. , 1969 .

[2]  Lester T. Earls.  Intensities inΠ2−Σ2Transitions in Diatomic Molecules , 1935 .

[3]  H. Mirels.  Correlation Formulas for Laminar Shock Tube Boundary Layer , 1966 .

[4]  R. W. Nicholls,et al.  Molecular constants for the v″ = 0 (X2Π) and v′ = 0, 1 (A2Σ+) levels of the NO molecule and its isotopes , 1980 .

[5]  H. Matsui,et al.  Vibrational relaxation of nitric oxide in argon , 1970 .

[6]  R. S. Mulliken,et al.  Λ-Type Doubling and Electron Configurations in Diatomic Molecules , 1931 .

[7]  R. Mckenzie,et al.  Two-photon excitation of nitric oxide fluorescence as a temperature indicator in unsteady gasdynamic processes. , 1981, Applied optics.

[8]  R. R. Reddy,et al.  The effect of high rotational quantum numbers on Franck-Condon factors , 1982 .

[9]  R. Miles,et al.  Supersonic-nitrogen flow-field measurements with the resonant Doppler velocimeter , 1983 .

[10]  L. Dodge,et al.  Line broadening and oscillator strength measurements for the nitric oxide γ(0,0) band , 1980 .

[11]  G. Herzberg,et al.  Constants of diatomic molecules , 1979 .

[12]  P. Logan,et al.  Measurements of temperature, density, pressure, and their fluctuations in supersonic turbulence using laser-induced fluorescence , 1987 .

[13]  D. Crosley,et al.  Calculated rotational transition probabilities for the A−X system of OH , 1980 .

[14]  A. Timmermann,et al.  Doppler-free two-photon excitation of nitric oxide with frequency-stabilized cw dye laser radiation , 1981 .

[15]  R. Hanson,et al.  Simultaneous measurements of velocity, temperature, and pressure using rapid cw wavelength-modulation laser-induced fluorescence of OH. , 1990, Optics letters.

[16]  Ronald K. Hanson,et al.  Shock-tube study of pressure broadening of the A2∑+ - X2Π (0,0) band of OH by Ar and N2 , 1987 .

[17]  R. Hanson,et al.  Instantaneous temperature field measurements using planar laser-induced fluorescence. , 1985, Optics letters.

[18]  R. Horsfall,et al.  The Spectra of Neutral and Ionized Boron Hydride , 1937 .

[19]  H. Scheingraber,et al.  Measurement of Hönl–London factors on 2Σ+–2Π transitions in NO , 1985 .

[20]  R. Hanson,et al.  Continuous wave laser absorption techniques for gasdynamic measurements in supersonic flows. , 1991, Applied optics.

[21]  R. Hanson,et al.  Molecular velocity imaging of supersonic flows using pulsed planar laser-induced fluorescence of NO. , 1989, Optics letters.