Abstract

The development and initial demonstration of a scanned-wavelength, first-harmonic-normalized, wavelength-modulation spectroscopy with nf detection (scanned-WMS-nf/1f) strategy for calibration-free measurements of gas conditions are presented. In this technique, the nominal wavelength of a modulated tunable diode laser (TDL) is scanned over an absorption transition to measure the corresponding scanned-WMS-nf/1f spectrum. Gas conditions are then inferred from least-squares fitting the simulated scanned-WMS-nf/1f spectrum to the measured scanned-WMS-nf/1f spectrum, in a manner that is analogous to widely used scanned-wavelength direct-absorption techniques. This scanned-WMS-nf/1f technique does not require prior knowledge of the transition linewidth for determination of gas properties. Furthermore, this technique can be used with any higher harmonic (i.e., n>1), modulation depth, and optical depth. Selection of the laser modulation index to maximize both signal strength and sensitivity to spectroscopic parameters (i.e., gas conditions), while mitigating distortion, is described. Last, this technique is demonstrated with two-color measurements in a well-characterized supersonic flow within the Stanford Expansion Tube. In this demonstration, two frequency-multiplexed telecommunication-grade TDLs near 1.4 μm were scanned at 12.5 kHz (i.e., measurement repetition rate of 25 kHz) and modulated at 637.5 and 825 kHz to determine the gas temperature, pressure, H2O mole fraction, velocity, and absorption transition lineshape. Measurements are shown to agree within uncertainty (1%–5%) of expected values.

© 2014 Optical Society of America

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  1. R. K. Hanson, “Applications of quantitative laser sensors to kinetics, propulsion and practical energy systems,” Proc. Combust. Inst. 33, 1–40 (2011).
    [CrossRef]
  2. S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, “Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines,” Proc. Combust. Inst. 28, 587–594 (2000).
    [CrossRef]
  3. J. T. C. Liu, G. B. Rieker, J. B. Jeffries, M. R. Gruber, C. D. Carter, T. Mathur, and R. K. Hanson, “Near-infrared diode laser absorption diagnostic for temperature and water vapor in a scramjet combustor,” Appl. Opt. 44, 6701–6711 (2005).
    [CrossRef]
  4. G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
    [CrossRef]
  5. K. Sun, X. Chao, R. Sur, J. B. Jeffries, and R. K. Hanson, “Wavelength modulation diode laser absorption spectroscopy for high-pressure gas sensing,” Appl. Phys. B 110, 497–508 (2013).
    [CrossRef]
  6. R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
    [CrossRef]
  7. T. Fernholz, H. Teichert, and V. Ebert, “Digital, phase-sensitive detection for in situ diode-laser spectroscopy under rapidly changing transmission conditions,” Appl. Phys. B 75, 229–236 (2002).
    [CrossRef]
  8. J. Wolfrum, “Lasers in combustion: from basic theory to practical devices,” Proc. Combust. Inst. 27, 1–41 (1998).
  9. L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
    [CrossRef]
  10. L. C. Philippe and R. K. Hanson, “Laser diode wavelength-modulation spectroscopy for simultaneous measurement of temperature, pressure, and velocity in shock-heated oxygen flows,” Appl. Opt. 32, 6090–6103 (1993).
    [CrossRef]
  11. G. Wysocki, A. A. Kosterev, and F. K. Tittel, “Spectroscopic trace-gas sensor with rapidly scanned wavelengths of a pulsed quantum cascade laser for in situ NO monitoring of industrial exhaust systems,” Appl. Phys. B 80, 617–625 (2005).
    [CrossRef]
  12. M. G. Allen, “Diode laser absorption sensors for gas-dynamic and combustion flows,” Meas. Sci. Technol. 9, 545–562 (1998).
    [CrossRef]
  13. G. Hancock, J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker, “Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser,” Appl. Phys. Lett. 94, 201110 (2009).
    [CrossRef]
  14. T. R. Meyer, S. Roy, T. N. Anderson, R. P. Lucht, R. Barron-Jimenez, and J. R. Gord, “10 kHz detection of CO2 at 4.5 μm by using tunable diode-laser-based difference-frequency generation,” Opt. Lett. 30, 3087–3089 (2005).
    [CrossRef]
  15. M. Seiter and M. W. Sigrist, “On-line multicomponent trace-gas analysis with a broadly tunable pulsed difference-frequency laser spectrometer,” Appl. Opt. 38, 4691–4698 (1999).
    [CrossRef]
  16. V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
    [CrossRef]
  17. J. A. Silver, “Frequency-modulation spectroscopy for trace species detection: theory and comparison among experimental methods,” Appl. Opt. 31, 707–717 (1992).
    [CrossRef]
  18. D. S. Bomse, A. C. Stanton, and J. A. Silver, “Frequency modulation and wavelength modulation spectroscopies: comparison of experimental methods using a lead-salt diode laser,” Appl. Opt. 31, 718–731 (1992).
    [CrossRef]
  19. D. T. Cassidy and J. Reid, “Atmospheric pressure monitoring of trace gases using tunable diode lasers,” Appl. Opt. 21, 1185–1190 (1982).
    [CrossRef]
  20. G. B. Rieker, J. B. Jeffries, and R. K. Hanson, “Calibration-free wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Appl. Opt. 48, 5546–5560 (2009).
    [CrossRef]
  21. C. L. Strand and R. K. Hanson, “Thermometry and velocimetry in supersonic flows via scanned wavelength-modulation absorption spectroscopy,” in 47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2011), paper AIAA 2011-5600.
  22. L. S. Chang, J. B. Jeffries, and R. K. Hanson, “Mass flux sensing via tunable diode laser absorption of water vapor,” AIAA J. 48, 2687–2693 (2010).
    [CrossRef]
  23. J. Reid and D. Labrie, “Second-harmonic detection with tunable diode lasers—comparison of experiment and theory,” Appl. Phys. B 26, 203–210 (1981).
    [CrossRef]
  24. P. Werle, “Spectroscopic trace gas analysis using semiconductor diode lasers,” Spectrochim. Acta, Part A 52, 805–822 (1996).
    [CrossRef]
  25. D. T. Cassidy and L. J. Bonnell, “Trace gas detection with short-external-cavity InGaAsP diode laser transmitter modules operating at 1.58 μm,” Appl. Opt. 27, 2688–2693 (1988).
    [CrossRef]
  26. H. Li, G. B. Rieker, X. Liu, J. B. Jeffries, and R. K. Hanson, “Extension of wavelength-modulation spectroscopy to large modulation depth for diode laser absorption measurements in high-pressure gases,” Appl. Opt. 45, 1052–1061 (2006).
    [CrossRef]
  27. K. Duffin, A. J. McGettrick, W. Johnstone, G. Stewart, and D. G. Moodie, “Tunable diode-laser spectroscopy with wavelength modulation: a calibration-free approach to the recovery of absolute gas absorption line shapes,” J. Lightwave Technol. 25, 3114–3125 (2007).
    [CrossRef]
  28. J. R. P. Bain, W. Johnstone, K. Ruxton, G. Stewart, M. Lengden, and K. Duffin, “Recovery of absolute gas absorption line shapes using tunable diode laser spectroscopy with wavelength modulation—part 2: experimental investigation,” J. Lightwave Technol. 29, 987–996 (2011).
    [CrossRef]
  29. K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
    [CrossRef]
  30. X. Liu, J. B. Jeffries, and R. K. Hanson, “Measurements of spectral parameters of water-vapour transitions near 1388 and 1345 nm for accurate simulation of high-pressure absorption spectra,” Meas. Sci. Technol. 18, 1185–1194 (2007).
    [CrossRef]
  31. K. H. Lyle, J. B. Jeffries, and R. K. Hanson, “Diode-laser sensor for air-mass flux 1: design and wind tunnel validation,” AIAA J. 45, 2204–2212 (2007).
    [CrossRef]
  32. P. Kluczynski and O. Axner, “Theoretical description based on Fourier analysis of wavelength-modulation spectrometry in terms of analytical and background signals,” Appl. Opt. 38, 5803–5815 (1999).
    [CrossRef]
  33. P. Kluczynski, Å. M. Lindberg, and O. Axner, “Wavelength modulation diode laser absorption signals from Doppler broadened absorption profiles,” J. Quant. Spectrosc. Radiat. Transfer 83, 345–360 (2004).
    [CrossRef]
  34. P. Kluczynski, Å. M. Lindberg, and O. Axner, “Background signals in wavelength-modulation spectrometry with frequency-doubled diode-laser light. I. Theory,” Appl. Opt. 40, 783–793 (2001).
    [CrossRef]
  35. R. Arndt, “Analytical line shapes for Lorentzian signals broadened by modulation,” J. Appl. Phys. 36, 2522–2524 (1965).
    [CrossRef]
  36. H. Li, A. Farooq, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of temperature-dependent collisional-narrowing and broadening parameters of Ar-perturbed H2O transitions at 1391.7 and 1397.8 nm,” J. Quant. Spectrosc. Radiat. Transfer 109, 132–143 (2008).
    [CrossRef]
  37. C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of linestrength and temperature-dependent lineshape parameters of H2O-, CO2-, and N2-perturbed H2O transitions near 2474 and 2482 nm,” J. Quant. Spectrosc. Radiat. Transfer 130, 100–111 (2013).
    [CrossRef]
  38. C. S. Goldenstein, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Two-color absorption spectroscopy strategy for measuring the column density and path average temperature of the absorbing species in non-uniform gases,” Appl. Opt. 52, 7950–7962 (2013).
    [CrossRef]
  39. G. B. Rieker, “Wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Ph. D. dissertation (Stanford University, 2009).
  40. C. S. Goldenstein, R. M. Spearrin, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Wavelength-modulation spectroscopy near 1.4 μm for measurements of H2O and temperature in high-pressure and—temperature gases,” Meas. Sci. Technol. (in press).
  41. W. N. Heltsley, J. A. Snyder, A. J. Houle, D. F. Davidson, M. G. Mungal, and R. K. Hanson, “Design and characterization of the Stanford 6 inch expansion tube,” in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2006), paper AIAA 2006-4443.
  42. R. L. Trimpi, A preliminary theoretical study of the expansion tube, a new device for producing high-enthalpy short-duration Hypersonic Gas Flows Tech. Rep., (1962).
  43. V. A. Miller, M. Gamba, M. G. Mungal, and R. K. Hanson, “Secondary diaphragm thickness effects and improved pressure measurements in an expansion tube,” AIAA J. (in press).
  44. M. Gamba, V. A. Miller, M. G. Mungal, and R. K. Hanson, “Combustion characteristics of an inlet/supersonic combustor model,” in 50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition (American Institute of Aeronautics and Astronautics, 2012), paper AIAA 2012-0612.

2013 (4)

K. Sun, X. Chao, R. Sur, J. B. Jeffries, and R. K. Hanson, “Wavelength modulation diode laser absorption spectroscopy for high-pressure gas sensing,” Appl. Phys. B 110, 497–508 (2013).
[CrossRef]

K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
[CrossRef]

C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of linestrength and temperature-dependent lineshape parameters of H2O-, CO2-, and N2-perturbed H2O transitions near 2474 and 2482 nm,” J. Quant. Spectrosc. Radiat. Transfer 130, 100–111 (2013).
[CrossRef]

C. S. Goldenstein, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Two-color absorption spectroscopy strategy for measuring the column density and path average temperature of the absorbing species in non-uniform gases,” Appl. Opt. 52, 7950–7962 (2013).
[CrossRef]

2011 (2)

2010 (1)

L. S. Chang, J. B. Jeffries, and R. K. Hanson, “Mass flux sensing via tunable diode laser absorption of water vapor,” AIAA J. 48, 2687–2693 (2010).
[CrossRef]

2009 (3)

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

G. Hancock, J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker, “Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser,” Appl. Phys. Lett. 94, 201110 (2009).
[CrossRef]

G. B. Rieker, J. B. Jeffries, and R. K. Hanson, “Calibration-free wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Appl. Opt. 48, 5546–5560 (2009).
[CrossRef]

2008 (1)

H. Li, A. Farooq, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of temperature-dependent collisional-narrowing and broadening parameters of Ar-perturbed H2O transitions at 1391.7 and 1397.8 nm,” J. Quant. Spectrosc. Radiat. Transfer 109, 132–143 (2008).
[CrossRef]

2007 (4)

K. Duffin, A. J. McGettrick, W. Johnstone, G. Stewart, and D. G. Moodie, “Tunable diode-laser spectroscopy with wavelength modulation: a calibration-free approach to the recovery of absolute gas absorption line shapes,” J. Lightwave Technol. 25, 3114–3125 (2007).
[CrossRef]

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

X. Liu, J. B. Jeffries, and R. K. Hanson, “Measurements of spectral parameters of water-vapour transitions near 1388 and 1345 nm for accurate simulation of high-pressure absorption spectra,” Meas. Sci. Technol. 18, 1185–1194 (2007).
[CrossRef]

K. H. Lyle, J. B. Jeffries, and R. K. Hanson, “Diode-laser sensor for air-mass flux 1: design and wind tunnel validation,” AIAA J. 45, 2204–2212 (2007).
[CrossRef]

2006 (1)

2005 (4)

J. T. C. Liu, G. B. Rieker, J. B. Jeffries, M. R. Gruber, C. D. Carter, T. Mathur, and R. K. Hanson, “Near-infrared diode laser absorption diagnostic for temperature and water vapor in a scramjet combustor,” Appl. Opt. 44, 6701–6711 (2005).
[CrossRef]

T. R. Meyer, S. Roy, T. N. Anderson, R. P. Lucht, R. Barron-Jimenez, and J. R. Gord, “10 kHz detection of CO2 at 4.5 μm by using tunable diode-laser-based difference-frequency generation,” Opt. Lett. 30, 3087–3089 (2005).
[CrossRef]

V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
[CrossRef]

G. Wysocki, A. A. Kosterev, and F. K. Tittel, “Spectroscopic trace-gas sensor with rapidly scanned wavelengths of a pulsed quantum cascade laser for in situ NO monitoring of industrial exhaust systems,” Appl. Phys. B 80, 617–625 (2005).
[CrossRef]

2004 (1)

P. Kluczynski, Å. M. Lindberg, and O. Axner, “Wavelength modulation diode laser absorption signals from Doppler broadened absorption profiles,” J. Quant. Spectrosc. Radiat. Transfer 83, 345–360 (2004).
[CrossRef]

2002 (2)

R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
[CrossRef]

T. Fernholz, H. Teichert, and V. Ebert, “Digital, phase-sensitive detection for in situ diode-laser spectroscopy under rapidly changing transmission conditions,” Appl. Phys. B 75, 229–236 (2002).
[CrossRef]

2001 (1)

2000 (1)

S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, “Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines,” Proc. Combust. Inst. 28, 587–594 (2000).
[CrossRef]

1999 (2)

1998 (2)

J. Wolfrum, “Lasers in combustion: from basic theory to practical devices,” Proc. Combust. Inst. 27, 1–41 (1998).

M. G. Allen, “Diode laser absorption sensors for gas-dynamic and combustion flows,” Meas. Sci. Technol. 9, 545–562 (1998).
[CrossRef]

1996 (1)

P. Werle, “Spectroscopic trace gas analysis using semiconductor diode lasers,” Spectrochim. Acta, Part A 52, 805–822 (1996).
[CrossRef]

1993 (1)

1992 (2)

1988 (1)

1982 (1)

1981 (1)

J. Reid and D. Labrie, “Second-harmonic detection with tunable diode lasers—comparison of experiment and theory,” Appl. Phys. B 26, 203–210 (1981).
[CrossRef]

1965 (1)

R. Arndt, “Analytical line shapes for Lorentzian signals broadened by modulation,” J. Appl. Phys. 36, 2522–2524 (1965).
[CrossRef]

Allen, M. G.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
[CrossRef]

M. G. Allen, “Diode laser absorption sensors for gas-dynamic and combustion flows,” Meas. Sci. Technol. 9, 545–562 (1998).
[CrossRef]

Anderson, T. N.

Arndt, R.

R. Arndt, “Analytical line shapes for Lorentzian signals broadened by modulation,” J. Appl. Phys. 36, 2522–2524 (1965).
[CrossRef]

Axner, O.

Baer, D. S.

S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, “Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines,” Proc. Combust. Inst. 28, 587–594 (2000).
[CrossRef]

Bain, J. R. P.

Baldwin, J. A.

S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, “Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines,” Proc. Combust. Inst. 28, 587–594 (2000).
[CrossRef]

Barron-Jimenez, R.

Bomse, D. S.

Bonnell, L. J.

Carter, C. D.

Cassidy, D. T.

Caswell, A. W.

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

Chang, L. S.

L. S. Chang, J. B. Jeffries, and R. K. Hanson, “Mass flux sensing via tunable diode laser absorption of water vapor,” AIAA J. 48, 2687–2693 (2010).
[CrossRef]

Chao, X.

K. Sun, X. Chao, R. Sur, J. B. Jeffries, and R. K. Hanson, “Wavelength modulation diode laser absorption spectroscopy for high-pressure gas sensing,” Appl. Phys. B 110, 497–508 (2013).
[CrossRef]

K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
[CrossRef]

Davidson, D. F.

W. N. Heltsley, J. A. Snyder, A. J. Houle, D. F. Davidson, M. G. Mungal, and R. K. Hanson, “Design and characterization of the Stanford 6 inch expansion tube,” in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2006), paper AIAA 2006-4443.

Duffin, K.

Ebert, V.

V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
[CrossRef]

T. Fernholz, H. Teichert, and V. Ebert, “Digital, phase-sensitive detection for in situ diode-laser spectroscopy under rapidly changing transmission conditions,” Appl. Phys. B 75, 229–236 (2002).
[CrossRef]

Farooq, A.

H. Li, A. Farooq, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of temperature-dependent collisional-narrowing and broadening parameters of Ar-perturbed H2O transitions at 1391.7 and 1397.8 nm,” J. Quant. Spectrosc. Radiat. Transfer 109, 132–143 (2008).
[CrossRef]

Fernholz, T.

T. Fernholz, H. Teichert, and V. Ebert, “Digital, phase-sensitive detection for in situ diode-laser spectroscopy under rapidly changing transmission conditions,” Appl. Phys. B 75, 229–236 (2002).
[CrossRef]

Gamba, M.

V. A. Miller, M. Gamba, M. G. Mungal, and R. K. Hanson, “Secondary diaphragm thickness effects and improved pressure measurements in an expansion tube,” AIAA J. (in press).

M. Gamba, V. A. Miller, M. G. Mungal, and R. K. Hanson, “Combustion characteristics of an inlet/supersonic combustor model,” in 50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition (American Institute of Aeronautics and Astronautics, 2012), paper AIAA 2012-0612.

Goldenstein, C. S.

K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
[CrossRef]

C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of linestrength and temperature-dependent lineshape parameters of H2O-, CO2-, and N2-perturbed H2O transitions near 2474 and 2482 nm,” J. Quant. Spectrosc. Radiat. Transfer 130, 100–111 (2013).
[CrossRef]

C. S. Goldenstein, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Two-color absorption spectroscopy strategy for measuring the column density and path average temperature of the absorbing species in non-uniform gases,” Appl. Opt. 52, 7950–7962 (2013).
[CrossRef]

C. S. Goldenstein, R. M. Spearrin, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Wavelength-modulation spectroscopy near 1.4 μm for measurements of H2O and temperature in high-pressure and—temperature gases,” Meas. Sci. Technol. (in press).

Gord, J. R.

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

T. R. Meyer, S. Roy, T. N. Anderson, R. P. Lucht, R. Barron-Jimenez, and J. R. Gord, “10 kHz detection of CO2 at 4.5 μm by using tunable diode-laser-based difference-frequency generation,” Opt. Lett. 30, 3087–3089 (2005).
[CrossRef]

Green, B. D.

R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
[CrossRef]

Gruber, M. R.

Hagen, C. L.

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

Hancock, G.

G. Hancock, J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker, “Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser,” Appl. Phys. Lett. 94, 201110 (2009).
[CrossRef]

Hanson, R. K.

C. S. Goldenstein, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Two-color absorption spectroscopy strategy for measuring the column density and path average temperature of the absorbing species in non-uniform gases,” Appl. Opt. 52, 7950–7962 (2013).
[CrossRef]

C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of linestrength and temperature-dependent lineshape parameters of H2O-, CO2-, and N2-perturbed H2O transitions near 2474 and 2482 nm,” J. Quant. Spectrosc. Radiat. Transfer 130, 100–111 (2013).
[CrossRef]

K. Sun, X. Chao, R. Sur, J. B. Jeffries, and R. K. Hanson, “Wavelength modulation diode laser absorption spectroscopy for high-pressure gas sensing,” Appl. Phys. B 110, 497–508 (2013).
[CrossRef]

K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
[CrossRef]

R. K. Hanson, “Applications of quantitative laser sensors to kinetics, propulsion and practical energy systems,” Proc. Combust. Inst. 33, 1–40 (2011).
[CrossRef]

L. S. Chang, J. B. Jeffries, and R. K. Hanson, “Mass flux sensing via tunable diode laser absorption of water vapor,” AIAA J. 48, 2687–2693 (2010).
[CrossRef]

G. B. Rieker, J. B. Jeffries, and R. K. Hanson, “Calibration-free wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Appl. Opt. 48, 5546–5560 (2009).
[CrossRef]

H. Li, A. Farooq, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of temperature-dependent collisional-narrowing and broadening parameters of Ar-perturbed H2O transitions at 1391.7 and 1397.8 nm,” J. Quant. Spectrosc. Radiat. Transfer 109, 132–143 (2008).
[CrossRef]

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

X. Liu, J. B. Jeffries, and R. K. Hanson, “Measurements of spectral parameters of water-vapour transitions near 1388 and 1345 nm for accurate simulation of high-pressure absorption spectra,” Meas. Sci. Technol. 18, 1185–1194 (2007).
[CrossRef]

K. H. Lyle, J. B. Jeffries, and R. K. Hanson, “Diode-laser sensor for air-mass flux 1: design and wind tunnel validation,” AIAA J. 45, 2204–2212 (2007).
[CrossRef]

H. Li, G. B. Rieker, X. Liu, J. B. Jeffries, and R. K. Hanson, “Extension of wavelength-modulation spectroscopy to large modulation depth for diode laser absorption measurements in high-pressure gases,” Appl. Opt. 45, 1052–1061 (2006).
[CrossRef]

J. T. C. Liu, G. B. Rieker, J. B. Jeffries, M. R. Gruber, C. D. Carter, T. Mathur, and R. K. Hanson, “Near-infrared diode laser absorption diagnostic for temperature and water vapor in a scramjet combustor,” Appl. Opt. 44, 6701–6711 (2005).
[CrossRef]

S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, “Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines,” Proc. Combust. Inst. 28, 587–594 (2000).
[CrossRef]

L. C. Philippe and R. K. Hanson, “Laser diode wavelength-modulation spectroscopy for simultaneous measurement of temperature, pressure, and velocity in shock-heated oxygen flows,” Appl. Opt. 32, 6090–6103 (1993).
[CrossRef]

M. Gamba, V. A. Miller, M. G. Mungal, and R. K. Hanson, “Combustion characteristics of an inlet/supersonic combustor model,” in 50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition (American Institute of Aeronautics and Astronautics, 2012), paper AIAA 2012-0612.

C. S. Goldenstein, R. M. Spearrin, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Wavelength-modulation spectroscopy near 1.4 μm for measurements of H2O and temperature in high-pressure and—temperature gases,” Meas. Sci. Technol. (in press).

W. N. Heltsley, J. A. Snyder, A. J. Houle, D. F. Davidson, M. G. Mungal, and R. K. Hanson, “Design and characterization of the Stanford 6 inch expansion tube,” in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2006), paper AIAA 2006-4443.

C. L. Strand and R. K. Hanson, “Thermometry and velocimetry in supersonic flows via scanned wavelength-modulation absorption spectroscopy,” in 47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2011), paper AIAA 2011-5600.

V. A. Miller, M. Gamba, M. G. Mungal, and R. K. Hanson, “Secondary diaphragm thickness effects and improved pressure measurements in an expansion tube,” AIAA J. (in press).

Heltsley, W. N.

W. N. Heltsley, J. A. Snyder, A. J. Houle, D. F. Davidson, M. G. Mungal, and R. K. Hanson, “Design and characterization of the Stanford 6 inch expansion tube,” in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2006), paper AIAA 2006-4443.

Houle, A. J.

W. N. Heltsley, J. A. Snyder, A. J. Houle, D. F. Davidson, M. G. Mungal, and R. K. Hanson, “Design and characterization of the Stanford 6 inch expansion tube,” in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2006), paper AIAA 2006-4443.

Jeffries, J. B.

K. Sun, X. Chao, R. Sur, J. B. Jeffries, and R. K. Hanson, “Wavelength modulation diode laser absorption spectroscopy for high-pressure gas sensing,” Appl. Phys. B 110, 497–508 (2013).
[CrossRef]

C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of linestrength and temperature-dependent lineshape parameters of H2O-, CO2-, and N2-perturbed H2O transitions near 2474 and 2482 nm,” J. Quant. Spectrosc. Radiat. Transfer 130, 100–111 (2013).
[CrossRef]

C. S. Goldenstein, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Two-color absorption spectroscopy strategy for measuring the column density and path average temperature of the absorbing species in non-uniform gases,” Appl. Opt. 52, 7950–7962 (2013).
[CrossRef]

K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
[CrossRef]

L. S. Chang, J. B. Jeffries, and R. K. Hanson, “Mass flux sensing via tunable diode laser absorption of water vapor,” AIAA J. 48, 2687–2693 (2010).
[CrossRef]

G. B. Rieker, J. B. Jeffries, and R. K. Hanson, “Calibration-free wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Appl. Opt. 48, 5546–5560 (2009).
[CrossRef]

H. Li, A. Farooq, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of temperature-dependent collisional-narrowing and broadening parameters of Ar-perturbed H2O transitions at 1391.7 and 1397.8 nm,” J. Quant. Spectrosc. Radiat. Transfer 109, 132–143 (2008).
[CrossRef]

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

X. Liu, J. B. Jeffries, and R. K. Hanson, “Measurements of spectral parameters of water-vapour transitions near 1388 and 1345 nm for accurate simulation of high-pressure absorption spectra,” Meas. Sci. Technol. 18, 1185–1194 (2007).
[CrossRef]

K. H. Lyle, J. B. Jeffries, and R. K. Hanson, “Diode-laser sensor for air-mass flux 1: design and wind tunnel validation,” AIAA J. 45, 2204–2212 (2007).
[CrossRef]

H. Li, G. B. Rieker, X. Liu, J. B. Jeffries, and R. K. Hanson, “Extension of wavelength-modulation spectroscopy to large modulation depth for diode laser absorption measurements in high-pressure gases,” Appl. Opt. 45, 1052–1061 (2006).
[CrossRef]

J. T. C. Liu, G. B. Rieker, J. B. Jeffries, M. R. Gruber, C. D. Carter, T. Mathur, and R. K. Hanson, “Near-infrared diode laser absorption diagnostic for temperature and water vapor in a scramjet combustor,” Appl. Opt. 44, 6701–6711 (2005).
[CrossRef]

C. S. Goldenstein, R. M. Spearrin, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Wavelength-modulation spectroscopy near 1.4 μm for measurements of H2O and temperature in high-pressure and—temperature gases,” Meas. Sci. Technol. (in press).

Jenkins, T. P.

S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, “Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines,” Proc. Combust. Inst. 28, 587–594 (2000).
[CrossRef]

Johnstone, W.

Kakuho, A.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

Kindle, H. S.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

Kluczynski, P.

Kolb, T.

V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
[CrossRef]

Kosterev, A. A.

G. Wysocki, A. A. Kosterev, and F. K. Tittel, “Spectroscopic trace-gas sensor with rapidly scanned wavelengths of a pulsed quantum cascade laser for in situ NO monitoring of industrial exhaust systems,” Appl. Phys. B 80, 617–625 (2005).
[CrossRef]

Kranendonk, L. A.

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

Labrie, D.

J. Reid and D. Labrie, “Second-harmonic detection with tunable diode lasers—comparison of experiment and theory,” Appl. Phys. B 26, 203–210 (1981).
[CrossRef]

Lengden, M.

Li, H.

H. Li, A. Farooq, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of temperature-dependent collisional-narrowing and broadening parameters of Ar-perturbed H2O transitions at 1391.7 and 1397.8 nm,” J. Quant. Spectrosc. Radiat. Transfer 109, 132–143 (2008).
[CrossRef]

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

H. Li, G. B. Rieker, X. Liu, J. B. Jeffries, and R. K. Hanson, “Extension of wavelength-modulation spectroscopy to large modulation depth for diode laser absorption measurements in high-pressure gases,” Appl. Opt. 45, 1052–1061 (2006).
[CrossRef]

Lindberg, Å. M.

P. Kluczynski, Å. M. Lindberg, and O. Axner, “Wavelength modulation diode laser absorption signals from Doppler broadened absorption profiles,” J. Quant. Spectrosc. Radiat. Transfer 83, 345–360 (2004).
[CrossRef]

P. Kluczynski, Å. M. Lindberg, and O. Axner, “Background signals in wavelength-modulation spectrometry with frequency-doubled diode-laser light. I. Theory,” Appl. Opt. 40, 783–793 (2001).
[CrossRef]

Liu, J. T. C.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

J. T. C. Liu, G. B. Rieker, J. B. Jeffries, M. R. Gruber, C. D. Carter, T. Mathur, and R. K. Hanson, “Near-infrared diode laser absorption diagnostic for temperature and water vapor in a scramjet combustor,” Appl. Opt. 44, 6701–6711 (2005).
[CrossRef]

Liu, X.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

X. Liu, J. B. Jeffries, and R. K. Hanson, “Measurements of spectral parameters of water-vapour transitions near 1388 and 1345 nm for accurate simulation of high-pressure absorption spectra,” Meas. Sci. Technol. 18, 1185–1194 (2007).
[CrossRef]

H. Li, G. B. Rieker, X. Liu, J. B. Jeffries, and R. K. Hanson, “Extension of wavelength-modulation spectroscopy to large modulation depth for diode laser absorption measurements in high-pressure gases,” Appl. Opt. 45, 1052–1061 (2006).
[CrossRef]

Lucht, R. P.

Lyle, K. H.

K. H. Lyle, J. B. Jeffries, and R. K. Hanson, “Diode-laser sensor for air-mass flux 1: design and wind tunnel validation,” AIAA J. 45, 2204–2212 (2007).
[CrossRef]

Mathur, T.

Matsuura, T.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

McGettrick, A. J.

Meyer, T. R.

Miller, V. A.

V. A. Miller, M. Gamba, M. G. Mungal, and R. K. Hanson, “Secondary diaphragm thickness effects and improved pressure measurements in an expansion tube,” AIAA J. (in press).

M. Gamba, V. A. Miller, M. G. Mungal, and R. K. Hanson, “Combustion characteristics of an inlet/supersonic combustor model,” in 50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition (American Institute of Aeronautics and Astronautics, 2012), paper AIAA 2012-0612.

Moodie, D. G.

Mulhall, P. A.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

Mungal, M. G.

V. A. Miller, M. Gamba, M. G. Mungal, and R. K. Hanson, “Secondary diaphragm thickness effects and improved pressure measurements in an expansion tube,” AIAA J. (in press).

M. Gamba, V. A. Miller, M. G. Mungal, and R. K. Hanson, “Combustion characteristics of an inlet/supersonic combustor model,” in 50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition (American Institute of Aeronautics and Astronautics, 2012), paper AIAA 2012-0612.

W. N. Heltsley, J. A. Snyder, A. J. Houle, D. F. Davidson, M. G. Mungal, and R. K. Hanson, “Design and characterization of the Stanford 6 inch expansion tube,” in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2006), paper AIAA 2006-4443.

Naper, R.

R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
[CrossRef]

Neuroth, C. T.

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

Peverall, R.

G. Hancock, J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker, “Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser,” Appl. Phys. Lett. 94, 201110 (2009).
[CrossRef]

Philippe, L. C.

Reid, J.

D. T. Cassidy and J. Reid, “Atmospheric pressure monitoring of trace gases using tunable diode lasers,” Appl. Opt. 21, 1185–1190 (1982).
[CrossRef]

J. Reid and D. Labrie, “Second-harmonic detection with tunable diode lasers—comparison of experiment and theory,” Appl. Phys. B 26, 203–210 (1981).
[CrossRef]

Rieker, G. B.

G. B. Rieker, J. B. Jeffries, and R. K. Hanson, “Calibration-free wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Appl. Opt. 48, 5546–5560 (2009).
[CrossRef]

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

H. Li, G. B. Rieker, X. Liu, J. B. Jeffries, and R. K. Hanson, “Extension of wavelength-modulation spectroscopy to large modulation depth for diode laser absorption measurements in high-pressure gases,” Appl. Opt. 45, 1052–1061 (2006).
[CrossRef]

J. T. C. Liu, G. B. Rieker, J. B. Jeffries, M. R. Gruber, C. D. Carter, T. Mathur, and R. K. Hanson, “Near-infrared diode laser absorption diagnostic for temperature and water vapor in a scramjet combustor,” Appl. Opt. 44, 6701–6711 (2005).
[CrossRef]

G. B. Rieker, “Wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Ph. D. dissertation (Stanford University, 2009).

Ritchie, G. A. D.

G. Hancock, J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker, “Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser,” Appl. Phys. Lett. 94, 201110 (2009).
[CrossRef]

Roy, S.

Ruxton, K.

Sanders, S. T.

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, “Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines,” Proc. Combust. Inst. 28, 587–594 (2000).
[CrossRef]

Schultz, I. A.

C. S. Goldenstein, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Two-color absorption spectroscopy strategy for measuring the column density and path average temperature of the absorbing species in non-uniform gases,” Appl. Opt. 52, 7950–7962 (2013).
[CrossRef]

C. S. Goldenstein, R. M. Spearrin, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Wavelength-modulation spectroscopy near 1.4 μm for measurements of H2O and temperature in high-pressure and—temperature gases,” Meas. Sci. Technol. (in press).

Seifert, H.

V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
[CrossRef]

Seiter, M.

Sholes, K. R.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

Shouse, D. T.

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

Sigrist, M. W.

Silver, J. A.

Snyder, J. A.

W. N. Heltsley, J. A. Snyder, A. J. Houle, D. F. Davidson, M. G. Mungal, and R. K. Hanson, “Design and characterization of the Stanford 6 inch expansion tube,” in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2006), paper AIAA 2006-4443.

Spearrin, R. M.

C. S. Goldenstein, R. M. Spearrin, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Wavelength-modulation spectroscopy near 1.4 μm for measurements of H2O and temperature in high-pressure and—temperature gases,” Meas. Sci. Technol. (in press).

Stafford-Evans, J.

R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
[CrossRef]

Stanton, A. C.

Stewart, G.

Strand, C. L.

C. L. Strand and R. K. Hanson, “Thermometry and velocimetry in supersonic flows via scanned wavelength-modulation absorption spectroscopy,” in 47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2011), paper AIAA 2011-5600.

Strauch, P.

V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
[CrossRef]

Sun, K.

K. Sun, X. Chao, R. Sur, J. B. Jeffries, and R. K. Hanson, “Wavelength modulation diode laser absorption spectroscopy for high-pressure gas sensing,” Appl. Phys. B 110, 497–508 (2013).
[CrossRef]

K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
[CrossRef]

Sur, R.

K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
[CrossRef]

K. Sun, X. Chao, R. Sur, J. B. Jeffries, and R. K. Hanson, “Wavelength modulation diode laser absorption spectroscopy for high-pressure gas sensing,” Appl. Phys. B 110, 497–508 (2013).
[CrossRef]

Takatani, S.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

Teichert, H.

V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
[CrossRef]

T. Fernholz, H. Teichert, and V. Ebert, “Digital, phase-sensitive detection for in situ diode-laser spectroscopy under rapidly changing transmission conditions,” Appl. Phys. B 75, 229–236 (2002).
[CrossRef]

Tittel, F. K.

G. Wysocki, A. A. Kosterev, and F. K. Tittel, “Spectroscopic trace-gas sensor with rapidly scanned wavelengths of a pulsed quantum cascade laser for in situ NO monitoring of industrial exhaust systems,” Appl. Phys. B 80, 617–625 (2005).
[CrossRef]

Trimpi, R. L.

R. L. Trimpi, A preliminary theoretical study of the expansion tube, a new device for producing high-enthalpy short-duration Hypersonic Gas Flows Tech. Rep., (1962).

van Helden, J. H.

G. Hancock, J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker, “Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser,” Appl. Phys. Lett. 94, 201110 (2009).
[CrossRef]

Wainner, R. T.

R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
[CrossRef]

Walker, R. J.

G. Hancock, J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker, “Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser,” Appl. Phys. Lett. 94, 201110 (2009).
[CrossRef]

Wehe, S. D.

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

Werle, P.

P. Werle, “Spectroscopic trace gas analysis using semiconductor diode lasers,” Spectrochim. Acta, Part A 52, 805–822 (1996).
[CrossRef]

White, M. A.

R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
[CrossRef]

Wolfrum, J.

V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
[CrossRef]

J. Wolfrum, “Lasers in combustion: from basic theory to practical devices,” Proc. Combust. Inst. 27, 1–41 (1998).

Wysocki, G.

G. Wysocki, A. A. Kosterev, and F. K. Tittel, “Spectroscopic trace-gas sensor with rapidly scanned wavelengths of a pulsed quantum cascade laser for in situ NO monitoring of industrial exhaust systems,” Appl. Phys. B 80, 617–625 (2005).
[CrossRef]

AIAA J. (2)

L. S. Chang, J. B. Jeffries, and R. K. Hanson, “Mass flux sensing via tunable diode laser absorption of water vapor,” AIAA J. 48, 2687–2693 (2010).
[CrossRef]

K. H. Lyle, J. B. Jeffries, and R. K. Hanson, “Diode-laser sensor for air-mass flux 1: design and wind tunnel validation,” AIAA J. 45, 2204–2212 (2007).
[CrossRef]

Appl. Opt. (12)

H. Li, G. B. Rieker, X. Liu, J. B. Jeffries, and R. K. Hanson, “Extension of wavelength-modulation spectroscopy to large modulation depth for diode laser absorption measurements in high-pressure gases,” Appl. Opt. 45, 1052–1061 (2006).
[CrossRef]

G. B. Rieker, J. B. Jeffries, and R. K. Hanson, “Calibration-free wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Appl. Opt. 48, 5546–5560 (2009).
[CrossRef]

C. S. Goldenstein, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Two-color absorption spectroscopy strategy for measuring the column density and path average temperature of the absorbing species in non-uniform gases,” Appl. Opt. 52, 7950–7962 (2013).
[CrossRef]

D. T. Cassidy and J. Reid, “Atmospheric pressure monitoring of trace gases using tunable diode lasers,” Appl. Opt. 21, 1185–1190 (1982).
[CrossRef]

J. A. Silver, “Frequency-modulation spectroscopy for trace species detection: theory and comparison among experimental methods,” Appl. Opt. 31, 707–717 (1992).
[CrossRef]

D. S. Bomse, A. C. Stanton, and J. A. Silver, “Frequency modulation and wavelength modulation spectroscopies: comparison of experimental methods using a lead-salt diode laser,” Appl. Opt. 31, 718–731 (1992).
[CrossRef]

L. C. Philippe and R. K. Hanson, “Laser diode wavelength-modulation spectroscopy for simultaneous measurement of temperature, pressure, and velocity in shock-heated oxygen flows,” Appl. Opt. 32, 6090–6103 (1993).
[CrossRef]

M. Seiter and M. W. Sigrist, “On-line multicomponent trace-gas analysis with a broadly tunable pulsed difference-frequency laser spectrometer,” Appl. Opt. 38, 4691–4698 (1999).
[CrossRef]

P. Kluczynski and O. Axner, “Theoretical description based on Fourier analysis of wavelength-modulation spectrometry in terms of analytical and background signals,” Appl. Opt. 38, 5803–5815 (1999).
[CrossRef]

P. Kluczynski, Å. M. Lindberg, and O. Axner, “Background signals in wavelength-modulation spectrometry with frequency-doubled diode-laser light. I. Theory,” Appl. Opt. 40, 783–793 (2001).
[CrossRef]

D. T. Cassidy and L. J. Bonnell, “Trace gas detection with short-external-cavity InGaAsP diode laser transmitter modules operating at 1.58 μm,” Appl. Opt. 27, 2688–2693 (1988).
[CrossRef]

J. T. C. Liu, G. B. Rieker, J. B. Jeffries, M. R. Gruber, C. D. Carter, T. Mathur, and R. K. Hanson, “Near-infrared diode laser absorption diagnostic for temperature and water vapor in a scramjet combustor,” Appl. Opt. 44, 6701–6711 (2005).
[CrossRef]

Appl. Phys. B (5)

J. Reid and D. Labrie, “Second-harmonic detection with tunable diode lasers—comparison of experiment and theory,” Appl. Phys. B 26, 203–210 (1981).
[CrossRef]

K. Sun, X. Chao, R. Sur, J. B. Jeffries, and R. K. Hanson, “Wavelength modulation diode laser absorption spectroscopy for high-pressure gas sensing,” Appl. Phys. B 110, 497–508 (2013).
[CrossRef]

R. T. Wainner, B. D. Green, M. G. Allen, M. A. White, J. Stafford-Evans, and R. Naper, “Handheld, battery-powered near-IR TDL sensor for stand-off detection of gas and vapor plumes,” Appl. Phys. B 75, 249–254 (2002).
[CrossRef]

T. Fernholz, H. Teichert, and V. Ebert, “Digital, phase-sensitive detection for in situ diode-laser spectroscopy under rapidly changing transmission conditions,” Appl. Phys. B 75, 229–236 (2002).
[CrossRef]

G. Wysocki, A. A. Kosterev, and F. K. Tittel, “Spectroscopic trace-gas sensor with rapidly scanned wavelengths of a pulsed quantum cascade laser for in situ NO monitoring of industrial exhaust systems,” Appl. Phys. B 80, 617–625 (2005).
[CrossRef]

Appl. Phys. Lett. (1)

G. Hancock, J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker, “Direct and wavelength modulation spectroscopy using a cw external cavity quantum cascade laser,” Appl. Phys. Lett. 94, 201110 (2009).
[CrossRef]

J. Appl. Phys. (1)

R. Arndt, “Analytical line shapes for Lorentzian signals broadened by modulation,” J. Appl. Phys. 36, 2522–2524 (1965).
[CrossRef]

J. Lightwave Technol. (2)

J. Propul. Power (1)

L. A. Kranendonk, A. W. Caswell, C. L. Hagen, C. T. Neuroth, D. T. Shouse, J. R. Gord, and S. T. Sanders, “Temperature measurements in a gas-turbine-combustor sector rig using swept-wavelength absorption spectroscopy,” J. Propul. Power 25, 859–863 (2009).
[CrossRef]

J. Quant. Spectrosc. Radiat. Transfer (3)

H. Li, A. Farooq, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of temperature-dependent collisional-narrowing and broadening parameters of Ar-perturbed H2O transitions at 1391.7 and 1397.8 nm,” J. Quant. Spectrosc. Radiat. Transfer 109, 132–143 (2008).
[CrossRef]

C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Diode laser measurements of linestrength and temperature-dependent lineshape parameters of H2O-, CO2-, and N2-perturbed H2O transitions near 2474 and 2482 nm,” J. Quant. Spectrosc. Radiat. Transfer 130, 100–111 (2013).
[CrossRef]

P. Kluczynski, Å. M. Lindberg, and O. Axner, “Wavelength modulation diode laser absorption signals from Doppler broadened absorption profiles,” J. Quant. Spectrosc. Radiat. Transfer 83, 345–360 (2004).
[CrossRef]

Meas. Sci. Technol. (3)

M. G. Allen, “Diode laser absorption sensors for gas-dynamic and combustion flows,” Meas. Sci. Technol. 9, 545–562 (1998).
[CrossRef]

K. Sun, X. Chao, R. Sur, C. S. Goldenstein, J. B. Jeffries, and R. K. Hanson, “Analysis of calibration-free wavelength-scanned modulation spectroscopy for practical gas sensing using tunable diode lasers,” Meas. Sci. Technol. 24, 125203 (2013).
[CrossRef]

X. Liu, J. B. Jeffries, and R. K. Hanson, “Measurements of spectral parameters of water-vapour transitions near 1388 and 1345 nm for accurate simulation of high-pressure absorption spectra,” Meas. Sci. Technol. 18, 1185–1194 (2007).
[CrossRef]

Opt. Lett. (1)

Proc. Combust. Inst. (5)

R. K. Hanson, “Applications of quantitative laser sensors to kinetics, propulsion and practical energy systems,” Proc. Combust. Inst. 33, 1–40 (2011).
[CrossRef]

S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, “Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines,” Proc. Combust. Inst. 28, 587–594 (2000).
[CrossRef]

V. Ebert, H. Teichert, P. Strauch, T. Kolb, H. Seifert, and J. Wolfrum, “Sensitive in situ detection of CO and O2 in a rotary kiln-based hazardous waste incinerator using 760 nm and new 2.3 μm diode lasers,” Proc. Combust. Inst. 30, 1611–1618 (2005).
[CrossRef]

G. B. Rieker, H. Li, X. Liu, J. T. C. Liu, J. B. Jeffries, R. K. Hanson, M. G. Allen, S. D. Wehe, P. A. Mulhall, H. S. Kindle, A. Kakuho, K. R. Sholes, T. Matsuura, and S. Takatani, “Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor,” Proc. Combust. Inst. 31, 3041–3049 (2007).
[CrossRef]

J. Wolfrum, “Lasers in combustion: from basic theory to practical devices,” Proc. Combust. Inst. 27, 1–41 (1998).

Spectrochim. Acta, Part A (1)

P. Werle, “Spectroscopic trace gas analysis using semiconductor diode lasers,” Spectrochim. Acta, Part A 52, 805–822 (1996).
[CrossRef]

Other (7)

C. L. Strand and R. K. Hanson, “Thermometry and velocimetry in supersonic flows via scanned wavelength-modulation absorption spectroscopy,” in 47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2011), paper AIAA 2011-5600.

G. B. Rieker, “Wavelength-modulation spectroscopy for measurements of gas temperature and concentration in harsh environments,” Ph. D. dissertation (Stanford University, 2009).

C. S. Goldenstein, R. M. Spearrin, I. A. Schultz, J. B. Jeffries, and R. K. Hanson, “Wavelength-modulation spectroscopy near 1.4 μm for measurements of H2O and temperature in high-pressure and—temperature gases,” Meas. Sci. Technol. (in press).

W. N. Heltsley, J. A. Snyder, A. J. Houle, D. F. Davidson, M. G. Mungal, and R. K. Hanson, “Design and characterization of the Stanford 6 inch expansion tube,” in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (American Institute of Aeronautics and Astronautics, 2006), paper AIAA 2006-4443.

R. L. Trimpi, A preliminary theoretical study of the expansion tube, a new device for producing high-enthalpy short-duration Hypersonic Gas Flows Tech. Rep., (1962).

V. A. Miller, M. Gamba, M. G. Mungal, and R. K. Hanson, “Secondary diaphragm thickness effects and improved pressure measurements in an expansion tube,” AIAA J. (in press).

M. Gamba, V. A. Miller, M. G. Mungal, and R. K. Hanson, “Combustion characteristics of an inlet/supersonic combustor model,” in 50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition (American Institute of Aeronautics and Astronautics, 2012), paper AIAA 2012-0612.

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Figures (11)

Fig. 1.
Fig. 1.

Typical experimental setup used for scanned-WMS-nf/1f experiments.

Fig. 2.
Fig. 2.

Examples of (a) simulated laser intensities, (b) laser wavenumber, (c) absorbance, and (d) scanned-WMS-2f/1f signals as a function of time for a single scan period. In (c), the absorbance at v(t) repeatedly reaches the peak absorbance (i.e., 0.10) because the scanned and modulated optical frequency repeatedly passes over the transition linecenter. In (d), the magnitude and shape of the scanned-WMS-2f/1f spectrum varies between the intensity up-scan and down-scan because the phase shift between the laser intensity and wavenumber is not equal to π.

Fig. 3.
Fig. 3.

Flow chart for illustrating scanned-WMS-nf/1f spectral-fitting routine.

Fig. 4.
Fig. 4.

(a) Simulated peak-normalized-absorbance, (b) scanned-WMS-2f/1f, (c) 3f/1f, and (d) 4f/1f spectra for an optically thin Voigt lineshape with three values of Δvc (Lorentzian to Doppler width ratio of 0.5, 1, and 2) and a fixed A. For scanned-WMS-nf/1f simulations, a1,M=0.075cm1. Changing Δvc significantly alters the shape of the absorbance and scanned-WMS-nf/1f spectra away from vo.

Fig. 5.
Fig. 5.

Scanned-DA and scanned-WMS-2f/1f spectra for a single-scan measurement at 1 kHz. Both scanned-DA and scanned-WMS-2f/1f fits yield the same A and Δvc within uncertainty.

Fig. 6.
Fig. 6.

Simplified experimental setup used in expansion tube testing.

Fig. 7.
Fig. 7.

Scanned-WMS-2f/1f signals for a single expansion tube test with TDLs near (a) 1391.7 nm and (b) 1343.3 nm. The WMS-2f/1f signals corresponding to a single half-scan (up-scan or down-scan) were isolated from the time history and simulated signals were least-squares fit to each spectrum to infer gas conditions.

Fig. 8.
Fig. 8.

Measured gas temperature, bulk speed, H2O mole fraction, and Δvc for transition near 7185.59cm1 (left) and measured pressure (right) for a single expansion tube test. Time equal to zero denotes the arrival of the test gas at the leading TDLAS LOS located 72.5 mm from the leading edge of the combustor (FLE). Measured values agree well with expected values denoted by solid lines. Scanned-WMS pressure measurements are only shown from 0.125–0.8 ms due to the presence of helium in the contact surfaces that arrive at the beginning and end of the test time. Beyond approximately 0.35 ms, the pressure transducer measurements are shown as constant at the nominally steady value due to the onset of high-frequency and high-amplitude noise that has since been mitigated [43].

Fig. 9.
Fig. 9.

(a), (b) Peak WMS-nf and nf/1f signals near linecenter and (c) sensitivity of scanned-WMS-nf/1f spectra to A and Δvc as a function of m. Results are shown for an H2O transition described by a Voigt profile with a peak absorbance of 0.1, a L/D=1, and a FWHM=0.065cm1.

Fig. 10.
Fig. 10.

(a), (b) Examples of raw (undistorted) and distorted absorbance and (c) scanned-WMS-2f/1f spectra. Low-frequency distortion (b) significantly alters raw absorbance spectrum and its best-fit, but the scanned-WMS-2f/1f spectrum and its best-fit (c) are only weakly affected by the distortion.

Fig. 11.
Fig. 11.

Distortion-induced error in scanned-WMS-2f/1f spectra as a function of η for a distortion signal with an amplitude of 1% of the peak raw-absorbance. Each curve represents a different value of modulation index. Error in scanned-WMS-2f/1f spectra goes to zero as η goes to zero and infinity.

Tables (1)

Tables Icon

Table 1. Comparison between Measured and Simulated Nominally Steady Gas Parameters for an Expansion Tube Test

Equations (9)

Equations on this page are rendered with MathJax. Learn more.

Io(t)=Io,S(t)+Io,M(t),
Io,S(t)=I¯o[12+i1,Ssin(ωSt+ϕ1,S)+i2,Ssin(2ωSt+ϕ2,S)],
Io,M(t)=I¯o[12+i1,Msin(ωMt+ϕ1,M)+i2,Msin(2ωMt+ϕ2,M)].
v(t)=v¯L+vS(t)+vM(t),
vS(t)=a1,Ssin(ωSt+ψ1,S)+a2,Ssin(2ωSt+ψ2,S),
vM(t)=a1,Msin(ωMt+ψ1,M)+a2,Msin(2ωMt+ψ2,M),
It(t)=Io(t)exp[jAjϕj(v(t),T,P,χ)],
Ajα(v)dv=0LSj(T)Pidl.
Snf/1f(t)=Xnf2(t)+Ynf2(t)/X1f2(t)+Y1f2(t)=f(A,ϕ,laser dynamics),

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