Abstract

We study the accuracy and uncertainty of single-shot nonresonant laser-induced thermal acoustics measurements of the speed of sound and the thermal diffusivity in unseeded atmospheric air from electrostrictive gratings as a function of the laser power settings. For low pump energies, the measured speed of sound is too low, which is due to the influence of noise on the numerical data analysis scheme. For pump energies comparable to and higher than the breakdown energy of the gas, the measured speed of sound is too high. This is an effect of leaving the acoustic limit, and instead creating finite-amplitude density perturbations. The measured thermal diffusivity is too large for high noise levels but it decreases below the predicted value for high pump energies. The pump energy where the error is minimal coincides for the speed of sound and for the thermal diffusivity measurements. The errors at this minimum are 0.03% and 1%, respectively. The uncertainties for the speed of sound and the thermal diffusivity decrease monotonically with signal intensity to 0.25% and 5%, respectively.

© 2000 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. E. B. Cummings, I. A. Leyva, H. G. Hornung, “Laser-induced thermal acoustics (LITA) signals from finite beams,” Appl. Opt. 34, 3290–3302 (1995).
    [CrossRef] [PubMed]
  2. S. Schlamp, E. B. Cummings, H. G. Hornung, “beam misalignments and fluid velocities in laser-induced thermal acoustics (LITA),” Appl. Opt. 38, 5724–5733 (1999).
    [CrossRef]
  3. W. H. Press, Numerical Recipes in C: the Art of Scientific Computing (Cambridge U. Press, New York, 1988).
  4. A. Stampanoni-Panariello, B. Hemmerling, W. Hubschmid, “Temperature measurements in gases using laser-inducedelectrostrictive gratings,” Appl. Phys. B 67(1), 125–130 (1998).
  5. R. C. Hart, R. J. Balla, G. C. Herring, “Non resonant referenced laser-induced thermal acoustics thermometry in air,” Appl. Opt. 38, 577–584 (1999).
    [CrossRef]
  6. S. L. Marple, Digital Spectral Analysis with Applications (Prentice-Hall, Englewood Cliffs, N.J., 1987).
  7. E. B. Cummings, “Laser-induced thermal acoustics,” Ph.D. dissertation (California Institute of Technology, Pasadena, Calif., 1995).
  8. A. H. Shapiro, The Dynamics and Thermodynamics of Compressible Fluid Flow (Wiley, New York, 1953), Vol. 2.
  9. H. W. Liepmann, A. Roshko, Elements of Gasdynamics (Wiley, New York, 1957).
  10. D. J. W. Walker, R. B. Williams, P. Ewart, “Thermal grating velocimetry,” Opt. Lett. 23, 1316–1318 (1998).
    [CrossRef]

1999 (2)

1998 (2)

A. Stampanoni-Panariello, B. Hemmerling, W. Hubschmid, “Temperature measurements in gases using laser-inducedelectrostrictive gratings,” Appl. Phys. B 67(1), 125–130 (1998).

D. J. W. Walker, R. B. Williams, P. Ewart, “Thermal grating velocimetry,” Opt. Lett. 23, 1316–1318 (1998).
[CrossRef]

1995 (1)

Balla, R. J.

Cummings, E. B.

Ewart, P.

Hart, R. C.

Hemmerling, B.

A. Stampanoni-Panariello, B. Hemmerling, W. Hubschmid, “Temperature measurements in gases using laser-inducedelectrostrictive gratings,” Appl. Phys. B 67(1), 125–130 (1998).

Herring, G. C.

Hornung, H. G.

Hubschmid, W.

A. Stampanoni-Panariello, B. Hemmerling, W. Hubschmid, “Temperature measurements in gases using laser-inducedelectrostrictive gratings,” Appl. Phys. B 67(1), 125–130 (1998).

Leyva, I. A.

Liepmann, H. W.

H. W. Liepmann, A. Roshko, Elements of Gasdynamics (Wiley, New York, 1957).

Marple, S. L.

S. L. Marple, Digital Spectral Analysis with Applications (Prentice-Hall, Englewood Cliffs, N.J., 1987).

Press, W. H.

W. H. Press, Numerical Recipes in C: the Art of Scientific Computing (Cambridge U. Press, New York, 1988).

Roshko, A.

H. W. Liepmann, A. Roshko, Elements of Gasdynamics (Wiley, New York, 1957).

Schlamp, S.

Shapiro, A. H.

A. H. Shapiro, The Dynamics and Thermodynamics of Compressible Fluid Flow (Wiley, New York, 1953), Vol. 2.

Stampanoni-Panariello, A.

A. Stampanoni-Panariello, B. Hemmerling, W. Hubschmid, “Temperature measurements in gases using laser-inducedelectrostrictive gratings,” Appl. Phys. B 67(1), 125–130 (1998).

Walker, D. J. W.

Williams, R. B.

Appl. Opt. (3)

Appl. Phys. B (1)

A. Stampanoni-Panariello, B. Hemmerling, W. Hubschmid, “Temperature measurements in gases using laser-inducedelectrostrictive gratings,” Appl. Phys. B 67(1), 125–130 (1998).

Opt. Lett. (1)

Other (5)

W. H. Press, Numerical Recipes in C: the Art of Scientific Computing (Cambridge U. Press, New York, 1988).

S. L. Marple, Digital Spectral Analysis with Applications (Prentice-Hall, Englewood Cliffs, N.J., 1987).

E. B. Cummings, “Laser-induced thermal acoustics,” Ph.D. dissertation (California Institute of Technology, Pasadena, Calif., 1995).

A. H. Shapiro, The Dynamics and Thermodynamics of Compressible Fluid Flow (Wiley, New York, 1953), Vol. 2.

H. W. Liepmann, A. Roshko, Elements of Gasdynamics (Wiley, New York, 1957).

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (5)

Fig. 1
Fig. 1

LITA signal from electrostrictive gratings in atmospheric air (32-shot average).

Fig. 2
Fig. 2

SNR versus E d 2 P 0 where E d is the driver-laser-pulse energy and P 0 is the interrogation beam power.

Fig. 3
Fig. 3

Percentage of shots with gas breakdown in the sample volume versus the driver-laser-pulse energy density.

Fig. 4
Fig. 4

Error and uncertainty of the speed of sound versus the SNR.

Fig. 5
Fig. 5

Error and uncertainty for the thermal diffusivity versus the SNR.

Equations (1)

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

Δcs=cs,meas-cs,calibcs,calib, ΔDT=DT,meas-DT,calibDT,calib

Metrics