Abstract

We describe the design and operation of a high speed optical tomography system for measuring two-dimensional images of a dynamic phase object at a rate of 5 kHz. Data from a set of eight Hartmann wavefront sensors is back-projected to produce phase images showing the details of the inner structure of a heated air flow. Series of animated reconstructions at different downstream locations illustrate the development of flow structure and the effect of acoustic flow forcing.

© Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |

  1. L. Hesselink, Optical Tomography, in Handbook of Flow Visualization, Wen-Jei Yang, ed. (Hemisphere, New York, 1989), Chap. 20.
  2. L. McMackin, B. Masson, N. Clark, K Bishop, R. Pierson and E. Chen, "Hartmann wavefront sensor studies of dynamic organized structure in flow fields," AIAA J. 33 (11), 2158-2164 (1995).
    [CrossRef]
  3. R. E. Pierson, E. Y. Chen, K. P Bishop, and L. McMackin, Modeling and measurement of optical turbulence by tomographic imaging of a heated air flow, Proc. SPIE 2827, 130-141 (1996).
    [CrossRef]
  4. D. J. Cha, S. S. Cha, Holographic interferometric tomography for ill-posed reconstruction from severely limited data, AIAA paper 95-2194.
  5. D. W. Watt, Fourier-Bessel expansions for tomographic reconstruction from phase and phase-gradient measurements: Theory and experiment, 1997 ASME Fluids Engineering Division Summer Meeting (American Society of Mechanical Engineers, New York, 1197), FEDSM97-3120.
  6. R. E. Pierson, E. Y. Chen, and L. McMackin, "Data recovery quality measured by a narrow band correlation metric," IEEE Trans. Image Process., submitted.
  7. P.G. Drazin, and W.H. Reid, Hydrodynamic Stability (Cambridge University Press, Cambridge, 1981), p.17.
  8. R. J. Hugo, L. McMackin, Non-intrusive linearized stability experiments on a heated axisymmetric jet, AIAA paper 97-1965.
  9. J. Sapayo and C. R. Truman, Study of the development of axismmetric and helical modes in heated air jets using optical tomography, AIAA paper 97-1809.
  10. S. Raghu, B. Lehman, and P. A. Monkewitz, On the mechanism of side jets generation in periodically excited axisymmetric jets, in Advances in Turbulence 3 (Springer Verlag, Berlin, 1990), p. 221-226.
  11. C. O. Paschereit, D. Oster, T. A. Long, H. E. Fiedler, and I. J. Wygnanski, Flow visualization of interactions among large coherent structures in an axisymmetric jet, Exp. Fluids. 12, 189-199 (1992).
    [CrossRef]
  12. L. McMackin, R. J. Hugo, K. P. Bishop, E. Y. Chen, R. E. Pierson, and C. R. Truman, High speed optical tomography system for quantitative measurement and visualization of dynamic features in a round jet, Exp. Fluids, submitted.
  13. R. J. Hugo and L. McMackin, Conditionally sampled two-dimensional optical wavefront measurements in the near-nozzle region of a heated axisymmetric jet, Proc. SPIE 2828, 50-61 (1996).
    [CrossRef]

Other (13)

L. Hesselink, Optical Tomography, in Handbook of Flow Visualization, Wen-Jei Yang, ed. (Hemisphere, New York, 1989), Chap. 20.

L. McMackin, B. Masson, N. Clark, K Bishop, R. Pierson and E. Chen, "Hartmann wavefront sensor studies of dynamic organized structure in flow fields," AIAA J. 33 (11), 2158-2164 (1995).
[CrossRef]

R. E. Pierson, E. Y. Chen, K. P Bishop, and L. McMackin, Modeling and measurement of optical turbulence by tomographic imaging of a heated air flow, Proc. SPIE 2827, 130-141 (1996).
[CrossRef]

D. J. Cha, S. S. Cha, Holographic interferometric tomography for ill-posed reconstruction from severely limited data, AIAA paper 95-2194.

D. W. Watt, Fourier-Bessel expansions for tomographic reconstruction from phase and phase-gradient measurements: Theory and experiment, 1997 ASME Fluids Engineering Division Summer Meeting (American Society of Mechanical Engineers, New York, 1197), FEDSM97-3120.

R. E. Pierson, E. Y. Chen, and L. McMackin, "Data recovery quality measured by a narrow band correlation metric," IEEE Trans. Image Process., submitted.

P.G. Drazin, and W.H. Reid, Hydrodynamic Stability (Cambridge University Press, Cambridge, 1981), p.17.

R. J. Hugo, L. McMackin, Non-intrusive linearized stability experiments on a heated axisymmetric jet, AIAA paper 97-1965.

J. Sapayo and C. R. Truman, Study of the development of axismmetric and helical modes in heated air jets using optical tomography, AIAA paper 97-1809.

S. Raghu, B. Lehman, and P. A. Monkewitz, On the mechanism of side jets generation in periodically excited axisymmetric jets, in Advances in Turbulence 3 (Springer Verlag, Berlin, 1990), p. 221-226.

C. O. Paschereit, D. Oster, T. A. Long, H. E. Fiedler, and I. J. Wygnanski, Flow visualization of interactions among large coherent structures in an axisymmetric jet, Exp. Fluids. 12, 189-199 (1992).
[CrossRef]

L. McMackin, R. J. Hugo, K. P. Bishop, E. Y. Chen, R. E. Pierson, and C. R. Truman, High speed optical tomography system for quantitative measurement and visualization of dynamic features in a round jet, Exp. Fluids, submitted.

R. J. Hugo and L. McMackin, Conditionally sampled two-dimensional optical wavefront measurements in the near-nozzle region of a heated axisymmetric jet, Proc. SPIE 2828, 50-61 (1996).
[CrossRef]

Supplementary Material (7)

» Media 1: MOV (351 KB)     
» Media 2: MOV (443 KB)     
» Media 3: MOV (427 KB)     
» Media 4: MOV (329 KB)     
» Media 5: MOV (441 KB)     
» Media 6: MOV (442 KB)     
» Media 7: MOV (379 KB)     

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 (6)

Fig. 1.
Fig. 1.

Schematic of the optical tomography apparatus made up of 8 diode laser illuminated Hartmann sensors. A tomographic back propagation algorithm creates a 2D flow image from 8 path integrated optical phase measurements.

Fig. 2.
Fig. 2.

Schematic of the tomography system model used to simulate performance.

Fig. 3.
Fig. 3.

Photographic flow visualization of shear layer vortex structures of interest.

Fig. 4.
Fig. 4.

Tomographic image sequences depicting the evolution of internal phase features of the heated round jet with downstream locations at two different forcing frequencies. [Media 1] [Media 2] [Media 3] [Media 4] [Media 5] [Media 6]

Fig. 5.
Fig. 5.

Animated tomographic sequence showing structure of a helical mode measured at 1.5D. [Media 7]

Fig. 6.
Fig. 6.

(a) 2-D time histories produced by stacking tomographic reconstructions and displaying them as an isotemperature surface. (b) cutaway showing internal features of the stack.

Equations (5)

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

n = 1 + 77.6 ( 1 + 7.52 × 10 3 λ 2 ) P T × 10 6
OPD i = beam path i [ n ( T ( x , y ) ) n ( T a ) ] dx dy
Δ ϕ i = δ i f L
Δ ϕ i = OPD i + 1 OPD i d
OPD i = d n = 0 i Δ ϕ n

Metrics