Abstract

A technique has been developed for determining the Sauter mean droplet diameter in a nozzle spray by direct analysis of the small angle, forward scattered light profile. The spatial intensity of the profile was scanned with a microphotometer and the information recorded on punched paper tape for later reduction by computer. A knowledge of a particular functional form for the intensity profile was required for computer processing of the data, and it was therefore determined empirically that the natural log of the intensity of the small angle, forward scattered light had a gaussian profile with respect to the scattering half-angle.

© 1970 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |

  1. R. A. Dobbins, Princeton University, Rep. AF18 (600)-1527. See also R. A. Dobbins, L. Crocco, I. Glassman, J. AIAA 1, 1882 (1963).
    [CrossRef]
  2. N. Cohen, M. Webb, Princeton University, Rep. AF49-(638)-938. See also J. H. Roberts, M. J. Webb, J. AIAA 2, 583 (1964).
    [CrossRef]
  3. W. E. Deiss, M.S. thesis, Princeton University, Princeton, N. J. (1970).
  4. Presented at Session 26 of ASME, Cleveland, Ohio, 12 March 1969.
  5. “The Design and Performance Analysis of Gas-Turbine Combustion Chambers,” Northern Research and Engineering Corp. Rep. No. 1082, 1964.

Cohen, N.

N. Cohen, M. Webb, Princeton University, Rep. AF49-(638)-938. See also J. H. Roberts, M. J. Webb, J. AIAA 2, 583 (1964).
[CrossRef]

Deiss, W. E.

W. E. Deiss, M.S. thesis, Princeton University, Princeton, N. J. (1970).

Dobbins, R. A.

R. A. Dobbins, Princeton University, Rep. AF18 (600)-1527. See also R. A. Dobbins, L. Crocco, I. Glassman, J. AIAA 1, 1882 (1963).
[CrossRef]

Webb, M.

N. Cohen, M. Webb, Princeton University, Rep. AF49-(638)-938. See also J. H. Roberts, M. J. Webb, J. AIAA 2, 583 (1964).
[CrossRef]

Other (5)

R. A. Dobbins, Princeton University, Rep. AF18 (600)-1527. See also R. A. Dobbins, L. Crocco, I. Glassman, J. AIAA 1, 1882 (1963).
[CrossRef]

N. Cohen, M. Webb, Princeton University, Rep. AF49-(638)-938. See also J. H. Roberts, M. J. Webb, J. AIAA 2, 583 (1964).
[CrossRef]

W. E. Deiss, M.S. thesis, Princeton University, Princeton, N. J. (1970).

Presented at Session 26 of ASME, Cleveland, Ohio, 12 March 1969.

“The Design and Performance Analysis of Gas-Turbine Combustion Chambers,” Northern Research and Engineering Corp. Rep. No. 1082, 1964.

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 (10)

Fig. 1
Fig. 1

The apparatus for determining the Sauter mean-droplet diameter of an aerosol by measuring the intensity profile of the small angle, forward scattered light.

Fig. 2
Fig. 2

An illustration of the pressure chamber modifications used to prevent droplet accumulation on the windows and to reduce the density of the spray being analyzed.

Fig. 3
Fig. 3

A typical plot of the baseline light intensity profile proving the validity of the straight line curve fit.

Fig. 4
Fig. 4

A typical plot of the fitted scattered light intensity profile (due to droplets’ presence in light beam) proving the validity of the loge-gaussian curve fit.

Fig. 5
Fig. 5

The Sauter mean-droplet diameters for several identical nozzles.

Fig. 6
Fig. 6

The comparison of the Sauter mean-droplet diameter obtained with and without flow splitting slot is shown, proving that the presence of the slot does not change the SMD obtained. These data are then compared with the Sauter mean-droplet diameter obtained without slot seventeen days earlier, proving the system consistent from day to day.

Fig. 7
Fig. 7

Sauter mean-droplet diameter vs fuel flow ~85°/3.5 × 104 kg/m2 nozzle.

Fig. 8
Fig. 8

Sauter mean-droplet diameter vs fuel flow ~85°/8.43 × 104 kg/m2 nozzle.

Fig. 9
Fig. 9

Sauter mean-droplet diameter vs fuel flow ~85°/2.46 × 105 kg/m2 nozzle.

Fig. 10
Fig. 10

Sauter mean-droplet diameter vs fuel flow ~85°/1.68 × 106 kg/m2 psid nozzle.

Equations (13)

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

N r ( D ) = C exp δ 2 { [ ( log e ( α D / D D ) ] } 2 D 4 ( D D ) ,
I ( θ ) = 0 [ 2 J 1 ( Δ ) Δ ] 2 N r ( D ) D 4 d D / 0 N r ( D ) D 4 d D ,
I ( θ ) = 0 D / D ¯ [ 2 J 1 ( Δ D / D ¯ ) ( Δ D / D ¯ ) ] 2 1 1 ( D ¯ / D ) ( D / D ¯ ) × exp { δ 2 [ log e a ( D / D ¯ ) ( D / D ¯ ) ( D / D ¯ ) ] 2 } d ( D D ¯ ) / 0 D / D ¯ × 1 [ 1 ( D ¯ / D ) ( D / D ¯ ) ] exp { δ 2 [ log e a D / D ¯ ( D / D ¯ ) ( D / D ¯ ) ] 2 } × d ( D D ¯ ) .
θ ˜ i = log 10 ( θ i ) , I ˜ i = log 10 ( I i ) .
S ˜ i = I ˜ ¯ i m + b , T ˜ i = ( θ ˜ ¯ b ) / m ,
I ˜ ¯ i = log 10 ( I ¯ i ) , θ ˜ i = log 10 ( θ ¯ i ) ,
S ˆ i = 10 S ˜ i , T ˆ i = 10 T ˜ i ,
Y ¯ i = log e ( I ¯ i + 1 )
Y ˆ = a { exp [ 1 2 ( θ / σ ) 2 ] } = a { exp [ ( 1 2 ) θ 2 β ] } ,
Y ˆ ( 0 ) = a . I ˆ ( 0 ) = e a 1.
d i = ( 1 / 5.3 × 10 5 ) α i λ / Π x i ,
X i = σ ( 2.0 log e { log e [ P i ( e a 1 ) + 1 ] / a } ) 1 2
P i = 0.1,0.2,0.3 for i = 1,2,3.

Metrics