Abstracts

Topic: Y. Sivathanu, J. Lim, L. E. Reinhart, and R. C. Bowman, (2007),

“Structure of Plumes from Burning Aluminized Propellant Estimated using Fan Beam Emission Tomography,”

AIAA Journal, vol. 45, No. 9, pp. 2259-2266.

Fan beam emission tomography in the 1-5-µm band is used to estimate the structure of a solid rocket propellant plume. Fan beam emission tomography consists of two components. The first is a pair of orthogonal high-speed imaging spectrometers and scanners that measures the spectral radiation intensities from 1.3 to 4.8 µm at 256 view angles. The second is a robust deconvolution algorithm that estimates the structure of the plume from the spectral radiation intensity measurements. The deconvolution algorithm is based on the maximum likelihood estimation method in conjunction with a linearized radiative transfer equation. The radiation intensity measurements were completed in a series of burns using 2.5-cm-diam by 1.25-cm-long strands of aluminized solid rocket composite propellant. In general, the aluminum diffusion-flame particulate temperatures in the plume are much higher than the gas temperatures. The gaseous combustion product concentrations are much lower in the middle of the plume than at the outer edges. This indicates a diffusion-flame-type structure for the plume, caused by the fact that the composite solid rocket propellant is fuel-rich. The results indicate that reliable plume-structure measurements can be obtained using fan beam emission tomography.