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Abstract

Scattering theory predictions of the changes in the attenuation of sound at frequencies between 100 Hz and 100 kHz due to changes in the (spherical) particle size distributions in airborne particulate suspensions with characteristics typical of pulverized fuel flows are considered. These predictions are compared with a criterion for the detectability of insertion loss changes, assuming a sensor separation of 100 mm. It is concluded that, for such a separation, at frequencies greater than 30 kHz and concentrations greater than 0.5 kg/kg, it is feasible to monitor changes in the fraction of particles with radii above 37.5 μm by measuring cross-pipe sound attenuation.

Keywords

acoustic suspension particle size distributions

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Predicted influences of changes in particle size distribution in pulverized coal on attenuation of sound

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