ASSESSMENT OF ACOUSTIC WAVES ATTENUATION IN THE DUSTED FLOWS IN THE BOILERS OF THERMAL POWER PLANTS
The analysis of the physical mechanisms of attenuation of acoustic waves in the dusted gas stream is presented. The comparative assessment of the impact of various possible mechanisms of attenuation of acoustic waves on the effectiveness of sound cleaning of dusted surfaces of equipment placed in the ducts of thermal power plants was made. Wave attenuation coefficients were calculated, in the flow of flue gases, and at vicinity of solid surfaces in the wide frequency band of acoustic waves. Attenuation of waves in a dustad gas flow at relatively low frequencies is significantly higher than attenuation of acoustic waves in the clean gas. Calculations confirmed presence of anomalous attenuation of acoustic waves by the dust particles suspended in a gas flow in a range of sizes PM10 (< 10 ìm). Calculations were performed to account polydispersity of dust particles, based on of the actual distribution of fly ash particle size distribution downstream the boiler of coal-fired thermal power plants. Numerical evaluation was performed, on the changes of the sound pressure of acoustic waves in the infrasonic range in a dusted gas stream. Bibl. 33, Fig. 4.
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