Based on the coupled-phase model describing the propagation of ultrasonic waves in two-phase medium

considering the particle size distribution

particle scattering and interaction between particles

the model was modified. The modified model of the gas-solid two-phase in the power plant boiler primary air pipeline was established. The relationship between the acoustic attenuation coefficient and the sound speed prediction in primary air pipeline was obtained by considering the ultrasonic frequency

particle concentration

two-phase density and particle size distribution. The results show that

for the general primary air pipeline

an increase in the ultrasonic frequency or the particle size or the particle concentration will result in an increase in attenuation

and an increase in the density of the air will result in a decrease in attenuation. When the above parameters change

the dominance of various attenuation mechanisms affecting ultrasonic attenuation also changes. For the particle volume concentration within 0.05%

the sound speed decreases linearly with increasing of the particle concentration.