Longitudinal Acoustical Resonance Measurement of Particle Loading and Sizing in Gas-Solids Flow

该项目中的声学共振测量技术为气相流态化颗粒的质量负荷和尺寸提供了一种非侵入性的实时测量。气体中颗粒的两相混合物中的声速随着颗粒质量密度的增加而减小。通过测量与声速线性相关的共振频率的降低，可以确定粒子的质量密度。由于声速与频率的相关性是弥散的，声速提供了一种通过测量不同共振模式的频率来确定颗粒大小的方法。在实际应用中，声学共振测量需要纵向共振。对这种应用于纵向共振的非侵入性技术进行了一阶声学分析，用于电力发电厂煤粉气力输送的条件。分析调查包括对工厂的全部运行范围进行评估。为验证该技术，在闭环系统、实验室试验台和某电厂进行了实验测量。这些分析用来解释实验测量的结果。

The acoustical resonance measurement techniques in this project provide a nonintrusive and realtime measurement of mass loading and sizing of particles fluidized by a gas phase. The speed of sound in a two-phase mixture of particles in gas decreases as the mass density of the particles increases. By measuring the decrease in the resonant frequencies, which are linearly related to the speed of sound, the mass density of the particles is determined. Because the speed of sound is dispersive with the frequency dependence of the sound speed provides a method of determining the particle sizing by measurement of the frequencies of different resonant modes. For realistic applications, a longitudinal resonance is required for the acoustical resonance measurement. A first order acoustical analysis of this nonintrusive technique applied to longitudinal resonances is used for the conditions found in the pneumatic conveyance of pulverized coal in electrical utility power plants. The analytical investigation includes evaluation over the full operating ranges of the plant. Experimental measurements on a closed loop tests laboratory scale test stand and at a power plant are conducted to verify the technique. The analyses are used to interpret the results of the experimental measurements.