激光波长调制检测循环湍动流化床局部颗粒浓度

Determination of Local Particle Concentration in Turbulent Fluidized Bed by Laser Wavelength Modulation

针对当前方法致检测的准确度低,检测过程复杂等问题,提出一种利用激光波长调制实现循环湍动流化床局部颗粒浓度检测的方法。首先根据颗粒动力学理论模拟颗粒脉动流动和k-ε双方程模型实现气固湍流流动模拟,建立循环湍动流化床气固两相流动的数学模型,实现循环湍动流化床气固两相流动特性的分析,然后通过改变激光二极管驱动电流时输出的波长扫描循环湍动流化床局部颗粒浓度的峰值,并利用锁相放大的方法,对通过的循环湍动流化床局部颗粒浓度进行检测,提高检测的准确度。实验结果表明,本文方法能够准确描述循环湍动流化床气固两相流动特性,检测准确度高。

in order to solve the problems of low accuracy and complex detection process, a method for detecting the local particle concentration in a circulating turbulent fluidized bed using laser wavelength modulation is proposed. According to the kinetic theory of granular particle simulation of pulsating flow and realize double equation model of gas -solid turbulent flow simulation, the establishment of circular turbulent fluidized bed gas-solid two-phase flow mathe- matical model, analysis of circulating turbulent gas-solid two-phase flow characteristics, then by changing the laser diode drive current when the output wavelength scanning cycle of local turbulent fluidized bed the particle concentration peak, and using the method of phase locking amplifier, to cycle through the turbulent fluidized bed local particle con- centration detection, improve the detection accuracy. The experimental results show that the method can accurately de- scribe the gas-solid two-phase flow characteristics in the circulating turbulent fluidized bed, and the detection accura- cy is high.