【摘要】 流化床中的气固两相流动是一个高度复杂的非线性混沌系统。本文利用激光粒子动态分析仪（ＰＤＡ）得到的循环流化床中颗粒脉动速度信号，采用ＦＦＴ分析了脉动信号的宽频谱特征，在此基础上应用小波法分析了脉动信号的动态特征，得到了颗粒脉动速度的微观结构，指出颗粒脉动速度的非线性特性是流化床具有混沌特性的根源，且在不同的尺度上颗粒脉动速度表现出各向异性的特征。更多还原

【Abstract】 For observing the complex gas solid two phase flow in a fluidized bed reactor, a particle dynamic analyser (PDA) is employed to record the instantaneous velocity of the particles in a circulating fluidized bed (CFB). The broadband frequency spectrum of the particle velocity is obtained by FFT, and by using wavelet transform, the dynamic characteristics of the velocity fluctuation and also the fine structure of the velocity fluctuation and also the fine structure of the velocity fluctuation are analyzed. Some conclusions are drawn.更多还原