论文标题:气固流化床中空隙率及颗粒碰撞压力的非线性分析
Nonlinear Analysis of Voidage and Particle Colliding force in Gas-Solid Fluidized Bed
论文作者 杨虎
论文导师 石炎福,论文学位 硕士,论文专业 化学工程
论文单位 四川大学,点击次数 95,论文页数 97页File Size2542k
2001-02-01论文网 http://www.lw23.com/lunwen_148539642/ 气固流化床;空隙率;颗粒碰撞压力;时间序列;功率谱;混饨
Gas-Solid Fhtidized Bed; Voidage; Particle Colliding Force; Time Series; Power Spectrum; Chaos
空隙率和颗粒碰撞压力都是气固流化床设计和操作中的主要参数。本文采用不同的分析方法分析、研究了气固流化床中不同操作条件下的空隙率时间序列和颗粒碰撞压力时间序列。 在完全流态化状态，本文采用PV4A型颗粒速度仪测定了具有不同粒径的PVC和沙在不同气速和不同空间位置上的空隙率时间序列，并采用膜式压力传感器和SYDC-Ⅱ型多通道数据采集仪测定了相应条件下的颗粒碰撞压力时间序列。 采用统计分析、功率谱分析研究了气固流化床中空隙率和颗粒碰撞压力随操作条件的变化。主要研究了空隙率和颗粒碰撞压力随操作气速、轴向距离、径向距离、颗粒种类等的变化，同时研究了空隙率动态信号和颗粒碰撞压力动态信号的主频范围、能量值等随操作条件的变化。通过分析得出空隙率动态信号和颗粒碰撞压力动态信号可能是混沌的。 基于相空间重构理论，从单变量时间序列提取混沌特征参数(关联维、最大Lyapunov指数、Kolmogorov熵)来定量刻划流化床动力学系统的吸引子，定量地说明运动系统的复杂程度。本文重点分析了混沌特征参数(关联维、最大Lyapunov指数、Kolmogorov熵)随操作气速、轴向距离、径向距离、颗粒直径、颗粒密度等的变化及原因。 各种分析方法的结果显示了基本相同的特征，为流化床的工业设计、放大和操作控制提供了依据，具有重要的工业应用价值和指导意义。
Both of voidage and particle colliding force are key parameters in gas-solid fluidized beds. The time series of voidage and particle colliding force at different operation conditions is analyzed and researched by statistic method-. power spectrum and chaos theory in this papers. For PVC sands with different diameter, the time series of voidage is measured by PV4A particle velocity analysis at different operation conditions, and a multchannel data automatic acquisition and pressure strain gauge are used at different operation conditions to acquire the time series of particle colliding force in the experiment. To understand the variation of voidage and particle colliding force vs operation conditions, the statistic method and power spectrum are used. The variation of voidage and particle colliding force vs operation gas velocity axial and radial positio~ and particle type is mainly discussed. On the other hand, it is researched that the range of main frequency and the power at different frequency of the signals of voidage and particle colliding force vary with operation conditions. The results show that the singles of voidage and particle colliding force is probably chaotic. Based on the theory of phase space reconstructing, the chaos characteristic parameters, such as correlate dimension Lyapunov exponent and Kolmogorov entropy, which are drawn out from the time series of voidage and particle colliding force quantitatively describe the complexity of the gas-solid fluidized bed kinetic system and the strange attractor in gas-solid fluidized beds. The variation of chaos characteristic parameters vs operation gas velocity-, axial and radial positionsparticle type and diameter is mainly analyzed. The result drawn from the signals by different analysis give almost the same characteristics. This offers foundations of industrial application~. design-. scale-up and control of gas-solid fluidized bed and has important value and instruct meaning.
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