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把鼓泡流化床看成是一个与环境有能质交换和能量耗散的热力学系统，用非平衡态热力学和耗散结构理论研究了流化床由均匀到不均匀流化状态的过渡。根据流化床的质量、动量、能量方程和Ｇｉｂｂｓ公式得出了系统的熵平衡方程和熵产生方程，基于Ｐｒｉｇｏｇｉｎｅ的耗散结构理论建立了鼓泡流化床的过渡态判据，提出了临界鼓泡速度计算方法。应用该判据对流化床中产生气泡的几个主要影响因素进行了分析，临界鼓泡速度与临界流化速度之比与颗粒直径的立方和气－固密度差成反比，与流体粘度的平方成正比，计算表明理论结果与有关文献的实验值吻合较好
The bubbling fluidized bed is considered as a thermodynamic system with energy exchange and energy dissipation. The non-equilibrium thermodynamic and dissipative structure theory is applied to study the fluidized bed transition from homogeneous to non-uniform fluidized state. According to the mass, momentum, energy equation and Gibbs formula of the fluidized bed, the entropy equation and entropy equation of the system are obtained. Based on the theory of dissipative structure of Prigogine, the transition state criterion of bubbling fluidized bed is established and the critical Bubble rate calculation method. This criterion is used to analyze several major influencing factors of bubble generation in fluidized bed. The ratio of critical bubbling velocity to critical fluidizing velocity is inversely proportional to cubic and gas-solid density difference of particle diameter, and the square of fluid viscosity Is proportional to the calculated results show that the theoretical results and the experimental data of the literature is in good agreement