(95v) Stability Analysis of Uniform Gas Solids Flow

Uniform distribution of gas solids flow should be ensured to gain sufficient performance of fluidized beds. The highly chaotic entropy dissipation across solids bed will trigger non-uniform fluidization, although distributor plays an important role in obtaining homogenous gas stream. Hence, total solids pressure loading (Φ_T), the pressure drop ratio between solids bed and distributor, is introduced here to present their interaction. The boundary between uniform and non-uniform fluidization can be detected by stability analysis based on Prigogine’s minimum of entropy production principle, and this criterion for N parallel paths can be simplified into calculating the second derivative of pressure drop through one path with respect of Φ_T. Furthermore, a phase diagram, illustrating the effects from operational parameter (Φ_T), geometrical characteristics of distributor (C_d) and property of solids (Ga) on instability of uniformity, is attained to draw some useful conclusions of robust uniform fluidization.