Local phase holdups in an inverse three-phase turbulent bed of 150 mm i.d. and 4350 mm height were measured simultaneously by micro-electrical conductivity probe technique in this study.The experiments were carried out with polyethylene particles （dp=4.01 mm, ρs=926 kg·m -3）,air, and water[0.05%（mass）SCMC, 0.20%（mass）SCMC] as solid phase,gas phase and liquid phase respectively.540 sets of experimental data of local phase holdups in radial direction were obtained under Ug=U g3. It was found that the distribution of local solid holdup showed a maximum peak at r/R=（0.75—0.90）. The range of maximum peaks was larger than that of conventional fluidized beds. The distribution of local gas holdup in radial direction showed a maximum value at the column center and a minimum value near the wall.Moreover,the non-homogeneous distribution of local gas holdup in radial directions was more evident than that of conventional fluidized beds.The different operation regimes as well as the corresponding three specific gas velocities （U g1 ,U g2 and U g3） were obtained on the basis of the axial distribution characteristics of cross-sectional average solid holdups.The effect of the operating conditions （liquid viscosity, initial volume fraction of solids H s0/H0, initial liquid height H l0 ） on the specific gas velocities was presented.
The local chaos characteristics of the time series pressure fluctuations of gas liquid two phase flow in a self aspirated reversed flow jet loop reactor are studied by the deterministic chaos analysis technique. It is found that the estimated local largest Lyapunov exponent is positive in all cases and the profile is similar to that of the local fractal dimension in this reactor. The positive largest Lyapunov exponent shows that the reactor is a nonlinear chaotic system. The obvious distribution indicates that the local nonlinear characteristic parameters such as the Lyapunov exponent and the fractal dimension could be applied to further study the flow characteristics such as the flow regine transitions and flow structures of the multi phase reactors.
