Digital Image Analysis Technique for mixing pattern measurements in bi-dispersed 2D gas fluidized beds

This work concerns a new experimental technique based on Digital Image Analysis aimed at the measurement of the mixing behaviour of the granular phase in a 2D fluidized bed. In particular, the preliminary results obtained about the mixing pattern of a bi-disperse 2D gas fluidized bed are reported. Two different kind of particles were fluidized having the same density but different size. The technique is based on suitable colour-field decomposition of the fluidized bed, in which particles of different colours are employed. The technique here proposed can effectively measure the concentration field in the whole bed during operation, thus obtaining data that can be reliably used for CFD simulation validation. Moreover, it is possible to follow the mixing and segregation dynamics of powders in the fluidized bed. Notably, the technique here developed can be used for both gas-solid or liquid-solid fluidized beds.