Measurements of porosity of a gas-solid fluidized bed

Two original methods of measurements of the vertical profile of porosity in a column with a gas-solid fluidized bed, i.e. a capacitive method and an optical-pressure method, are presented in this paper. The essence of operation of each method, the results of initial measurements and comparison with results quoted in the literature have been described. Some advantages and drawbacks of these methods have also been estimated.