The expansion behavior of solid particles fluidized by liquid within fixed packings was studied by the conductimetric method. The electrodes conforming the conductivity cell were embedded in the container walls with their center at half the height of the fluidized bed. The axial solids distribution was also measured by this technique by placing ten conductivity cells along the column. The study is limited to intermediate and turbulent flow regimes, due to the density and size of the particles used. Depending on the geometry of the packed bed, the operating range in terms of superficial velocity and the homogeneity of the fluidized bed differ from those obtained for fluidization in an empty column. Taking into account geometric aspects of the systems, a method of estimating the fluidization parameters is derived.