As shown in Fig. 5 a group of experimental data sets (represented
by filled symbols) were not in agreement with the experimental
results of the present study (represented with circles) and those of
previous investigations (represented by empty symbols and a cross).
Some of the deviations in the experimental results were unexpected.
For instance, in the results obtained by Rowe and Everett [23], which
are represented by filled squares and corresponded to fluidized
particles with a dp of 210 μm and beds with a thickness of 1.4, 2.6, 5.0
and 10.2cm , respectively, deviations were not observed until the bed
thickness reached 14.3cm At this point, which is represented by an
empty square, wall effects did not influence the minimum fluidization
velocity. An explanation for these discrepancies will be discussed in
the following section