3. Experimental results
The two types of particles were fluidized in the 2D fluidized bed
with different fixed heights and thicknesses. Bed heights of 0.1, 0.2
and 0.3 m, were employed to obtain bed aspect ratios of h/w=0.2, 0.4
and 0.6, respectively. Moreover, bed thicknesses of 0.5, 1.0 and 2.0 cm
were evaluated, and the same fluidization–defluidization process was
employed during each of the experiments. Namely, the bed was
fluidized at a superficial gas velocity that was 1.2−1.5 times greater
than the minimum fluidization velocity, and the gas flow was
progressively reduced until U=0. The bed was maintained under
these conditions for 20 min. Next, the gas flow was progressively