An Experimental study of the electro-fluidized bed (EFB) has been carried out to demonstrate the effect of an imposed dc field on bed dynamics. The three types of EFB were used. Type 1: bed with the flow perpendicular to the uniform field, Type 2: parallel to the uniform field, and Type 3: perpendicular to the non-uniform field.
The general tendency of Type 3 was similar to Type 1 in spite of non-uniformity of the field, while Type 2 behaved quite differently. The distinctive phenomenon in Type 1 and 3 is that: in zero humidity, bed particles attached to the electrodes and eventually formed a freezing zone near the electrodes; as humidity increased, however, the freezing zone extended over the whole bed and fluidization ceased completely. On the other hand, channeling was more pronounced in Type 2.
An approximate field analysis was made to explain these bed behaviors. It was found that the space charge generated in the bed markedly influenced the bed dynamics.
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