Digital image analysis techniques for the study of bubbling fluidized beds

Publisher Summary This chapter discusses the use of non-intrusive digital image analysis methods for the study of the behavior of bubbles and solid phases in two-dimensional beds. A bubbling fluidized bed is a two-phase gas–solid contacting device. According to the two-phase theory of fluidization, gas flow in excess of that required to maintain the dense phase at minimum fluidization (bubbling) conditions, flows through the bed in the form of gas pockets or bubbles. These bubbles exert the dominant influence on the mixing, heat/mass transfer, and reactant conversion capabilities of the fluidized bed. Such beds have been used very often in the past to obtain qualitative and quantitative information on bubble characteristics. However, photographic techniques employed to extract quantitative information on bubbles are laborious and require subjective interpretation in the delineation of bubble–solid phase boundaries. The labor-intensive effort reduces the motivation for obtaining sufficient data for making reasonable statistical inferences. Two-dimensional beds have also been used to study the influence of bubble motion on the motion of solids in the bed.

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