Traveling column for comparison of invasive and non-invasive fluidization voidage measurement techniques

Investigation of particle velocity in FCC gas-fluidized beds based on different measurement techniques

“…However, except for our recent voidage data (Dubrawski et al, 2013), the accuracy of many of these techniques has not been verified by comparing results obtained by alternative techniques under identical operating conditions. This makes it difficult to investigate the merits and reliability of each measurement technique.…”

“…In the present study we extended the reporting of results from the novel traveling fluidized bed (TFB), designed and built to provide identical operation in different physical settings and allowing direct comparison of alternate experimental measurement techniques (Dubrawski et al, 2013). Operating with the same equipment, with the same particles and under the same experimental conditions eliminates differences due to discrepancies between equipment, particles and operating conditions as sources of variation in data.…”

Fast X-ray tomography for the quantification of the bubbling-, turbulent- and fast fluidization-flow regimes and void structures

“…Figure 13 shows the measured void parameters: Void volume (a), void length (b) and the cylindrical diameter (c) if the assumption is made voids are cylinder shapes, Figure 13 (d) confirms this assumption is a reasonable one, the figure shows the void volume is directly proportional to void length. Theory suggests that U c is the point at which the largest stable bubbles exist, after U c bubbles breakup in smaller transient voids [20]. A decrease in void volume, as well as length is seen to occur at U c , after which both continue to increase.…”

Triple Phase Simulation of Bubbling Fluidized Beds of Geldart “A” Particles with a Bubble-Based Drag Model

“…Two benchmark cases, namely the experimental measurements presented by Dubrawski et al [9] and Zhu et al [10], are considered. For the case of Dubrawski (case A, Figure 3(a)), the lower section bed is 0.96 m high and 0.133 m of diameter, and the upper section is 0.59 m high and 0.19 m of diameter, Dubrawski using different advanced experimental techniques in the "Traveling fluidized bed" to determine local voidage, bed expansion and so on.…”