“…Such work has been reported, for example, in Wu, Orta, and Kantzas (2011) in which a modified medical CT scanner was used to study flow regimes in a fluidized bed. Similar works for studying structured packings have been reported in Janzen et al (2013) and Toye, Crine, and Marchot (2005). In Grudzien, Niedostatkiewicz, Adrien, Tejchman, and Maire (2011), an X-ray CT system was used to investigate granular flows in silos.…”