Solids suspension cloud height

K.J. Bitterof and S.M. Kresta, Prediction of cloud height for solids suspension in stirred tanks, CHISA Proceedings, Prague, August 2002. 

In solid suspensions, there is a distinct level to which most of the solids are lifted within the fluid even at speeds above Njs- The distance from the bottom of the vessel to this level is called the cloud height (//doud)-The liquid below this height is solid rich, while above it there is only an occasional visit by a few small solids. 

Hcioud Cloud height, i.e., distance from bottom of vessel to height where most of the solids are lifted in solid-suspensions (m) Mass transfer coefficient (m/sec) ksL Mass transfer coefficient for a single... 

Hicks, M.T. Myers, K.J. Bakker, A. Cloud 38. height in solids suspension agitation. Chem. 

Another representation of solid suspension is through the cloud height (Kraume 1992 Hicks et al. 1997 Bujalski et al. 1999 Bittorf and Kresta 2003 Takenaka et al. 

Bittorf KJ, Kresta SM. (2003) Prediction of cloud height for solid suspensions in stirred tanks. Trans IChemE., 81(Part A) 568-577. 

In solid suspensions there is a distinct level to which most of the solids are lifted within the fluid even at speeds above Njs. The distance from the bottom of the vessel to this level is called the cloud height. The liquid below this height is solid-rich, while above it there is only an occasional visit by a few small solids. Hicks et al. (1993, 1997) and Bnjalski et al. (1999) have reported extensive data on cloud height and solid distribution. Bnjalski et al. (1999) also reported that the blending between the solid-rich and soUd-ftee portions is rather poor, and can result in a blend time as much as 20 times longer in the solid-free region than in the solid-rich volume. 

Hicks M. T., et al. (1993). Cloud height, fillet volume, and the effect of multiple impellers in solid suspension, presented at Mixing XIV, Santa Barbara, CA, June 20-25. 

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