Application of the Hausner ratio to fluidised powder systems

5 Application of the Hausner ratio to fluidised powder systems 

Geldart et al. (1984) in an extension of the work on the classification of fluidisable powders used the ratio of tapped density to a loosely packed density (Hausner ratio) to predict the type of particle movement that can occur with powders having various degrees of cohesiveness. Re-appraisal of this work shows that with a Hausner ratio below 1.27 (Table 1.8), all the powders investigated could be classified as aeratable. Powders with a Hausner ratio above 

5 were, however, cohesive and difficult to fluidise. There was also an intermediate group between the Hausner ratios of 1.3 and 1.5 which showed intermediate fluidisable properties and behaviour. 

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