Rheological Study of Loosened Bulk Granular Materials

Loosened bulk materials occur, for example, during grinding in a tube mill. Thus, a rheological study of bulk granular materials which are loosened by fluidisation should lead to a better characterization of the flow and conveying properties of the material when ground in the mill. For this measurement of fluidised bulk materials an agitating device and a rotary viscosimeter have been developed, designed and tested. First results are presented and discussed showing the fluidisation behaviour and density of the bulk material as a function of grain size as well as the flow properties as a function of the grain size and degree of fluidisation. Finally, a projection of further research work is given.