The use of a rotating disc to study the avalanching behaviour of a powder is discussed. It is shown that the strange attractor plotted in discreet time maps summarizes useful information on the rheological behaviour of powders and powder mixtures. In particular it is shown that the avalanching behaviour is related to the particle size distribution of the powder and that one can study the changes in rheological behaviour as another powder is mixed with it. The strange attractor patterns generated are dependent upon the environmental conditions under which the experiments are carried out. For this reason the measurements are referred to as an assessment of the holistic powder rheoiogy. The potential use of the disc to study the holistic rheology of powder systems is outlined.
Flow agents are widely used in industry, such as the plastics and pharmaceutical industry, to promote the flow of cohesive powders. Few studies of the quantitative effects of the flow agents on the flow of the powder have been reported. In this communication the effect of silica flow agents on the flow of a plastic powder is studied by means of avalanching behaviour. The avalanching behaviour of the powder as modified by the silica flow agents is summarized using descriptive parameters based on the calculation of fractal dimensions in data space and phase-space strange attractors. The structure of the strange attractors are shown to be statistically self-similar and effective descriptors of the change of rheology caused by the presence of the flow agents.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.