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arXiv · 1408.3261

The yielding of concentrated cohesive suspensions can be deformation rate dependent

Richard Buscall·Peter J. Scales·Anthony D. Stickland·Hui-En Teo·Tiara E. Kusuma·Sayuri Rubasingha·Daniel R. Lester
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Abstract

The yielding of concentrated cohesive suspensions can be deformation-rate dependent. One consquence of this is that a single suspension can present in one several different ways, depending upon how it is tested, or more generally, how it is caused to flow. We have seen variously Herschel-Bulkley flow, highly non-monotonic flow curves and highly erratic or chaotic yield, all in one suspension. In controlled-rate testing one sees a systematic effect of deformation rate. In controlled stress testing, matters are more subtle. Whereas step-stress creep testing will elicit reproducible behaviour, any attempt to determine a flow curve by, e.g. stepping up or sweeping stress at an inappropriate rate can lead to highly irreproducible behaviour.

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Richard Buscall, Peter J. Scales, Anthony D. Stickland, Hui-En Teo, Tiara E. Kusuma, Sayuri Rubasingha, Daniel R. Lester. 2014-08-14. The yielding of concentrated cohesive suspensions can be deformation rate dependent. https://arxiv.org/abs/1408.3261

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